BIOCHEM, PHOTOSYNTHESIS

Which ONE has the greatest need for an electron? P680+ in its ground state. P680+ in its excited state. P700+ in its ground state. P700+ in its excited state.

P680+ in its ground state.

Which ONE has the lowest need for an electron? P700+ in its excited state. P680+ in its ground state. P680+ in its excited state. P700+ in its ground state.

P700+ in its excited state.

Which ONE of the following statements is INCORRECT? Photosynthesis in plants occurs in two stages. The first uses water to reduce CO2 to carbohydrates. The second uses NADPH to convert ADP into ATP. Some organisms use hydrogen gas instead of water as a reducing agent. The so-called "dark-reactions" are accelerated by light. Both atoms of oxygen in the O2 produced by photosynthesis come from water.

Photosynthesis in plants occurs in two stages. The first uses water to reduce CO2 to carbohydrates. The second uses NADPH to convert ADP into ATP.

Which ONE of the following is NOT a pair of molecules that have analogous functions in mitochondria and chloroplasts? Q cycle and light. Cytochrome c and plastocyanin. CF1 and F1. Plastoquinone and ubiquinone.

Q cycle and light.

Which ONE of the following describes how energy is transferred from antenna molecules to chlorphyll in the reaction center? Resonance transfer. Electron transfer. Breaking a chemical bond and forming a new one. Emission of fluorescence that is absorbed by the chlorophyll in the reaction center.

Resonance transfer.

Which ONE of the following statements about protons and photosynthesis is correct? The process of electron transport causes release of protons into the thylakoid lumen. The process of electron transport causes release of protons into the stroma. The process of electron transport causes translocation of protons out of the chloroplast across the chloroplast inner and outer membrane into the cytoplasm of the cell. The process of electron transport does not cause translocation of protons.

The process of electron transport causes release of protons into the thylakoid lumen.

As described in section 15.3 of the textbook the quantum efficiency for photosynthesis decreases abruptly when the wavelength of light being used becomes longer the 680 nm. Which ONE of the following is the explanation for this "red drop"? The reactions that extract electrons from water to make O2 take place in the photosystem that is activated by 680 nm light. Red light inhibits photosynthesis. Photosystem I requires 680 nm light Red light is absorbed CO2 to initate the synthesis of carbohydrates.

The reactions that extract electrons from water to make O2 take place in the photosystem that is activated by 680 nm light.

Which ONE is the part of a chloroplast that absorbs the light used to power photosynthesis? Thylakoid membrane. Chloroplast outer membrane. Chloroplast inner membrane. Stroma.

Thylakoid membrane.