function of nuclear pores is ..............

Options

A. Through these pores movement of RNA and protein molecules in both directions between the nucleus and the cytoplasm is performed
B. Transport of RNA in both direction between the Nucleus and the cytoplasm is performed
C. Only for transport of RNA in unidirectional manner from nucleus to cytoplasm
D. 1 and 3 option is correct

Answer

### Step-by-Step Solution:

1. **Understanding Nuclear Pores**: Nuclear pores are small openings in the nuclear membrane, which is the barrier surrounding the nucleus of a cell. They are formed by the fusion of the inner and outer membranes of the nucleus.

2. **Function of Nuclear Pores**: The primary function of nuclear pores is to regulate the movement of molecules between the nucleus and the cytoplasm. This includes the transport of RNA and proteins.

3. **Bidirectional Transport**: Nuclear pores allow for the movement of RNA and proteins in both directions—meaning that RNA can exit the nucleus to the cytoplasm, and proteins can enter the nucleus from the cytoplasm.

4. **Evaluating Options**:
- The first option states that nuclear pores facilitate the movement of RNA and protein molecules in both directions. This is correct.
- The second option mentions only the transport of RNA in both directions, which is partially correct but incomplete.
- The third option states that transport is unidirectional (only from nucleus to cytoplasm), which is incorrect.
- The last option combines the first and third options, which is also incorrect since the third option is wrong.

5. **Conclusion**: Based on the functions of nuclear pores, the correct answer is that they allow the movement of RNA and protein molecules in both directions between the nucleus and the cytoplasm.

### Final Answer:
The function of nuclear pores is to facilitate the movement of RNA and protein molecules in both directions between the nucleus and cytoplasm.

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