CH 10 HW

Which of the following molecules is the primary product of photosystem I? A.) NADPH B.) CO2 C.) ATP D.) Oxygen

A

Which of the following particles can pass through the ATP synthase channel? A.) ATP B.) Protons C.) Inorganic phosphate D.) ADP

B

Which process produces oxygen? A.) cellular respiration B.) photosynthesis

B

Which set of reactions uses H20 and produces O2? A.) light independent reactions B.) light dependent reactions

B

The electrons derived from this oxidation reaction in the Calvin cycle are used to reduce ______ to ______

CO2 to G3P

What are the inputs and outputs of the Calvin cycle?

Input: ATP, NADPH, CO2 Output: ADP, NADP+, G3P

What are the inputs and outputs of light reactions?

Inputs: light, water, ADP, NADP+ Outputs: O2, ATP, NADPH

How many electrons at a time are passed between the pigment molecules in the light-harvesting complexes?

0

If the Calvin cycle slows down, what will happen to the rate of O2 production in PS II, and why? A.) O2 production will slow down because less NADP+ will be regenerated in the Calvin cycle. B.) O2 production will speed up because not as much NADPH will be used in the Calvin cycle and so it will accumulate in the chloroplast. C.) O2 production will not change because light energy will still be absorbed by the pigment molecules and excite the PS II chlorophyll a pair. D.) O2 production will slow down because the chloroplast will need less light energy to send to the Calvin cycle. E.) O2 production will not change because the Calvin cycle is a separate process from the light reactions.

A

Which of the following are products of the light reactions of photosynthesis? A.) oxygen, ATP, and NADPH B.) water and CO2 C.) high-energy photons D.) NADP+ and RuBP E.) glyceraldehyde-3-phosphate

A

Which of the following is the correct order of electron flow in the light reactions of photosynthesis? A.) H2O → P680 chlorophyll a pair → PS II primary electron acceptor → Pq → cytochrome complex → Pc → P700 chlorophyll a pair → PS I primary electron acceptor → Fd → NADPH B.) H2O → P680 chlorophyll a pair → PS II primary electron acceptor → Pq → cytochrome complex → Pc → P700 chlorophyll a pair → PS I primary electron acceptor → Fd → ATP C.) H2O → P700 chlorophyll a pair → PS I primary electron acceptor → Pc → cytochrome complex → Pq → P680 chlorophyll a pair → PS II primary electron acceptor → Fd → NADPH D.) O2 → P680 chlorophyll a pair → PS I primary electron acceptor → Pq → cytochrome complex → Pc → P700 chlorophyll a pair → PS II primary electron acceptor → Fd → NADPH E.) H2O → P680 chlorophyll a pair → PS II primary electron acceptor → Pq → ATP → Pc → P700 chlorophyll a pair → PS I primary electron acceptor → Fd → NADPH

A

Chloroplast membrane vesicles are equilibrated in a simple solution of pH 5‎ . The solution is then adjusted to pH 8‎ . Which of the following conclusions can be drawn from these experimental conditions?

A.) ATP will be produced because the proton gradient favors proton movement through the ATP synthase channels. B.) ATP will not be produced because there is no ADP and inorganic phosphate in the solution. C.) The change in the solution's pH results in a gradient across the chloroplast membranes such that there is a lower concentration of protons inside the vesicles and a higher concentration outside. D.) Protons will not diffuse toward the outside of the vesicles.

What is important about the light-independent reactions in terms of carbon flow in the biosphere? A.) The light-independent reactions turn glucose, a sugar, into CO2 gas. B.) The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars. C.) The light-independent reactions use CO2 to make ATP. D.) The light-independent reactions turn sugar into ATP for energy.

B

Why is it correct to say that the linear electron flow of the light reactions directly captures energy in NADPH but only indirectly captures energy in ATP? A.) Electrons used to generate ATP are extracted from water, but electrons used to generate NADPH come directly from PS I B.) Electrons are directly transferred to NADP+ to form NADPH, but electron flow is used to generate a proton gradient for ATP synthesis. C.) Electrons are not directly transferred to ATP.Light energy is used to excite electrons used to generate NADPH, but the energy used to make ATP comes from the cytochrome complex. D.) Electrons are directly transferred to NADP+ to form NADPH in the electron transport chain after PS I, but ATP synthesis requires electrons that have flowed through both photosystems. E.) NADPH is generated directly in the chloroplast, but ATP is synthesized in the mitochondrion.

B

When a pigment molecule in a light-harvesting complex absorbs a photon of light, what happens to its excited-state electron? A.) The excited-state electron excites electrons in other pigments around it, so that multiple pigments can send electrons to P680 or P700 B.) .The excited-state electron is passed to electron acceptors P680 or P700. C.) The electron falls back to its ground state, while passing its excited-state energy to an electron in a nearby pigment molecule. D.) The excited-state electron is removed and transferred to a nearby pigment molecule, causing the next pigment to enter an excited state.

C

Photosynthetic membranes are found in the ________ in plant cells.

Chloroplasts

In C4 and CAM plants CO2 is fixed in the _______ of mesophyll cells.

Cytoplasm

Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis? A.)The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions. B.) The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions. C.) The light-independent reactions release energy, and the light-dependent reactions require energy. D.) The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.

D

T/F The chemiosmotic hypothesis states that the synthesis of ATP generates a proton gradient that leads to electron flow through an electron transport chain.

False

T/F The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.

False

In light reaction, light energy is used to oxidize_____ to ______

H2O to O2

The electrons derived from this oxidation reaction in the light reactions are used to reduce _____ to _____

NADP+ to NADPH

The Calvin cycle oxidizes the light-reactions product ___ to ____

NADPH to NADP+

Which term describes ATP production resulting from the capture of light energy by chlorophyll?

Photophosphorylation

According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?

Proton gradient

Which molecule is regenerated in the regeneration place of the Calvin cycle? Without regeneration of this molecule, the Calvin cycle would stop.

RuBP

C4 plants differ from C3 and CAM plants in that C4 plants ________

Transfer fixed CO2 to cells in which the Calvin cycle occurs

T/F? The light dependent reactions of photosynthesis use water and produce oxygen.

True

Photosynthesis is a redox reaction. This means that H2O is _____ during the light reactions and CO2 is ______ during the Calvin cycle.

oxidized; reduced

In C3 plants the conservation of water promotes _______?

photorespiration

When light strikes chlorophyll molecules, they lose electrons, which are ultimately replaced by _____.

splitting water

For ever y molecule of O2 that is released by photosystem II, ____ H2O molecules are needed, which together pass ______ electrons to the PS II reaction-center complex.

2, 4

What is the biological significance of the light-independent reactions of photosynthesis? A.) They convert CO2 to sugar B.) They generate ATP and NADPH C.) They convert ATP to sugar D.) They make Oxygen

A