Answer:
B. A proton gradient drives the formation of ATP from ADP and inorganic phosphate via ATP synthase.
Explanation:
Light reaction of photosynthesis includes the splitting of water in the presence of sunlight and electron transfer from PSII to PSI via an electron transport system. During the transfer of electron through cytochrome of the electron transport system, the proton concentration gradient is generated across thylakoids. The proton concentration gradient is harvested to drive ADP phosphorylation by the catalytic site of ATP synthase accompanied by downhill movement protons through its proton channels.
Answer:
All of the above is correct
Explanation:
<span>Unidirectional flow in the heart is ensured because the heart contains valves that prevent backflow.
These valves keep the flow of the heart going in one direction (hence the name "unidirectional").</span>
If a plant cell had a mutation such that the cyclic electron flow is observed at a much higher rate, which photosystem is most likely mutated such that energy is absorbed at a lower rate?
PSI
PSII
Answer:
PSII
Explanation:
Non-cyclic phosphorylation involves both PSI and PSII. The process starts with the splitting of water and excitation of electrons of the reaction center of PSII upon the absorption of solar energy at the wavelength of 680 nm. Any mutation in PSII would not allow the non-cyclic phosphorylation to occur when only cyclic phosphorylation would occur. The process of cyclic phosphorylation includes only PS I. Its reaction center absorbs maximum light at 700 nm and is cycled back while supporting ATP synthesis. Therefore, if a plant performs cyclic phosphorylation at a higher rate and absorbs less energy, this means that mutation was in PSII.
