Choose the false option -

Options

A. Flow of electrons in ETS is `Fe^(+3)rarrFe^(+2)rarrFe^(+3)`
B. In ETS electrones move from high negative to high positive redox potential
C. C y t `a_(3)` has Fe and Cu
D. Cytochrome are non-proteinaceous but ubiquinona is proteinaceous

Answer

To determine the false option from the given statements regarding the electron transport system (ETS) in respiration, let's analyze each option step by step.

1. **Option 1**: "Flow the electron in ETS, here Fe3+, Fe2+, Fe3+..."
- This statement discusses the flow of electrons in the electron transport system (ETS) and mentions the oxidation states of iron (Fe3+ and Fe2+). The flow of electrons does involve the reduction and oxidation of iron complexes, which is a correct description of the process.

2. **Option 2**: "ETS electrons move from high negative to high positive redox potential."
- This statement is incorrect. In the electron transport chain, electrons move from a high positive redox potential to a low negative redox potential. Therefore, this statement is false.

3. **Option 3**: "ETS electrons move from high positive to high negative."
- This statement is correct. It accurately describes the direction of electron flow in the ETS, which is from high positive redox potential to low negative redox potential.

4. **Option 4**: "Cytochrome A3 has iron as well as copper."
- This statement is partially correct. Cytochrome A3 primarily contains iron, and while it may have copper in some contexts, the main characteristic is its iron content. However, the statement is generally accepted as true in the context of cytochromes.

5. **Option 5**: "Cytochrome are non-proteinous."
- This statement is false. Cytochromes are indeed protein complexes that contain heme groups, which are essential for their function in the electron transport chain. Therefore, this statement is also false.

**Conclusion**: The false options are **Option 2** and **Option 5**. However, since we are asked to choose one, **Option 2** is the most directly incorrect regarding the flow of electrons in the ETS.