9. Photosynthesis

Describe the primary function of the light reactions of photosynthesis.

a) Production of NADPH used in cellular respiration.

b) Use of ATP to make glucose.

c) Conversion of chemical energy to light energy.

d) Production of ATP and NADPH.

Where do the electrons that are excited in photosystem II come from?

a) CO₂.

b) O₂.   

c) Glucose.   

d) Photosystem I.   

e) Water.

During the light reactions, photosystem I functions to_________, and photosystem II functions to __________.

a) Reduce CO₂; oxidize NADPH.

b) Synthesize ATP; Produce O₂.

c) Produce O₂; oxidize NADPH.

d) Reduce NADP⁺; oxidize H₂O.

What is the correct order of steps of the light reactions of Photosynthesis?

a) photosystem I, ETC, photosystem II, NADP⁺ reduction, chemiosmosis.

b) photosystem I, photosystem II, ETC, NADP⁺ reduction, chemiosmosis.

c) photosystem II, ETC, photosystem I, NADP⁺ reduction, chemiosmosis.

d) photosystem II, photosystem I, ETC, NADP⁺ reduction, chemiosmosis.

Which of the following sequences correctly represents the flow of electrons during photosynthesis? a. NADPH→O2→CO2 b. H2O→NADPH→Calvin cycle c. H2O→photosystem I→photosystem II d. NADPH→electron transport chain→O2

Which of the following does not occur during the light reactions of photosynthesis? a. Water is released; b. Electrons from chlorophyll are moved to a higher-energy state by light; c. ATP is produced; d. NADPH is produced to carry electrons to the light-independent reactions; e. Oxygen is produced when water is split.

In mechanism, photophosphorylation is most similar to a. substrate-level phosphorylation in glycolysis. b. oxidative phosphorylation in cellular respiration. c. carbon fixation. d. reduction of NADP+.

Which of the following is a false statement about photosynthesis? a. During the light-independent reactions, electrons and ATP from the light reactions combine with atmospheric carbon dioxide to produce sugars; b. The light-independent reactions take place in the chloroplast stroma; c. Oxygen produced during the light-independent reactions is released into the atmosphere; d. Chlorophyll absorbs blue and red light and reflects green light; e. The end product of photosynthesis is a carbohydrate such as glucose.

Which process is most directly driven by light energy? a. creation of a pH gradient by pumping protons across the thylakoid membrane b. reduction of NADP+ molecules c. transfer of energy from pigment molecule to pigment molecule d. ATP synthesis

Which of the following correctly identify a role of the ATP produced in the light-capturing reactions? Select True or False for each statement. T/F It is used by rubisco to fix CO2 to RuBP. T/F It serves the same role as ATP produced by mitochondria. T/F It is used to regenerate RuBP from G3P molecules. T/F It is used to produce G3P molecules

Predict how the following conditions would affect the production of O2, ATP, and NADPH and state whether noncyclic or cyclic electron flow would occur in each;(3) blue and red photons hit a chloroplast, but a proton channel has been introduced into the thylakoid membrane, so it is fully permeable to protons.

Predict how the following conditions would affect the production of O2, ATP, and NADPH and state whether noncyclic or cyclic electron flow would occur in each;(2) blue and red photons hit a chloroplast, but no NADP+ is available

Predict how the following conditions would affect the production of O2, ATP, and NADPH and state whether noncyclic or cyclic electron flow would occur in each: (1) Only blue photons hit a chloroplast

An investigator exposes chloroplasts to 700-nm photons and observes low O2 production, but high ATP production. Which of the following best explains this observation? a. The electrons from water are directly transferred to NADP+, which is used to generate ATP. b. Photosystem II is not splitting water, and the ATP is being produced by cycling electrons via photosystem I. c. The O2 is being converted to water as a terminal electron acceptor in the production of ATP. d. Electron transport has stopped and ATP is being produced by the Calvin cycle.