essay questions on photosynthesis

Critical Thinking Questions

• ATP and NADPH are forms of chemical energy produced from the light dependent reactions to be used in the light independent reactions that produce sugars.
• ATP and NADPH are forms of chemical energy produced from the light independent reactions, to be used in the light dependent reactions that produce sugars.
• ATP and NADPH are forms of chemical energy produced from the light dependent reactions to be used in the light independent reactions that produce proteins.
• ATP and NADPH are forms of chemical energy produced from the light dependent reactions to be used in the light independent reactions that use sugars as reactants.
• NADPH and ATP molecules are produced during the light-independent reactions and are used to power the light-dependent reactions.
• Sugar and ATP are produced during the light-dependent reactions and are used to power the light-independent reactions.
• Carbon dioxide and NADPH are produced during the light-independent reactions and are used to power the light-dependent reactions.
• NADPH and ATP molecules are produced during the light-dependent reactions and are used to power the light-independent reactions.

Examine the illustration of the photosynthesis equation. How does the equation relate to both photosynthesis and cellular respiration, and what is the connection between the two processes?

• Photosynthesis utilizes energy to build carbohydrates, while cellular respiration metabolizes carbohydrates.
• Photosynthesis utilizes energy to metabolize carbohydrates, while cellular respiration builds carbohydrates.
• Photosynthesis and cellular respiration both utilize carbon dioxide and water to produce carbohydrates.
• Photosynthesis and cellular respiration both metabolize carbohydrates to produce carbon dioxide and water.
• When photons strike photosystem (PS) I, pigments pass the light energy to chlorophyll, molecules that excite electrons, which are then passed to the electron transport chain. The cytochrome complex then transfers protons across the thylakoid membrane and transfers electrons from PS-II to PS-I. The products of the light-dependent reaction are used to power the Calvin cycle to produce glucose.
• When photons strike photosystem (PS) II, pigments pass the light energy to chlorophyll a molecules that in turn excite electrons, which are then passed to the electron transport chain. The cytochrome complex transfers protons across the thylakoid membrane and transfers electrons from PS-I to PS-II. The products of the light-dependent reaction are used to power the Calvin cycle to produce glucose.
• When photons strike photosystem (PS) II, pigments pass the light energy to chlorophyll a molecules that excite electrons, which are then passed to the electron transport chain. The cytochrome complex transfers protons across the thylakoid membrane and transfers electrons from PS-II to PS-I. The products of the light-dependent reaction are used to power the Calvin cycle to produce glucose.
• When photons strike photosystem (PS) II, pigments pass the light energy to chlorophyll a molecules that excite electrons, which are then passed to the electron transport chain. The cytochrome complex transfers protons across the thylakoid membrane and transfers electrons from PS II to PS I. The products of the light-independent reaction are used to power the Calvin cycle to produce glucose.
• Because UV rays and X-rays are high-energy waves, they penetrate the tissues and thus damage cells.
• Because UV rays and X-rays are long-wavelength waves, they penetrate the tissues and thus damage cells.
• Because UV rays and X-rays are low-energy waves, they cannot penetrate tissues and thus damage cells.
• Because UV rays and X-rays are low-frequency waves, they can penetrate tissues and thus damage cells.
• Photosynthesis is not possible.
• Photosynthesis is possible.
• Photosynthesis is possible only with blue light.
• Photosynthesis is possible only with green light.
• After splitting water in PS-I, high-energy electrons are delivered through the chloroplast electron transport chain to PS-II.
• After the photosynthesis reaction, released products like glucose help in the transfer of electrons from PS-II to PS-I.
• After splitting water in PS-II, high-energy electrons are delivered through the chloroplast electron transport chain to PS-I.
• After the completion of the light-dependent reactions, the electrons are transferred from PS-II to PS-I.
• This event will have no effect on the rate of photosynthesis in the leaf.
• Photosynthesis in the leaf will slow down or possibly stop.
• Photosynthesis in the leaf will increase exponentially.
• Photosynthesis in the leaf will first decrease and then increase.
• The product of the Calvin cycle is glyceraldehyde-3 phosphate and RuBP is regenerated.
• The product of the Calvin cycle is glyceraldehyde-3 phosphate and RuBisCO is regenerated.
• The product of the Calvin cycle is a 3-PGA molecule and glyceraldehyde-3 phosphate is regenerated.
• The product of the Calvin cycle is glyceraldehyde-3 phosphate and oxygen is regenerated.
• by using CAM photosynthesis and by closing stomatal pores during the night
• by using CAM photosynthesis and by opening stomatal pores during the night
• by using CAM photosynthesis and by keeping stomatal pores closed at all times
• by bypassing CAM photosynthesis and by keeping stomatal pores closed at night
• The prey of lions are generally herbivores, which depend on heterotrophs.
• The prey of lions are generally smaller carnivorous animals, which depend on non-photosynthetic organisms.
• The prey of lions are generally herbivores, which depend on autotrophs.
• The prey of lions are generally autotrophs, which depend onother autotrophs.
• It takes three turns to fix enough oxygen to export one G3P molecule.
• It takes three turns to produce RuBisCO as an end product.
• It takes three turns to produce ATP and NADPH for fixation of G3P.
• It takes three turns to fix enough carbon to export one G3P molecule.

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BIOLOGY JUNCTION

Test And Quizzes for Biology, Pre-AP, Or AP Biology For Teachers And Students

AP Essay Questions

Draw a graph of these data and answer the following questions.

• What is the initial rate of this enzymatic reaction?
• What is the rate after 50 seconds? Why is it different from the initial rate?
• What would be the effect on product formation if the enzyme where heated to a temperature of 100° C for 10 minutes before repeating the experiment? Why?
• How might altering the substrate concentration affect the rate of the reaction? Why?
• How might altering the pH affect the rate of the reaction? Why?

4.  Enzymes are biological catalysts.

• Relate the chemical structure of an enzyme to its specificity and catalytic activity.
• Design a quantitative experiment to investigate the influence of pH or temperature on the activity of an enzyme.
• Describe what information concerning the structure of an enzyme could be inferred from your experiments.

Unit 3 (Cell Structure and Function, Cell division)

5.  Describe the fluid-mosaic model of a plasma membrane. Discuss the role of the membrane in the movement of materials through it by each of the following processes:

• Active transport
• Passive transport

6.  Describe the structure of a eukaryotic plant cell. Indicate the ways in which a nonphotosynthetic prokaryotic cell would differ in structure from this generalized eukaryotic plant cell.

7.  Discuss the process of cell division in animals. Include a description of mitosis and cytokinesis, and of the other phases of the cell cycle. Do Not include meiosis.

8.  A laboratory assistant prepared solution of 0.8 M, 0.6 M, 0.4 M, and 0.2 M sucrose, but forgot to label them. After realizing the error, the assistant randomly labeled the flasks containing these four unknown solutions as flask A, flask B, flask C, and flask D.

Design an experiment, based on the principles of diffusion and osmosis, that the assistant could use to determine which of the flasks contains each of the four unknown solutions. Include in your answer (a) a description of how you would set up and perform the experiment: (b) the results you would expect from your experiments: and (c) an explanation of those results based on the principles involved. (Be sure to clearly state the principles addressed in your discussion.)

9.  Cells transport substances across their membranes. Choose THREE of the following four types of cellular transport.

• Active Transport
• Facilitated Diffusion
• Endocytosis/exocytosis

For each of the three transport types you choose,

• Describe the transport process and explain how the organization of cell membranes functions in the movement of specific molecules across membranes; and
• Explain the significance of each type of transport to a specific cell (you may use difference cell types as examples.)

Unit 4 (Photosynthesis and Cellular Respiration)

10.  Describe the similarities and differences between the biochemical pathways of aerobic respiration and photosynthesis in eukaryotic cells. Include in your discussion the major reactions, the end products, and energy transfers.

11.  The rate of photosynthesis may vary with changes that occur in environmental temperature, wavelength of light, and light intensity. Using a photosynthetic organism of your choice, choose only ONE of the three variables (temperature, wavelength of light, or light intensity) and for this variable

• design a scientific experiment to determine the effect of the variable on the rate of photosynthesis for the organism;
• explain how you would measure the rate of photosynthesis in your experiment;
• describe the results you would expect. Explain why you would expect these results.

12.  Describe the light reactions of photosynthesis and, for both a C3 and a C4 plant, trace the path of a carbon dioxide molecule from the point at which it enters a plant to its incorporation into a glucose molecule. Include leaf anatomy and biochemical pathways in your discussion of each type of plant.

13.  Explain what occurs during the Krebs (citric acid) cycle and electron transport by describing the following:

• The location of the Krebs cycle and electron transport chain in mitochondria.
• The cyclic nature of the reactions in the Krebs cycle.
• The production of ATP and reduced coenzymes during the cycle.
• The chemiosmotic production of ATP during electron transport.

14.  Membranes are important structural features of cells.

• Describe how membrane structure is related to the transport of materials across the membrane.
• Describe the role of membranes in the synthesis of ATP in either cellular respiration or photosynthesis.

15. Energy transfer occurs in all cellular activities. For 3 of the following 5 processes involving energy transfer, explain how each functions in the cell and give an example. Explain how ATP is involved in each example you choose.

• cellular movement
• active transport
• synthesis of molecules
• chemiosmosis
• fermentation

16. The results below are measurements of cumulative oxygen consumption by germinating and dry seeds. Gas volume measurements were corrected for changes in temperature and pressure.

• Using the graph paper provided, plot the results for the germinating seeds at 22° C and at 10° C.
• Calculate function the rate of oxygen consumption for the germinating seeds at 22° C, using the time interval between 10 and 20 minutes.
• germinating seeds at 22° C and at 10° C
• germinating seeds and dry seeds
• Describe the essential features of an experimental apparatus that could be used to measure oxygen consumption by a small organism. Explain why each of these features is necessary.

Unit 5 (Meiosis, Mendelian Genetics, DNA Replication)

17.  State the conclusions reached by Mendel in his work on the inheritance of characteristics. Explain how each of the following deviates from these conclusions.

• Autosomal linkage.
• Sex-linked (X-linked) inheritance.
• Polygenic (multiple-gene) inheritance.

18.  Experiments by the following scientists provided critical information concerning DNA. Describe each classical experiment and indicate how it provided evidence for the chemical nature of the gene.

• Hershey and Chase- bacteriophage replication
• Griffith and Avery, MacLeod and McCarty- bacterial transformation
• Meselson and Stahl- DNA replication in bacteria

19.  Discuss Mendel’s laws of segregation and independent assortment. Explain how the events of meiosis I account for the observations that led Mendel to formulate these laws.

20.  An organism is heterozygous at two genetic loci on different chromosomes.

• Explain how these alleles are transmitted by the process of mitosis to daughter cells.
• Explain how these alleles are distributed by the process of meiosis to gametes.
• Explain how the behavior of these two pairs of homologous chromosomes during meiosis provides the physical basis for Mendel’s two laws of inheritance.

Labeled diagrams that are explained in your answer may be useful.

Unit 6 (Protein Synthesis, Gene Expression, DNA Technology)

21.  A portion of specific DNA molecule consists of the following sequence of nucleotide triplets.

TAC GAA CTT GGG TCC

This DNA sequence codes for the following short polypeptide.

methionine – leucine – glutamic acid – proline – arginine

Describe the steps in the synthesis of this polypeptide. What would be the effect of a deletion or an addition in one of the DNA nucleotides? What would be the effects of a substitution in one of the nucleotides?

22.  Describe the operon hypothesis and discuss how it explains the control of messenger RNA production and the regulation of protein synthesis in bacterial cells.

23.  Scientists seeking to determine which molecule is responsible for the transmission of characteristics from one generation to the next knew that the molecule must (1) copy itself precisely, (2) be stable but able to be changed, and (3) be complex enough to determine the organism’s phenotype.

• Explain how DNA meets each of the three criteria stated above.
• Select one of the criteria stated above and describe experimental evidence used to determine that DNA is the hereditary material.

24.  Describe the biochemical composition, structure, and replication of DNA. Discuss how recombinant DNA techniques may be used to correct a point mutation.

25.  Describe the production and processing of a protein that will be exported from a eukaryotic cell. Begin with the separation of the messenger RNA from the DNA template and end with the release of the protein at the plasma membrane.

26.  Describe the steps of protein synthesis, beginning with the attachment of a messenger RNA molecule to the small subunit of a ribosome and ending generalized with the release of the polypeptide from the ribosome. Include in your answer a discussion of how the different types of RNA function in this process.

27.  The diagram below shows a segment of DNA with a total length of 4,900 base pairs. The arrows indicate reaction sites for two restriction enzymes (enzyme X and enzyme Y).

• Explain how the principles of gel electrophoresis allow for the separation of DNA fragments.
• DNA digested with only enzyme X
• DNA digested with only enzyme Y
• DNA digested with enzyme X and enzyme Y combined
• Undigested DNA
• The mechanism of action of restriction enzymes.
• The different results you would expect if a mutation occurred at the recognition site for enzyme Y.

28.  By using the techniques of genetic engineering, scientists are able to modify genetic materials so that a particular gene of interest from one cell can be incorporated into a different cell.

• Describe a procedure by which this can be done.
• Explain the purpose of each step of your procedure.
• Describe how you could determine whether the gene was successfully incorporated.
• Describe an example of how gene transfer and incorporation have been used in biomedical or commercial applications.

29.  Assume that a particular genetic condition in a mammalian species causes an inability to digest starch. This disorder occurs with equal frequency in males and females. In most cases, neither parent of affected offspring has the condition.

• Describe the most probable pattern of inheritance for this condition. Explain your reasoning. Include in your discussion a sample cross(es) sufficient to verify your proposed pattern.
• Explain how a mutation could cause this inability to digest starch.
• Describe how modern techniques of molecular biology could be used to determine whether the mutant allele is present in a given individual.

Unit 7 (Evolution, Population Genetics, Speciation)

29.  Describe the special relationship between the two terms in each of the following pairs.

• Convergent evolution of organisms and Australia.
• Blood groups and genetic drift.
• Birds of prey and DDT.

30.  Describe the modern theory of evolution and discuss how it is supported by evidence from two of the following areas.

• population genetics
• molecular biology
• comparative anatomy and embryology

31.  Describe the process of speciation. Include in your discussion the factors that may contribute to the maintenance of genetic isolation.

32.  Do the following with reference to the Hardy-Weinberg model.

• Indicate the conditions under which allelic frequencies (p and q) remain constant from one generation to the next.
• Calculate, showing all work, the frequencies of the alleles and the frequencies of the genotypes in a population of 100,000 rabbits, of which 25,000 are white and 75,000 are agouti. (In rabbits the white color is due to a recessive allele, w, and the agouti is due to a dominant all, W.)
• If the homozygous dominant condition were to become lethal, what would happen to the allelic and genotypic frequencies in the rabbit population after two generations?

33.  Evolution is one of the major unifying themes of modern biology.

• Explain the mechanisms that lead to evolutionary change.
• Bacterial resistance to antibodies.
• Comparative biochemistry.
• The fossil record.

34.  Genetic variation is the raw material for evolution.

• Explain three cellular and/or molecular mechanisms that introduce variation into the gene pool of a plant or animal population.
• Explain the evolutionary mechanisms that can change the composition of the gene pool.

35.  In a laboratory population of diploid, sexually reproducing organisms a certain trait is studied. This trait is determined by a single autosomal gene and is expressed as two phenotypes. A new population was created by crossing 51 pure breeding (homozygous) dominant individuals with 49 pure breeding (homozygous) individuals. After four generations, the following results were obtained.

• Identify an organism that might have been used to perform this experiment, and explain why this organism is a good choice for conducting this experiment.
• On the basis of the data, propose a hypothesis that explains the change in phenotypic frequency between generation 1 and generation 3.
• Is there evidence indicating whether or not this population is in Hardy-Weinberg equilibrium? Explain.

 Unit 8 (Chemical Evolution, Prokaryotes, Eukaryote Evolution, Protista)

36.  Scientists recently have proposed a reorganization of the phylogenetic system of classification to include the domain, a new taxonomic category higher (more inclusive) than the Kingdom category, as shown in the following diagram.

Universal Ancestor

Domain Bacteria             Domain Archaea Domain Eukarya

(Eubacteria)             (Archaebacteria) (Eukaryotes)

• describe how this classification scheme presents different conclusions about the relationships among living organisms than those presented by the previous five-kingdom system of classification
• describe three kinds of evidence that were used to develop the taxonomic scheme above, and explain how this evidence was used. The evidence may be structural, physiological, molecular, and/or genetic.
• four of the characteristics of the universal ancestor.

Unit 9 (Introduction to Plants, Fungi, Invertebrates)

37.  In the life cycles of a fern and a flowering plant, compare and contrast each of the following:

• The gametophyte generation.
• Sperm transport and fertilization.
• Embryo protection.

38.  Describe the differences between the terms in each of the following pairs.

• Coelomate versus acoelomate body plan.
• Protostome versus deuterostome development.
• Radial versus bilateral symmetry.
• Explain how each of these pairs of features was important in constructing the phylogenetic tree shown below. Use specific examples from the tree in your discussion.

Unit 10 (Vertebrates, Basic Animal Structure and Function)

39.  Select two of the following three pairs and discuss the evolutionary relationships between the two members of each pair you have chosen. In your discussion include structural adaptations and the functional significance.

Pair A: green algae—vascular plants

Pair B: prokaryotes—eukaryotes

Pair C: amphibians—reptiles

Unit 11 (Animal Nutrition, Circulation, Respiration, Immune System)

40.  Describe the structure of a mammalian respiratory system. Include in your discussion the mechanisms of inspiration and expiration.

41.  Describe the processes of fat and protein digestion and product absorption as they occur in the human stomach and small intestine. Include a discussion of the enzymatic reactions involved.

42.  Describe the following mechanisms of response to foreign materials in the human body.

• The antigen-antibody response to a skin graft from another person.
• The reactions of the body leading to inflammation of a wound infected by bacteria.

43.  Discuss the processes of exchange of O2 and CO2 that occur at the alveoli and muscle cells of mammals. Include in your answer a description of the transport of these gases in the blood.

44.  Many physioligical changes occur during exercise.

• Design a controlled experiment to test the hypothesis that an exercise session causes short-term increases in heart rat and breathing rate in humans.
• Explain how at least three organ systems are affected by this increased physical activity and discuss interactions among these systems.

45.  The graph below shows the response of the human immune system to exposure to an antigen. Use this graph to answer part a and part b of this question.

• Describe the events that occur during period I as the immune system responds to the initial exposure to the antigen.
• Describe the events that occur during period II following a second exposure to the same antigen.
• Explain how infection by the AIDS virus (HIV) affects the function of both T and B lymphocytes.

Unit 12 (Homeostasis, Reproduction, Development)

47.  Discuss the processes of cleavage, gastrulation, and neurulation in the frog embryo; tell what each process accomplishes. Describe an experiment that illustrates the importance of induction in development.

48.  The evolutionary success of organisms depends on reproduction. Some groups of organisms reproduce asexually, some reproduce sexually, while others reproduce both sexually and asexually.

• Using THREE difference organisms, give an example of one organism that reproduces sexually, one that reproduces asexually, and one that reproduces BOTH sexually and asexually. For each organism given as an example, describe two reproductive adaptations. These adaptations may be behavioral, structural, and/or functional.
• What environmental conditions would favor sexual reproduction? Explain. What environmental conditions would favor asexual reproduction? Explain.

Unit 13 (Endocrine System, Nervous System, Sensory and Motor Mechanisms)

49.  Discuss the sources and actions of each of the following pairs of hormones in humans and describe the feedback mechanisms that control their release.

• Insulin—glucagon
• Parathyroid hormone—calcitonin
• Thyrotropin (TSH)—thyroxine (T4)

50.  Beginning at the presynaptic membrane of the neuromuscular junction, describe the physical and biochemical events involved in the contraction of a skeletal muscle fiber. Include the structure of the fiber in your discussion.

52.  Describe the negative and positive feedback loops, and discuss how feedback mechanisms regulate each of the following.

• The menstrual cycle in nonpregnant human female.
• Blood glucose levels in humans.

53.  Discuss how cellular structures, including the plasma membrane, specialized endoplasmic reticulum, cytoskeletal elements, and mitochondria, function together in the contraction of skeletal muscle cells.

54.  Structure and function are related in the various organ systems of animals. Select two of the following four organ systems in vertebrates:

• respiratory

For each of the two systems you choose, discuss the structure and function of two adaptations that aid in the transport or exchange of molecules (or ions). Be sure to relate structure to function in each example.

Unit 14 (Plant Structure and Function)

55.  Relate the structure of an angiosperm leaf to each of the following:

• Adaptations for photosynthesis and food storage.
• Adaptations for food translocation and water transport.
• Specialized adaptations to a desert environment.

56.  Define the following plant responses and explain the mechanism of control for each. Cite experimental evidence as part of your discussion.

• Phototropism
• Photoperiodism

57.  Describe the structure of a bean seed and discuss its germination to the seedling stage. Include in your essay hormonal controls, structural changes, and tissue differentiation.

58.  Describe the effects of plant hormones on plant growth and development. Design an experiment to demonstrate the effect of one of these plant hormones on plant growth and development.

59.  Trace the pathway in a flowering plant as the water moves from the soil through the tissues of the root, stem, and leaves to the atmosphere. Explain the mechanisms involved in conducting water through these tissues.

60.  Discuss the adaptations that have enabled flowering plants to overcome the following problems associated with life on land.

• The absence of an aquatic environment for reproduction.
• The absence of an aquatic environment to support the plant body.
• Dehydration of the plant.

61.  A group of students designed an experiment to measure transpiration rates in a particular species of herbaceous plant. Plants were divided into four groups and were exposed to the following conditions.

The cumulative water loss due to transpiration of water from each plant was measured at 10-minute intervals for 30 minutes. Water loss was expressed as milliliters of water per square centimeter of leaf surface area. The data for all plants in Group I (room conditions) were averaged. The average cumulative water loss by the plants in Group I is presented in the table below.

• Construct and label a graph using the data for Group I. Using the same set of axes, draw and label three additional lines representing the results that you would predict for Groups II, III, and IV.
• Explain how biological and physical processes are responsible for the difference between each of your predictions and the data for Group I.
• Explain how the concept of water potential is used to account for the movement of water from the plant stem to the atmosphere during transpiration.

62.  Numerous environmental variables influence plant growth. Three students each planted a seedling of the same genetic variety in the same type of container with equal amounts of soil from the same source. Their goal was to maximize their seedling’s growth by manipulating environmental conditions. Their data are shown below.

• Identify three different environmental variables that could account for differences in the mass of seedlings at day 30. Then choose one of these variables and design an experiment to test the hypothesis that your variable affects growth of these seedlings.
• Discuss the results you would expect if your hypothesis is correct. Then provide a physiological explanation for the effect of your variable on plant growth.

Unit 15 (Ecology)

63.  Define and explain the role of each of the following in social behavior.

• Territoriality.
• Dominance hierarchies.
• Courtship behavior.

64.  Describe the trophic levels in a typical ecosystem. Discuss the flow of energy through the ecosystem, the relationship between the different trophic levels, and the factors that limit the number of trophic levels.

65.  Describe and give an example of each of the following. Include in your discussion the selection advantage of each.

• Pheromones.
• Stereotyped behavior (instinct).

66.  Describe the process of ecological succession from a pioneer community to a climax community. Include in your answer a discussion of species diversity and interactions, accumulation of biomass, and energy flow.

67.  Describe releasers, imprinting, and communications, as each of these terms relates to animal behavior. You may include in your answer a discussion of the classical studies of Niko Tinbergen, Konrad Lorenz, and Karl von Frisch.

68.  Describe the biogeochemical cycles of carbon and nitrogen. Trace these elements from the point of their release from a decaying animal to their incorporation into a living animal.

69.  Using an example for each, discuss the following ecological concepts.

• Energy flow between trophic levels.
• Limiting factors.
• Carrying capacity.

70.  Living organisms play an important role in the recycling of many elements within an ecosystem. Discuss how various types of organisms and their biochemical reactions contribute to the recycling of either carbon or nitrogen in an ecosystem. Include in your answer one way in which human activity has an impact in the nutrient cycle you have chosen.

71.  Survival depends on the ability of an organism to respond to changes in its environment. Some plants flower in response to changes in day length. Some mammals may run or fight when frightened. For both of these examples, describe the physiological mechanisms involved in the response.

72.  Interdependence in nature is illustrated by the transfer of energy through trophic levels. The diagram below depicts the transfer of energy in a food web of an Arctic lake located in Alaska (J )

• Choosing organisms from four different trophic levels of this food web as examples, explain how energy is obtained at each trophic level.
• Describe the efficiency of energy transfer between trophic levels and discuss how the amount of energy available at each trophic level affects the structure of the ecosystem.
• If the cells in the dead terrestrial plant material that washed into the lake contained a commercially produced toxin, what would be the likely effects of this toxin on this food web? Explain.

For the data above, provide information on each of the following.

• Summarize the pattern.
• Identify THREE physiological or environmental variables that could cause the slugs to vary their distance from each other.
• Explain how each variable could bring about the observed pattern of distribution.

Choose ONE of the variables that you identified and design a controlled experiment to test your hypothetical explanation. Describe results that would support or refute your hypothesis.

Cumulative Essays

74.  Describe how the following adaptations have increased the evolutionary success of the organisms that possess them. Include in your discussion the structure and function related to each adaptation.

• C4 metabolism
• Amniotic egg
• Four-chambered heart

75.  Describe the anatomical and functional similarities and difference within each of the following pairs of structures.

• Artery—vein
• Small intestine—colon
• Skeletal muscle—cardiac muscle
• Anterior pituitary—posterior pituitary

76.  Discuss how each of the following has contributed to the evolutionary success of the organisms in which they are found.

• mammalian placenta

77.  Angiosperms (flowering plants) and vertebrates obtain nutrients from their environment in different ways.

• Discuss the type of nutrition and the nutritional requirements of angiosperms and vertebrates.
• Describe 2 structural adaptations in angiosperms for obtaining nutrients from the environment. Relate structure to function.
• Interdependence in nature is evident in symbiosis. Explain tow symbiotic relationships that aid in nutrient uptake, using examples from angiosperms and/or vertebrates. (Both examples may be angiosperms, both may be vertebrates, or one may be from each group.

78.  The problem of survival of animals on land are very different from those of survival of animals in an aquatic environment. Describe four problems associated with animal survival in terrestrial environments but not in aquatic environments. For each problem, explain an evolutionary solution.

79.  The survival of organisms depends on regulatory mechanisms at various levels. Choose THREE from the following examples. Explain how each is regulated.

• The expression of a gene.
• The activity of an enzyme.
• The cell cycle.
• The internal water balance of a plant.
• The density of a population.

80.  Photosynthesis and cellular respiration recycle oxygen in ecosystems. Respond to TWO (and only two) of the following:

• Explain how the metabolic processes of cellular respiration and photosynthesis recycle oxygen.
• Discuss the structural adaptations that function in oxygen exchange between each of the following organisms and its environment: a plant; an insect; a fish.
• Trace a molecule of O2 from the environment to a muscle cell in a vertebrate of your choice.

81.  Biological recognition is important in many processes at the molecular, cellular, tissue, and organismal levels. Select three of the following, and for each of the three that you have chose, explain how the process of recognition occurs and give an example of each.

• Organisms recognize others as members of their own species.
• Neurotransmitters are recognized in the synapse.
• Antigens trigger antibody response.
• Nucleic acids are complementary.
• Target cells respond to specific hormones.

82.  Communication occurs among the cells in a multicellular organism. Choose THREE of the following examples of cell-to-cell communication, and for each example, describe the communication that occurs and the types of responses that result from this communication.

• communication between two plant cells
• communication between two immune-system cells
• communication either between a neuron and another neuron, or between a neuron and a muscle cell
• communication between a specific endocrine-gland cell and its target cell

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Photosynthesis: Essay on Photosynthesis (2098 Words)

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Here is your essay on Photosynthesis!

[I] Photosynthesis:

Photosynthesis is one of the most fundamental biological reactions.

The chlorophyll bearing plants trap the free energy of sunlight as photons and transform and store it as chemical potential energy by combining CO 2 and water.

The end products of photosynthesis are carbohydrates with loss of oxygen. These directly or indirectly serve as the source of energy for all living beings, except chemosynthetic bacteria.

Image Courtesy : co2crc.com.au/Photosynthesis_media.jpg

[II] Food storage :

Some unpigmented plastids like leucoplasts store the essential food materials like protein, oil and starch. Later on these are used during germination of seeds and development.

[III] Hereditary carrier :

Recent studies show that these plastids, like chromosomes, are transmitted directly to the daughter cells during cell division. Cytoplasmic inheritance of plastids in Mirabilis is the well-known example. They produce phenotypic effects in Oenothera and other plants.

[IV] Chloroplasts as semiautonomous organoid :

The chloroplast matrix contains dissolved salts and enzymes of photo­synthesis. Besides these, like mitochondria, it contains RNA, DNA and ribosomes, and is capable of carrying on protein synthesis.

The chloroplast ribosomes are of the same size as ribosomes in prokaryotes. Chloroplasts are also semi-autonomous like mitochondria. They can grow and divide, and their DNA contains a portion of the genetic information needed for the synthesis of chloroplast proteins.

[V] Inheritance of chloroplasts :

Cells have the capacity to outgrow their chloroplasts and the rate of multiplication of chloroplasts is partly independent of the rate of multiplication of entire cells. Brawerman and Chargaff (1960) discovered it in Euglena gracilis after a temperature shock.

Cells which were permitted to multiply rapidly became irreversibly bleached, whereas cells prevented from dividing regained their normal ability to produce chloroplasts. They concluded that Euglena contains an autonomously replicating factor which is necessary for chloroplast formation.

[VI] DNA in chloroplasts :

Chloroplasts contain both DNA and the necessary mechanism for synthesizing specific RNA’s and proteins from a DNA template. DNA is found in chloroplasts (Stocking and Gifford, 1959). Ris and Plaut (1962) have also found DNA in the chloroplasts of alga Chlamydomonas. It has now been generally accepted that characteristic chloroplast DNA’s or chloroplast chromosomes occur in the photosynthetic organelles of algae and higher plants.

According to Brawerman (1966) this DNA differs from nuclear DNA in GC (guanosine and cytosine) content. Chloroplasts also contain a DNA-dependent RNA polymerase; it appears that specific RNA’s are synthesized from chloroplast DNA as a template (Kirk 1966). Chloroplasts DNA are capable of self-duplication.

[VII] Chloroplast ribosomes :

Lyttleton (1962) isolated chloroplast ribosomes, which are estimated to make up 3 to 7% of the chloroplast dry mass. Chloroplast ribosomes are smaller than cytoplasmic ribosomes. These are 60-66S. Chloroplast ribosomes also dissociate reversibly into 50S and 35S subunits, in a way that is found in E. coli ribosomes (Boardman et al., 1966). Chloroplasts have three types of RNA required for protein synthesis: ribosomal, transfer and messenger. Chloroplast ribosomes associate to form polysomes for synthesis of proteins (Gunning and Steer, 1975).

[VIII] Protein synthesis :

Protein synthesis in mitochondria and chloroplasts is similar to that of prokaryotes. For example, the size of chloroplast ribosomes is the same as ribosomes of blue-green algae, and ribosomes of chloroplasts and mitochondria more closely resemble prokaryotic ribosomes in antibiotic sensitivity than they do eukaryotic ribosomes.

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Photosynthesis and Cellular Respiration Essay

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Photosynthesis is one of the primary sources of energy for living organisms. The fossilized photosynthetic fuels account for almost 90% of the energy in the world (Johnson, 2016). Cellular respiration is a process that takes place in the living organism and converts nutrients into energy. This essay will examine photosynthesis and cellular respiration separately and identify similarities, differences, and interconnectedness between two processes. Two processes are similar in that they both deals with energy, but they are different because one process involves catabolic reactions and another anabolic one.

The purpose of photosynthesis is to convert atmospheric carbon dioxide into carbohydrates using light energy. The light splits one of the reactants, water in the mesophyll of the leaf into oxygen, electrons, and protons during the light-dependent phase (Johnson, 2016). Then carbon dioxide enters the mesophyll of the leaf through openings, stomata, during the light-independent phase. These two reactions differ in light utilization and molecules production. The first reaction products are oxygen, adenosine triphosphate (ATP), and nicotinamide adenine dinucleotide phosphate (NADPH) that are used as energy storages, while by the end of the second reaction, the carbohydrate is obtained, and molecules mentioned above are used (Flügge et al., 2016). Photosynthesis occurs in the chloroplast with the light-dependent reaction taking place in the thylakoid membrane, and light-independent reaction in the stroma. The energy produced in the light reaction is used to fix carbon dioxide and produce carbohydrates while oxygen is released outside. According to the following equation of the photosynthesis, C → O2 + 2H20 + photons (CH2O)n + electrons + O2 carbon monoxide and water are transferred into carbohydrates under the light with the release of atmospheric oxygen.

The purpose of cellular respiration is to convert nutrients into energy. The reactants of the respiration are glucose circulating in the blood and oxygen obtained from breathing, while the product is ATP. Cellular respiration starts from glycolysis in the mitochondria’s stroma, where the glucose is broken down into pyruvate (Bentley & Connaughton, 2017). Then it continues with the citric acid cycle that generates ATP, NADH, and FADH2. In the final stage, the electron transport chain uses these molecules to generate more ATP. The energy produced is then used for metabolic processes in the organism, while carbon dioxide is released with breathing (BBC Bitesize, n.d.). According to the following equation of the cellular respiration, C → 6H12O6 + 6O2 6CO2 + 6H2O the glucose is broken down into carbon dioxide and water with the presence of oxygen.

There are two main differences between photosynthesis and cellular respiration. The first one is the anabolic process, during which complex compounds are synthesized, while the second one is catabolic, which involves breaking down the compounds (Panawala, 2017). The second crucial difference is that photosynthesis is found only in chloroplasts, while cellular respiration is found in any living cell, making it a universal process. There are also two main similarities between photosynthesis and respiration. The first similarity is that both processes involve the production of ATP (Stauffer et al., 2018). The second similarity is that both processes utilize ATP but for different purposes.

Photosynthesis and cellular respiration are connected in such a way that they allow to perform metabolic functions normally. Moreover, these processes help to regulate the concentration of oxygen and carbon dioxide in the atmosphere. If photosynthesis stopped occurring, the level of oxygen would drop dramatically This would lead to deaths of all living organisms whose lives depend on this molecule. Whereas if cellular respiration stopped happening, living creatures would not be able to generate energy and sustain life.

To conclude, photosynthesis plays a crucial role in maintaining life on Earth. Photosynthesis uses light energy to produce oxygen, while cellular respiration uses oxygen to break down complex molecules and provide energy. These processes are different in their metabolic nature, but similar in terms of energy storage. If photosynthesis did not exist, the life for oxygen-dependent creatures would become extinct. Similarly, in the case of cellular respiration disappearing, living organisms would not be able to produce energy.

BBC Bitesize . (n.d.). Respiration. 2020. Web.

Bentley, M., & Connaughton, V, P. (2017). A simple way for students to visualize cellular respiration: Adapting the board game MousetrapTM to model complexity . CourseSource. 4, 1-6. Web.

Flügge, W., Westhoff, P., & Leister, D. (2016). Recent advances in understanding photosynthesis. F1000 Research, 5, 1-10.

Johnson, M. P. (2016). Photosynthesis. Essays Biochemistry , 60 (3), 255-273.

Panawala, L. (2017). Difference between photosynthesis and respiration. IE PEDIAA. Web.

Stauffer S., Gardner A., Ungu D.A.K., López-Córdoba A., & Heim M. (2018). Cellular respiration. In Labster virtual lab experiments: Basic biology (pp. 43-55). Springer.

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Essay on Photosynthesis

Students are often asked to write an essay on Photosynthesis in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Photosynthesis

What is photosynthesis.

Photosynthesis is how plants make their own food using sunlight. It happens in the leaves of plants. Tiny parts inside the leaves, called chloroplasts, use sunlight to turn water and carbon dioxide from the air into sugar and oxygen. The sugar is food for the plant.

The Ingredients

The main things needed for photosynthesis are sunlight, water, and carbon dioxide. Roots soak up water from the soil. Leaves take in carbon dioxide from the air. Then, using sunlight, plants create food and release oxygen.

The Process

In the chloroplasts, sunlight energy is changed into chemical energy. This energy turns water and carbon dioxide into glucose, a type of sugar. Oxygen is made too, which goes into the air for us to breathe.

Why It’s Important

Photosynthesis is vital for life on Earth. It gives us food and oxygen. Without it, there would be no plants, and without plants, animals and people would not survive. It also helps take in carbon dioxide, which is good for the Earth.

250 Words Essay on Photosynthesis

Why is photosynthesis important.

This process is very important because it is the main way plants make food for themselves and for us, too. Without photosynthesis, plants could not grow, and without plants, animals and humans would not have oxygen to breathe or food to eat.

How Photosynthesis Works

Photosynthesis happens in two main stages. In the first stage, the plant captures sunlight with its leaves. The sunlight gives the plant energy to split water inside its leaves into hydrogen and oxygen. The oxygen is released into the air, and the hydrogen is used in the next stage.

In the second stage, the plant mixes the hydrogen with carbon dioxide from the air to make glucose, which is a type of sugar that plants use for energy. This energy helps the plant to grow, make flowers, and produce seeds.

The Cycle of Life

Photosynthesis is a key part of the cycle of life on Earth. By making food and oxygen, plants support life for all creatures. When animals eat plants, they get the energy from the plants, and when animals breathe, they use the oxygen that plants release. It’s a beautiful cycle that keeps the planet alive.

500 Words Essay on Photosynthesis

Photosynthesis is a process used by plants, algae, and some bacteria to turn sunlight, water, and carbon dioxide into food and oxygen. This happens in the green parts of plants, mainly the leaves. The green color comes from chlorophyll, a special substance in the leaves that captures sunlight.

The Ingredients of Photosynthesis

The photosynthesis recipe.

When sunlight hits the leaves, the chlorophyll captures it and starts the food-making process. The energy from the sunlight turns water and carbon dioxide into glucose, a type of sugar that plants use for energy, and oxygen, which is released into the air. This process is like a recipe that plants follow to make their own food.

The Importance of Photosynthesis

Photosynthesis is very important for life on Earth. It gives us oxygen, which we need to breathe. Plants use the glucose they make for growth and to build other important substances like cellulose, which they use to make their cell walls. Without photosynthesis, there would be no food for animals or people, and no oxygen to breathe.

The Benefits to the Environment

Photosynthesis and the food chain.

All living things need energy to survive, and this energy usually comes from food. Plants are at the bottom of the food chain because they can make their own food using photosynthesis. Animals that eat plants get energy from the glucose in the plants. Then, animals that eat other animals get this energy too. So, photosynthesis is the start of the food chain that feeds almost every living thing on Earth.

Photosynthesis in Our Lives

Photosynthesis affects our lives in many ways. It gives us fruits, vegetables, and grains to eat. Trees and plants also give us wood, paper, and other materials. Plus, they provide shade and help make the air fresh and clean.

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Photosynthesis - Essay Examples And Topic Ideas For Free

Photosynthesis is the process by which green plants, algae, and some bacteria convert sunlight, carbon dioxide, and water into food and oxygen. Essays might explore the biochemical process of photosynthesis, its importance to life on Earth, and the ongoing scientific research in enhancing or mimicking photosynthesis. A vast selection of complimentary essay illustrations pertaining to Photosynthesis you can find at PapersOwl Website. You can use our samples for inspiration to write your own essay, research paper, or just to explore a new topic for yourself.

What is Photosynthesis?

Photosynthesis is the process that transforms organisms from light energy into chemical energy. In order for photosynthesis to take place, it needs these three things: Water, carbon dioxide, and sunlight. As humans, in order to live plants, must take in gases. Plants are known as ""autotrophs, which means organisms that can make their own food. The process of photosynthesis was created and developed Jan Ingenhousz, a British physician and scientist. Joseph Priestley was another scientist who contributed to the discovery […]

Photosynthesis Vs. Cellular Respiration the Major Processess in a Global Balance

There are two key processes that occur in nature to obtain energy, they are photosynthesis and cellular respiration. The derivative of the word photosynthesis is the process in which energy of sunlight is converted by plants to store chemical energy in carbohydrate bonds. Photosynthesis is known to be performed by plants, as is cellular respiration. Cellular respiration is organisms obtaining energy from a conversation that releases energy when oxygen is present. These two processes work together hand in hand as […]

Effects of Sweet Cassava Polysaccharide

The study I researched was the ""Effects of sweet cassava polysaccharide extracts on endurance exercise in rats. Sweet cassava is a major carbohydrate in many countries and it contains monosaccharides and polysaccharides. It was found that high-carbohydrate foods could increase muscle glycogen content, which can allow one to exercise for a longer time and not tire as quickly. The aim of the study was to examine the effects of the sweet cassava polysaccharides (SCP) on exercise performance in rats. The […]

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Process of Photosynthesis

Presentation Photosynthesis, process by which green plants and certain different living beings utilize the vitality of light to change over carbon dioxide and water into the basic sugar glucose. In this manner, photosynthesis gives the fundamental vitality source to basically all life forms. A critical result of photosynthesis is oxygen, on which most living beings depend. Photosynthesis happens in green plants, ocean growth, green growth, and certain microscopic organisms. These living beings are veritable sugar plants, creating a huge number […]

Why is Photosynthesis Important?

"Photosynthesis is an important process which allows organisms to produce food without the intervention of any other organisms. This specialized reaction, occurring only in autotrophs, has several key features that are fundamental for understanding the process as a whole. Factors of where the process takes place, the reactants and products of the reactions, and what happens in the process are all important elements in the success of photosynthesis. Photosynthesis occurs in the chloroplast, an organelle found only in plant cells. […]

How to Relieve Global Warming by Carbon Dioxide Capture and Storage

Introduction 'US President Donald Trump has cast doubt on a report by his own government warning of devastating effects from climate change.' (BBC News,26 November 2018) Several months ago, Donald Trump claims that the America exit 'Paris Agreement' because he think Global Warming is the lie of the scientists. Does he is true? The tables below show: 'On the Linearity of Local and Regional Temperature Changes from 1.5°C to 2°C of Global Warming.' Fig. 1. 30% rise in atmospheric CO2 […]

Photosynthesis Virtual Lab

Hypothesis: all of the colors in the light spectrum are most effective in the growth process of photosynthesis except for green. We tested our hypothesis by plugging in the different colors as well as the different types of plants into the simulation. After running the simulation we gathered the info of the averages in lengths of the plants after 30 days. The variables we controlled in this experiment were the pot, type of soil, location, and amount of water given. […]

Idea of Photosynthesis by Jan Ingenhousz

To begin, the idea of photosynthesis was created by, according to Encyclopaedia Britannica, ""A Dutch scientist, Jan Ingenhousz. (Ingenhousz 1.) He was born in the Netherlands on December 8, 1730. Ingenhousz, is most known for his discovery of photosynthesis. According, to Encyclopedia Britannica, ""Ingenhousz discovered that light is necessary for photosynthesis, only the green parts of the plant perform photosynthesis, and all living parts of the plant can potentially damage the air."" (Ingenhousz 1.) Photosynthesis occurs in two steps inside […]

Photosynthesis in Living Leaves

Abstract The rate of photosynthesis can be measured by examining the amount of reactants and the buildup of products. Oxygen is a product of photosynthesis and is stored in the spongy mesophyll. This gives the organism the ability to float. In this experiment, oxygen is taken out of the spongy mesophyll. The leaves are then placed into the bicarbonate solution with soapy water. The spongy mesophyll fills with the solution, causing the leaves to sink. A light source was placed […]

Photosynthesis and Energy

Energy is very important and plays a substantial role in life itself, but where does energy come from, and how does energy work? Of course, the answer is simple: photosynthesis. With this reading, you will learn what photosynthesis is, how it works, the energy it creates, and how energy is stored and used. Finally, you will learn about different types of energy and the benefits those energy sources have. The process of photosynthesis begins when a plant receives carbon dioxide […]

Photosynthesis and Cellular Respiration: the Pillars of Life’s Energy Cycle

The basic ecological processes of photosynthesis and cellular respiration maintain the delicate balance of life within the complex web of interrelated creatures that makes up our planet. Although these creatures have different ecological functions, they are interrelated and help to maintain the delicate ecological balance of our world. The complex relationship between photosynthesis and cellular respiration is explained in this article, emphasizing how they work together harmoniously to support life. Green plants, algae, and certain bacteria engage in the complex […]

Energy Efficiency of Photosynthesis

Photosynthesis is the process in which plants use the energy from the sunlight to make glucose (a type of sugar), which they then use as food. The equation for photosynthesis is: 6CO2 (carbon dioxide) +6H2O (water) -->(Sunlight) C6H12O6 (glucose) +6O2 (oxygen). Plants, algae, and cyanobacteria are photosynthetic organisms. In plants and algae, light is absorbed by chlorophyll—a molecule present in the cytoplasmic organelle called the chloroplast. Chlorophyll has a porphyrin ring with a magnesium cofactor at its center. Plants have […]

Photosynthesis: Nature’s Genius in a Simple Equation

Plants in a high-stakes cooking show, but instead of whipping up a gourmet meal, they're busy cooking up something even more crucial – oxygen and energy. Welcome to the world of photosynthesis, nature's ingenious process that's all about transforming sunlight into life. And the secret recipe? It's hidden in a simple yet remarkable chemical equation. Here's the lowdown: photosynthesis is like a magic trick where plants take carbon dioxide (CO2) and water (H2O), add a splash of sunlight, and voilà […]

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IB DP Biology Topic 8 :8.3 Photosynthesis Question Bank HL Paper 2

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Describe the process of photolysis in photosynthesis.

a. water is split/breaks

b. using  energy  from light

c. electrons «from photolysis» pass to  photosystem II

d. oxygen is a «waste» product

e. hydrogen ions/protons are produced

Allow answer given as an equation

[Max 3 Marks]

In ecosystems, energy is used to convert inorganic compounds into organic matter. Energy enters ecosystems through producers. 

Explain the processes by which light energy is converted into chemical energy.

Describe how energy flows through and is used by organisms in ecosystems.

a. plants/producers/autotrophs convert light to chemical energy by  photosynthesis

b. chlorophyll/photosynthetic pigments absorb light

c. electrons are excited/raised to higher energy level

d. excited electrons pass along chain of electron carriers

e. energy from electrons used to pump protons across thylakoid membrane/into thylakoid space

f. chemiosmosis/proton gradient used to make ATP

g. ATP synthase generates ATP

h. pigments arranged in photosystems

i. electrons from Photosystem II flow via the electron chain to Photosystem I

j. electrons from Photosystem I are used to reduce NADP

k. ATP and reduced NADP used in the light independent reactions/Calvin cycle

l. carbohydrate/glucose/carbon compounds produced containing energy

Award marking points for any point made on a clearly annotated diagram.

a. producers/plants/autotrophs obtain energy from light/sun/inorganic sources

b. food contains energy / energy passed in the form of food/carbon compounds (along food chains/between trophic levels)

c. consumers obtain energy from other organisms/from previous trophic level 

This mark point distinguishes consumers from producers.

d. energy released (in organisms) by (cell) respiration 

Reject energy used in respiration.

e. ATP produced

f. energy/ATP used for biosynthesis/movement/active transport/other valid use of ATP

g. less energy available / energy lost at each trophic level

Identify the following processes as  either  anabolism  or  catabolism by placing a tick (√) in the correct box.

Outline the importance of enzymes to metabolic processes.

a. increase rate of reaction/speed up reaction

b. lower  activation  energy

c. a specific enzyme for each reaction/substrate

d. metabolic process/pathway blocked if an enzyme is inhibited/absent

e. end-product inhibition can control metabolic pathways

f. differences in metabolism as cells produce different enzymes during differentiation

Explain chemiosmosis as it occurs in photophosphorylation.

Draw an annotated graph of the effects of light intensity on the rate of photosynthesis.

Using a  named  example of a genetically modified crop, discuss the specific ethical issues of its use.

Remember, up to TWO “quality of construction” marks per essay.

a.  photophosphorylation  is the production of ATP; b. (some of the) light absorbed by chlorophyll / photosystem II; c. photolysis/splitting of water separation of hydrogen ion from its electron; d. the electron transport system moves the electrons through a series of carriers; e. (electron transport system occurs) in the thylakoid membrane; f. electron transport linked to movement of protons into thylakoid space; g. a proton gradient builds up (in the thylakoid space); h. small thylakoid space enhances the gradient; i. hydrogen ions move by diffusion through the ATP synthase; j. ADP + inorganic phosphate (Pi) forms ATP; k. (the kinetic energy from) movement of hydrogen ions (through ATP synthase) generates ATP; l. ATP synthase is a protein complex in the thylakoid membrane; m. formation of proton gradient / ATP synthesis linked to electron transport is chemiosmosis;

Award marks for a clearly drawn correctly annotated diagram.

a. vertical axis labelled as “rate of photosynthesis” and horizontal axis labelled as “light intensity”; b. drawn showing that at low light intensities, increased intensity leads to increased rate of photosynthesis (sharply); c. drawn with plateau formed at high light intensities; d. plateau annotated as maximum rate of photosynthesis; e. curve intersecting horizontal axis at a value above zero; f. arrows added to axes or student annotates axis with “rate of photosynthesis increases” and “light intensity increases”

a. named example of verified genetically modified crop;  eg , Bt corn / golden rice; Example must be verifiable. b. specific gene added / new protein synthesized by the crop plant / specific modification;  eg  gene from  Bacillus thuringiensis  / cry protein; c. biological effect of the modification;  eg , makes the plant toxic to (herbivorous) insects / insect pests / corn borers; [2 max]  for benefits and  [2 max ] for harmful effects / costs;

d. a benefit of specific genetic modification;  eg , increased crop yields / less land needed; e. a second benefit of this specific modification;  eg , reduced need for use of chemical pesticides; f. a harmful effect of specific genetic modification; ingestion of toxin by nontarget species; g. another specific harmful effect;  eg , concerns about contamination of neighbouring non-GMO crops affecting trade;

To award  [6]  responses need to address the name, description and the effect of the modification. Effects have to be linked to the specific example discussed. Marks have to be all linked to one example. Assistant examiners are required to research examples.

Draw a labelled diagram to show the structure of the plasma membrane.

The light-dependent reactions in photosynthesis take place on the thylakoid membranes. Explain the light-dependent reactions.

 Outline two factors that affect the rate of photosynthesis.

Award  [1]  for each structure clearly drawn and correctly labelled. a.  phospholipid bilayer  –  with head and tails ; b. hydrophilic/phosphate/polar heads  and  hydrophobic/hydrocarbon/fatty acid/non-polar tails labelled; c.  integral/intrinsic protein  –  embedded in the phospholipid bilayer ; d.  protein channel  –  integral protein showing clear channel/pore ; e.  peripheral/extrinsic protein  –  not protruding into the hydrophobic region ; f.  glycoprotein  with carbohydrate attached –  carbohydrate should be outside the bilayer ; g.  cholesterol  –  positioned across one half of bilayer and not protruding ; h. thickness indicated (10 nm);  (allow answers in the range of 7 nm to 13 nm)

a. (chlorophyll/pigments/antenna complex) in photosystem II  absorb  light; b. light/photoactivation produces an excited/high energy/free electron; c. electrons pass from carrier to carrier/along electron transport chain/e.t.c.; d. protons pumped across thylakoid membrane/into thylakoid space; e. ATP produced (by the light dependent reactions); f. ATP production by  chemiosmosis /by  ATP synthase/ATP synthetase ; g. electrons from photosystem II passed to photosystem I; h. light/photoactivation excites electrons in photosystem I (to higher energy level); i. production of NADPH/reduction of NADP (+)  (using electrons from photosystem I); (reject NAD in place of NADP. Accept reduced NADP instead of NADPH) j. electrons from photolysis (needed) for photosystem II; k. oxygen from photolysis is a waste product/by-product/passes out/excreted; l. in cyclic photophosphorylation electrons from photosystem I return to it;

a. (increase in) light (intensity) increases rate (of photosynthesis); b. until a plateau is reached at higher light intensities/when another factor is limiting; c. light needed for light dependent reactions/example of light dependent reaction; d. (increase in) temperature/heat increases the rate (of photosynthesis); e to an optimum temperature above which the rate drops; f. temperature/heat affects rate of Calvin cycle/enzyme activity/rubisco activity; g. (increase in) carbon dioxide (concentration) increases rate (of photosynthesis); h. until a plateau is reached at higher CO 2  levels/when another factor is limiting; i. CO 2  needed for light independent reactions/Calvin cycle/carboxylation of RuBP/production of glycerate phosphate;

If the candidate outlines more than two factors, only mark the first two. Accept the first two points relating to each factor if clearly shown on a graph with both axes appropriately labelled. Accept level instead of concentration, intensity or rate. Do not accept enzyme denaturation as a reason for reductions in photosynthesis at higher temperatures.

Isoprene is a chemical synthesized and emitted in large amounts by some plant species,  especially oak ( Quercus sp. ) and poplar ( Populus sp .) trees.  It has been suggested that isoprene increases the tolerance of plants to high temperatures, which can cause a decrease in photosynthesis rates. Black poplar ( Populus nigra ) plants were subjected to two raised temperatures and  to drought.  Measurements of photosynthesis and isoprene emission were made during a 35-day-long drought stress (drought period) and 3 and 15 days after re-watering stressed plants  (recovery period).  The rate of photosynthesis was recorded as the carbon dioxide taken up per unit of leaf area per second.

The effect of isoprene on photosynthesis was assessed in detached oak leaves that were supplied either water (control) or fosmidomycin dissolved in water.  Fosmidomycin inhibits the emission of isoprene without affecting photosynthesis. The measurements were taken at  30°C, but at three points in the experiment the leaves were subjected to heat treatment of 46°C (indicated on the graph by the arrows).  The rate of photosynthesis was measured as uptake of  CO 2  in μmol m –2  s –1

To test the effect of isoprene on a plant that does not normally produce it, leaves of common beans ( Phaseolus vulgaris ) were treated with heat stress at 46°C and were supplied with isoprene in the airstream.  The percentage recovery compares the rate of photosynthesis before and after heat treatment.  The data show the recovery of photosynthesis at different isoprene concentrations 1 hour and 24 hours after the heat treatment.

Suggest  one  method other than measuring CO 2  uptake by which the rate of photosynthesis could have been measured in these experiments.

Suggest why heat treatment may reduce photosynthesis rates.

Outline the effect of drought and of re-watering on the rate of photosynthesis.

Describe the isoprene emissions during the drought and recovery periods at 25°C.

Compare the effect of the two temperatures on the emission of isoprene.

State the effect of heat treatment on the rate of photosynthesis.

Using the results in the graph, deduce the effect of the presence of fosmidomycin on the rate of photosynthesis in the leaves.

Suggest possible conclusions for this experiment.

State the difference in percentage recovery of photosynthesis 1 hour after heat treatment between the 22 μL dm –3  isoprene treatment and the 0 μL dm –3  isoprene treatment.

Explain the evidence provided by the data in the bar chart for the hypothesis that isoprene improves plants’ tolerance to high temperatures.

Suggest  two  reasons for some plant species synthesizing and emitting isoprene, but not other plant species such as common beans.

oxygen production/release; ( not count bubbles ) production/increase/change/ measurement of biomass;

high/higher than optimum temperatures denature enzymes (of Calvin cycle); ribulose bisphosphate carboxylase/rubisco stops working/does not bind substrate; wilting / withering / loss of water / decrease in turgor / increased transpiration; closure/reduced aperture of stomata; lower CO 2  level inside leaf / reduced CO 2  diffusion/uptake into leaf;

rate decreases/drops (to zero) with drought  and  increases when re-watered/recovering

slight decrease/constant initially then falls / falls increasingly rapidly / decreases exponentially (in drought/up to Day 35); increases  almost to original level/ but doesn’t reach original level / rapidly at first then less rapidly / increases then reaches plateau (during recovery/after Day 35);

higher/greater (emission) at 35°C than 25°C during both drought and recovery; both at (approximately) same level at end of drought period/at 35 days; both increase during recovery but not to original level; less/little difference in emission between temperatures during recovery/after watering / converse;

decreases (rate of photosynthesis);

no effect before (the first) heat treatment; lower rate/greater reduction in rate during heat treatments with fosmidomycin; lower photosynthesis/fosmidomycin reduces recovery after heat treatments; Ignore statements that fosmidomycin reduces the rate of photosynthesis if this is not related to heat treatments.

high temperature/heat stress/treatment reduces rate of photosynthesis; repeated heat treatments cause greater reduction in photosynthesis; isoprene causes less change/less reduction in photosynthesis due to heat/46°C /higher rate of photosynthesis during heat treatment with isoprene (than without); isoprene helps photosynthesis to rise again after heat (treatments);

26 (%) ( Allow a range of 25 % to 27 % )

faster recovery with isoprene than without/than with water treatment; recovery faster/better/improved with higher isoprene concentration (than lower); after both time periods / after 24 hours and 1 hour;

different plants live in/evolved in/are adapted to different temperature regimes; (selective) advantage for plants that produce isoprene in high temperature regions; isoprene synthesis uses energy/materials/only beneficial at high temperatures; some plants do not have the enzymes/genes for making isoprene;

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Development of the idea

Overall reaction of photosynthesis.

• Basic products of photosynthesis
• Evolution of the process
• Light intensity and temperature
• Carbon dioxide
• Internal factors
• Energy efficiency of photosynthesis
• Structural features
• Light absorption and energy transfer
• The pathway of electrons
• Evidence of two light reactions
• Photosystems I and II
• Quantum requirements
• The process of photosynthesis: the conversion of light energy to ATP
• Elucidation of the carbon pathway
• Carboxylation
• Isomerization/condensation/dismutation
• Phosphorylation
• Regulation of the cycle
• Products of carbon reduction
• Photorespiration
• Carbon fixation in C 4 plants
• Carbon fixation via crassulacean acid metabolism (CAM)
• Differences in carbon fixation pathways
• The molecular biology of photosynthesis

Why is photosynthesis important?

What is the basic formula for photosynthesis, which organisms can photosynthesize.

photosynthesis

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• Khan Academy - Photosynthesis
• Biology LibreTexts - Photosynthesis
• University of Florida - Institute of Food and Agricultural Sciences - Photosynthesis
• Milne Library - Inanimate Life - Photosynthesis
• National Center for Biotechnology Information - Chloroplasts and Photosynthesis
• Roger Williams University Pressbooks - Introduction to Molecular and Cell Biology - Photosynthesis
• BCcampus Open Publishing - Concepts of Biology – 1st Canadian Edition - Overview of Photosynthesis
• photosynthesis - Children's Encyclopedia (Ages 8-11)
• photosynthesis - Student Encyclopedia (Ages 11 and up)
• Table Of Contents

Photosynthesis is critical for the existence of the vast majority of life on Earth. It is the way in which virtually all energy in the biosphere becomes available to living things. As primary producers, photosynthetic organisms form the base of Earth’s food webs and are consumed directly or indirectly by all higher life-forms. Additionally, almost all the oxygen in the atmosphere is due to the process of photosynthesis. If photosynthesis ceased, there would soon be little food or other organic matter on Earth, most organisms would disappear, and Earth’s atmosphere would eventually become nearly devoid of gaseous oxygen.

The process of photosynthesis is commonly written as: 6CO 2 + 6H 2 O → C 6 H 12 O 6 + 6O 2 . This means that the reactants, six carbon dioxide molecules and six water molecules, are converted by light energy captured by chlorophyll (implied by the arrow) into a sugar molecule and six oxygen molecules, the products. The sugar is used by the organism, and the oxygen is released as a by-product.

The ability to photosynthesize is found in both eukaryotic and prokaryotic organisms. The most well-known examples are plants, as all but a very few parasitic or mycoheterotrophic species contain chlorophyll and produce their own food. Algae are the other dominant group of eukaryotic photosynthetic organisms. All algae, which include massive kelps and microscopic diatoms , are important primary producers.  Cyanobacteria and certain sulfur bacteria are photosynthetic prokaryotes, in whom photosynthesis evolved. No animals are thought to be independently capable of photosynthesis, though the emerald green sea slug can temporarily incorporate algae chloroplasts in its body for food production.

photosynthesis , the process by which green plants and certain other organisms transform light energy into chemical energy . During photosynthesis in green plants, light energy is captured and used to convert water , carbon dioxide , and minerals into oxygen and energy-rich organic compounds .

It would be impossible to overestimate the importance of photosynthesis in the maintenance of life on Earth . If photosynthesis ceased, there would soon be little food or other organic matter on Earth. Most organisms would disappear, and in time Earth’s atmosphere would become nearly devoid of gaseous oxygen. The only organisms able to exist under such conditions would be the chemosynthetic bacteria , which can utilize the chemical energy of certain inorganic compounds and thus are not dependent on the conversion of light energy.

Energy produced by photosynthesis carried out by plants millions of years ago is responsible for the fossil fuels (i.e., coal , oil , and gas ) that power industrial society . In past ages, green plants and small organisms that fed on plants increased faster than they were consumed, and their remains were deposited in Earth’s crust by sedimentation and other geological processes. There, protected from oxidation , these organic remains were slowly converted to fossil fuels. These fuels not only provide much of the energy used in factories, homes, and transportation but also serve as the raw material for plastics and other synthetic products. Unfortunately, modern civilization is using up in a few centuries the excess of photosynthetic production accumulated over millions of years. Consequently, the carbon dioxide that has been removed from the air to make carbohydrates in photosynthesis over millions of years is being returned at an incredibly rapid rate. The carbon dioxide concentration in Earth’s atmosphere is rising the fastest it ever has in Earth’s history, and this phenomenon is expected to have major implications on Earth’s climate .

Requirements for food, materials, and energy in a world where human population is rapidly growing have created a need to increase both the amount of photosynthesis and the efficiency of converting photosynthetic output into products useful to people. One response to those needs—the so-called Green Revolution , begun in the mid-20th century—achieved enormous improvements in agricultural yield through the use of chemical fertilizers , pest and plant- disease control, plant breeding , and mechanized tilling, harvesting, and crop processing. This effort limited severe famines to a few areas of the world despite rapid population growth , but it did not eliminate widespread malnutrition . Moreover, beginning in the early 1990s, the rate at which yields of major crops increased began to decline. This was especially true for rice in Asia. Rising costs associated with sustaining high rates of agricultural production, which required ever-increasing inputs of fertilizers and pesticides and constant development of new plant varieties, also became problematic for farmers in many countries.

A second agricultural revolution , based on plant genetic engineering , was forecast to lead to increases in plant productivity and thereby partially alleviate malnutrition. Since the 1970s, molecular biologists have possessed the means to alter a plant’s genetic material (deoxyribonucleic acid, or DNA ) with the aim of achieving improvements in disease and drought resistance, product yield and quality, frost hardiness, and other desirable properties. However, such traits are inherently complex, and the process of making changes to crop plants through genetic engineering has turned out to be more complicated than anticipated. In the future such genetic engineering may result in improvements in the process of photosynthesis, but by the first decades of the 21st century, it had yet to demonstrate that it could dramatically increase crop yields.

Another intriguing area in the study of photosynthesis has been the discovery that certain animals are able to convert light energy into chemical energy. The emerald green sea slug ( Elysia chlorotica ), for example, acquires genes and chloroplasts from Vaucheria litorea , an alga it consumes, giving it a limited ability to produce chlorophyll . When enough chloroplasts are assimilated , the slug may forgo the ingestion of food. The pea aphid ( Acyrthosiphon pisum ) can harness light to manufacture the energy-rich compound adenosine triphosphate (ATP); this ability has been linked to the aphid’s manufacture of carotenoid pigments.

General characteristics

The study of photosynthesis began in 1771 with observations made by the English clergyman and scientist Joseph Priestley . Priestley had burned a candle in a closed container until the air within the container could no longer support combustion . He then placed a sprig of mint plant in the container and discovered that after several days the mint had produced some substance (later recognized as oxygen) that enabled the confined air to again support combustion. In 1779 the Dutch physician Jan Ingenhousz expanded upon Priestley’s work, showing that the plant had to be exposed to light if the combustible substance (i.e., oxygen) was to be restored. He also demonstrated that this process required the presence of the green tissues of the plant.

In 1782 it was demonstrated that the combustion-supporting gas (oxygen) was formed at the expense of another gas, or “fixed air,” which had been identified the year before as carbon dioxide. Gas-exchange experiments in 1804 showed that the gain in weight of a plant grown in a carefully weighed pot resulted from the uptake of carbon, which came entirely from absorbed carbon dioxide, and water taken up by plant roots; the balance is oxygen, released back to the atmosphere. Almost half a century passed before the concept of chemical energy had developed sufficiently to permit the discovery (in 1845) that light energy from the sun is stored as chemical energy in products formed during photosynthesis.

This equation is merely a summary statement, for the process of photosynthesis actually involves numerous reactions catalyzed by enzymes (organic catalysts ). These reactions occur in two stages: the “light” stage, consisting of photochemical (i.e., light-capturing) reactions; and the “dark” stage, comprising chemical reactions controlled by enzymes . During the first stage, the energy of light is absorbed and used to drive a series of electron transfers, resulting in the synthesis of ATP and the electron-donor-reduced nicotine adenine dinucleotide phosphate (NADPH). During the dark stage, the ATP and NADPH formed in the light-capturing reactions are used to reduce carbon dioxide to organic carbon compounds. This assimilation of inorganic carbon into organic compounds is called carbon fixation.

Van Niel’s proposal was important because the popular (but incorrect) theory had been that oxygen was removed from carbon dioxide (rather than hydrogen from water, releasing oxygen) and that carbon then combined with water to form carbohydrate (rather than the hydrogen from water combining with CO 2 to form CH 2 O).

By 1940 chemists were using heavy isotopes to follow the reactions of photosynthesis. Water marked with an isotope of oxygen ( 18 O) was used in early experiments. Plants that photosynthesized in the presence of water containing H 2 18 O produced oxygen gas containing 18 O; those that photosynthesized in the presence of normal water produced normal oxygen gas. These results provided definitive support for van Niel’s theory that the oxygen gas produced during photosynthesis is derived from water.

Home — Essay Samples — Science — Biology — Photosynthesis

Essays on Photosynthesis

Photosynthesis is a crucial process that occurs in plants, algae, and some bacteria, allowing them to convert light energy into chemical energy in the form of glucose. This process is essential for the survival of nearly all living organisms on Earth, as it provides the primary source of energy for the food chain and produces the oxygen we breathe. As such, photosynthesis is a fascinating and important topic for study and research. In this essay, we will explore a wide range of photosynthesis essay topics, providing a comprehensive resource for students and researchers interested in this vital biological process.

The Importance of the Topic

Understanding photosynthesis is crucial for numerous reasons. Firstly, it allows us to appreciate the incredible complexity and efficiency of the natural world. Photosynthesis is a fundamental process that underpins the entire ecosystem, and studying it can provide valuable insights into the interconnectedness of life on Earth. Furthermore, photosynthesis has significant implications for agriculture and food production, as well as for addressing environmental challenges such as climate change and air pollution. By delving into the various aspects of photosynthesis, researchers can uncover new ways to improve crop yields, develop sustainable energy sources, and mitigate the impacts of human activity on the environment.

Advice on Choosing a Topic

When selecting a photosynthesis essay topic, it is important to consider your specific interests and goals. There are countless facets of photosynthesis to explore, from the biochemical mechanisms of light capture and carbon fixation to the ecological and evolutionary implications of this process. If you are interested in biochemistry and molecular biology, you might choose a topic related to the enzymes and molecular structures involved in photosynthesis. Alternatively, if you are more intrigued by environmental science and ecology, you could explore the role of photosynthesis in ecosystems and its interactions with other biogeochemical cycles. Ultimately, the best topic for you will be one that aligns with your passions and allows you to make a meaningful contribution to the field of photosynthesis research.

Photosynthesis is a vast and multifaceted topic that offers numerous opportunities for study and exploration. Whether you are a student, a researcher, or simply someone with a curious mind, there is no shortage of intriguing photosynthesis essay topics to delve into. By delving into the various aspects of photosynthesis, researchers can uncover new ways to improve crop yields, develop sustainable energy sources, and mitigate the impacts of human activity on the environment.

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The Effect of Light Intensity on The Rate of Photosynthesis in Elodea (pondweed)

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Review of Types and Features of Cyanobacteria

Review of the abiotic and biotic factors and chemosynthesis process, review of the effects of nitrogen used as fertilizer, photosynthesis and cellular respiration, discussion on the fossil fuels and creation of algae into biofuels, the williamson ether synthesis: a cornerstone of organic chemistry, relevant topics.

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Important Questions on Plant Photosynthesis

In recent patterns of SSC, Banking, Railways, and others, we find important questions from the General Science section. In this section, Biology topics are considered important. In this article, we will provide a Practice set from one of the most important topics of Biology i.e Plant Photosynthesis. This practice will help students in revising the topic thoroughly.

List of Important Questions on Plant Photosynthesis :

Que 1. What happens when the process of photosynthesis takes place? (a) Taking oxygen and releasing carbon dioxide (b) Taking nitrogen and releasing oxygen (c) Taking oxygen and releasing nitrogen (d) Taking carbon dioxide and releasing oxygen

Ans. (d) Taking carbon dioxide and releasing oxygen Explanation: The process of photosynthesis involves taking carbon dioxide and releasing oxygen.  

Que 2. What gas played a major role in the process of photosynthesis? (a) Ammonia (b) Sulphur (c) Chlorine (d) Carbon dioxide

Ans. (d) Carbon dioxide Explanation: Carbon dioxide gas played a major role in the process of photosynthesis.  

Que 3. Which gas is released during the process of photosynthesis? (a) Carbon dioxide (b) Oxygen (c) Nitrogen (d) Hydrogen

Ans. (b) Oxygen Explanation: Oxygen gas is released during the process of photosynthesis.  

Que 4. Oxygen gas which is released during photosynthesis, comes from? (a) Water (b) Carbon dioxide (c) Ammonia (d) Chlorophyll

Ans. (a) Water Explanation: Oxygen gas which is released during photosynthesis, comes from water.  

Que 5. Which of the given lights are strongly absorbed by plants? (a) Indigo and Yellow (b) Yellow and Violet (c) Blue and Red (d) Orange and Violet

Ans. (c) Blue and Red Explanation: Blue and Red lights are strongly absorbed by plants because photosynthesis occurs more in these lights.  

Que 6. Which of the given options produces oxygen in a higher percentage? (a) Algae (b) Rice husks (c) Grasses (d) Trees

Ans. (a) Algae Explanation: Aquatic plants and Algae produces around 90% of oxygen.  

Que 7. Name the process by which plants synthesize their food. (a) Respiration (b) Photosynthesis (c) Osmosis (d) Reverse Osmosis

Ans. (b) Photosynthesis Explanation: Photosynthesis is the process by which plants synthesize their food.  

Que 8. The most effective light in the process of photosynthesis? (a) Violet (b) Green (c) Red  (d) Yellow

Ans. (c) Red  Explanation: The best photosynthesis takes place in the presence of the Red light spectrum.  

Que 9. During the process of photosynthesis, which of the following conversion takes place? (a) Chemical energy converted to electrical energy (b) Wind energy converted to chemical energy (c) Chemical energy converted to light energy (d) Light energy converted to chemical energy

Ans. (d) Light energy converted to chemical energy Explanation: During the process of photosynthesis, Light energy is converted to chemical energy.  

Que 10. Which of the following has the maximum efficiency in converting light energy to chemical energy? (a) Earthworm (b) Chlorella (c) Tiger (d) Snake

Ans. (b) Chlorella Explanation: Chlorella has the maximum efficiency in converting light energy to chemical energy.  

Que 11. Which of the following performs photosynthesis? (a) Green leaves of a plant (b) Roots of a plant (c) Seed of a plant (d) Stem of a plant

Ans. (a) Green leaves of a plant Explanation: Green leaves of a plant generally performs photosynthesis.  

Que 12. What function does Phloem perform? (a) Transportation of water (b)Transportation of food (c)Transportation of oxygen (d)Transportation of amino acid

Ans. (d) Transportation of food Explanation: Transportation of food is the main function of phloem.  

Que 13. What are the effects of deforestation? (a) Carbon dioxide levels will increase (b) Oxygen level will increase (c) Carbon dioxide levels will decrease (d) Pollution will decrease

Ans. (a) Carbon dioxide level will increase Explanation: Carbon dioxide levels will increase due to deforestation, which is very harmful to the life of organisms living on the earth.  

Que 14. Which of the given options has water-soluble photosynthetic pigments? (a) chlorophyll a (b) xanthophyll (c) Anthocyanin (d) chlorophyll b

Ans. (c) Anthocyanin Explanation: Anthocyanin has water-soluble photosynthetic pigments.  

Que 15. The minerals involved in the decomposition reactions during photosynthesis are? (a)manganese and chlorine (b)potassium and manganese (c)potassium and chlorine (d)magnesium and chlorine

Ans. (a) manganese and chlorine Explanation:   Manganese and chlorine are the minerals involved in the decomposition reactions during photosynthesis.  

Que 16. Where does the photoreaction occur? (a) Endoplasmic reticulum (b) Cytoplasm (c) Stroma (d) Grana

Ans. (d) Grana Explanation: Photoreaction occurs in grana. Grana is the stacks of thylakoids embedded in the stroma of a chloroplast.  

Que 17. Kranz’s anatomy can be seen in the leaves of? (a) wheat (b) sugarcane (c) potatoes (d) mustard

Ans. (b) sugarcane Explanation: Kranz’s anatomy can be seen in sugar cane leaves.  

Que 18. The most suitable temperature for photosynthesis is? (a) 35-40℃ (b) 25-35℃ (c)20-25℃ (d)10-15℃

Ans. (b) 25-35℃ Explanation: The most suitable temperature for photosynthesis is 25-35℃  

Que 19.  The process of photosynthesis takes place in? (a) Endoplasmic reticulum (b) Nucleus (c) Golgi body (d) Chloroplast

Ans. (d) Chloroplast Explanation:   The process of photosynthesis takes place in the Chloroplast.  

Que 20. Which among the following is the full form of ATP? (a) Adenosine Triphosphate (b) Amine Triphosphate (c) Ammonium Triphosphate (d) Amine Try Poly Phosphate

Ans. (a) Adenosine Triphosphate Explanation: The full form of ATP is Adenosine Triphosphate.

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