ATP in non-cyclic photophosphorlyation is formed when electron passes from

Options

A. plastocyanin to `P_(700)`
B. plastoquinone to ferrodoxin
C. cytochrome ƒ to plastoquinone
D. cytochrome b to cytochrome ƒ

Answer

To solve the question regarding the formation of ATP in non-cyclic photophosphorylation, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Non-Cyclic Photophosphorylation**:
- Non-cyclic photophosphorylation is a process that occurs in the thylakoid membranes of chloroplasts where light energy is converted into chemical energy in the form of ATP and NADPH. This process involves both Photosystem I (PSI) and Photosystem II (PSII).

2. **Electron Flow in Non-Cyclic Photophosphorylation**:
- In this process, electrons are excited by light energy absorbed by chlorophyll in PSII and are then transferred through a series of proteins in the electron transport chain.

3. **Key Components of the Electron Transport Chain**:
- The main components involved in the electron transport chain include plastoquinone, cytochrome b6f complex (which includes cytochrome b and cytochrome f), plastocyanin, and ferredoxin.

4. **Formation of ATP**:
- ATP is generated through the process of chemiosmosis, where the flow of electrons through the electron transport chain creates a proton gradient across the thylakoid membrane. The protons flow back into the stroma through ATP synthase, leading to the phosphorylation of ADP to form ATP.

5. **Identifying the Correct Electron Transfer**:
- The question asks specifically about the transfer of electrons that leads to ATP formation. The correct sequence of electron transfer that results in ATP synthesis is from cytochrome b to cytochrome f.

6. **Conclusion**:
- Therefore, the correct answer to the question is that ATP in non-cyclic photophosphorylation is formed when electrons pass from **cytochrome b to cytochrome f**.

### Final Answer:
- The correct option is: **cytochrome b to cytochrome f**.