Concept explainers
The water necessary for photosynthesis
- is split into H2 and O2.
- is directly involved in the synthesis of carbohydrates.
- provides the elections to replace lost electrons in photosystem II.
- provides H+ needed to synthesize G3P.
- does none of the above.
Introduction:
The Calvin cycle utilizes the energy produced by the light-dependent reaction into synthesizing carbohydrates from carbon dioxide. The NADPH (nicotinamide adenine dinucleotide phosphate) acts as a reducing agent that adds the high energy electrons to the carbon dioxide molecule to form polysaccharide (glucose).
Answer to Problem 1TY
The correct answer is option (c) provides the electrons to replace lost electrons in photosystem II.
Explanation of Solution
Explanation/justification for the correct answer:
Option (c) provides the electrons to replace lost electrons in photosystem. Water does provide lost electrons for photosystem II that are used for the electron transport chain. So, the correct answer is option (c).
Explanation for incorrect answer:
Option (a) is split into H2 and O2. Splitting of water under the presence of light to yield hydrogen and oxygen is known as photolysis of water to provide electrons for the reaction. So, this is an incorrect option.
Option (b) is directly involved in the synthesis of carbohydrates. Water is no directly involved in the synthesis of carbohydrates as it provides electrons for reduction of NADH that participates in the production of carbohydrates. So, this is an incorrect option.
Option (d) provides H+ needed to synthesize G3P. The protons for the synthesis for G3P come from the photolysis of water, but that is not the necessary source of protons they can also come from thylakoid membrane. So, this is an incorrect answer.
Option (e) does none of the above. The water is necessary for the compensation of the electrons that are lost in the photosystem II and these electrons participate in the electron transport chain. So, this is an incorrect answer.
Water is required as a source of electrons in the light reaction where photosystems get activated and lead to an electron transport chain to produce energy-rich molecules. Hence, the correct answer is option (c) provides the electrons to replace lost electrons in photosystem II.
Want to see more full solutions like this?
Chapter 7 Solutions
Gen Combo Principles Of Biology; Connect Access Cards
- Figure 8.18 Which of the following statements is true? In photosynthesis, oxygen, carbon dioxide, ATP, and NADPH are reactants. G3P and water are products. In photosynthesis, chlorophyll, water, and carbon dioxide are reactants. G3P and oxygen are products. In photosynthesis, water, carbon dioxide, ATP, and NADPH are reactants. RuBP and oxygen are products. In photosynthesis, water and carbon dioxide are reactants. G3P and oxygen are products.arrow_forwardIs the following statement true or false? Unlike animals, which make many ATP by aerobic respiration, plants make all of their ATP by photosynthesis.arrow_forwardWhat is the molecule that leaves the Calvin cycle to be converted into glucose? a. ADP b. G3P c. RuBP d. 3-PGAarrow_forward
- Which of the following substances does not participate in the Calvin-Benson cycle? a. ATP c. NADPH e. PGAL b. O2 d. RuBP f. CO2arrow_forwardMatch each term with its most suitable description. ____ PGAL formation a. absorbs light ____CO2 fixation b. converts light to chemical energy ____ autotroph c. self-feeder ____ ATP forms NADPH does not d. electrons cycle back to photosystem ____ photorespiration e. problem in C3 plants ____ photosynthesis f. Calvin-Benson cycle product ____ pigment g. water molecules split ____ photolysis in photosynthesis h. rubisco functionarrow_forwardDuring photosynthesis, low energy electrons are struck by light, bumped up to higher energy levels, and then incorporated into organic molecules. Where does the chloroplast or Cyanobacterium obtain these electrons? From carbon dioxide From sunlight From water From ATParrow_forward
- Which of the following reactions produces the oxygen released by photosynthesis? chemiosmosis reduction of NADP+ splitting of water molecules electron transfer in photosystem Iarrow_forwardWhich of the following statements about photosynthesis is NOT true? Light independent reactions are very similar to the electron transport chain of cellular respiration Light is absolutely essential for both aspects of photosynthesis In order replace electrons, water is split to form oxygen gas Light dependent reactions are very similar, but in reverse, to the Krebs cycle and glycolysisarrow_forwardWhich of the following is produced during the light reactions of photosynthesis? C6H12O6 CO2 O2 ADParrow_forward
- Carbon fixation during the light-independent reaction of photosynthesis obtains its carbon atoms: from water molecules only from carbon monoxide molecules only from H2O molecules only from carbon dioxide molecules only from CO molecules onlyarrow_forwardWhich of the following are produced directly as a result of the movement of electrons through the photosynthetic electron transport chain carbohydrates and ATP ATP and NADPH O2 and carbohydrates H2O and carbohydratesarrow_forwardWhich of the following correctly describes the flow of electrons during photosynthesis? Select one: a. water, PS II, PS I, sugars b. glucose, water, O2, PSII c. water, sugars, PS I, PSII d. CO2, water, glucose, PSI e. water, PS I, PS II, sugarsarrow_forward
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College