Question

Ferredoxin is a component of the

• A. Hill reaction
• B. Photosystem I
• C. P680
• D. Photosystem II

Answer 1

The correct option is B

Photosystem I

The correct option B.

Explanation of the correct option:

1. One of two photosystems involved in the photosynthetic light responses of algae, plants, and cyanobacteria is photosystem I (PSI, also known as plastocyanin-ferredoxin oxidoreductase).
2. An essential membrane protein complex called photosystem I use light energy to catalyze the movement of electrons from plastocyanin to ferredoxin across the thylakoid membrane.
3. The moderate-energy hydrogen carrier NADPH is ultimately created using the electrons that Photosystem I transfers. In addition to producing a proton-motive force that is used to create ATP, Photosystem I absorbs photon energy.

Explanation of the incorrect options:

Option A:

1. As a part of photosynthesis, the Hill reaction is the light-driven transfer of electrons from water to Hill reagents in a direction opposite the chemical potential gradient. The reaction was discovered in 1937 by Robin Hill.
2. The Hill reaction occurs when a final electron acceptor is reduced by a water ion's hydrogen ion in the presence of light.
3. It causes oxygen to be produced. NADP⁺ serves as the organism's last electron acceptor. In isolated chloroplasts, the rate of Hill reactions can be determined.
4. Hill reagent is used in laboratories as a synthetic electron acceptor that changes color when it is reduced. The Hill reagent 2,6-dichlorophenolindophenol is an example of this (DCPIP).

Option C:

1. The photosystem II's reaction center chlorophyll, also known as the main electron donor, is highly reactive and excels at absorbing light with a wavelength of 680 nm.
2. A collection of pigments called Supplement P680 are excitonically connected, meaning when they absorb a photon, they behave as if they are a single molecule. Its name is derived from the wavelength (in nanometers) that it is most effective at collecting. The electromagnetic spectrum at 680 nm is relevant in this instance.

Option D:

1. The initial protein complex in the light-dependent processes of oxygenic photosynthesis is known as photosystem II (or water-plastoquinone oxidoreductase). It can be found in plants, algae, and cyanobacteria's thylakoid membrane.
2. Enzymes in the photosystem absorb light photons to energize electrons, which are subsequently moved via a range of coenzymes and cofactors to convert plastoquinone to plastoquinol. By oxidizing water to produce hydrogen ions and molecular oxygen, the energetic electrons are swapped out for new ones.
3. Photosystem II provides the electrons necessary for the entire photosynthesis process by replacing lost electrons with electrons obtained from the splitting of water.
4. The hydrogen ions (protons) produced when water is oxidized contribute to the formation of a proton gradient that ATP synthase uses to produce ATP.

Final answer: Ferredoxin is the component of Photosystem I.