Which statement about the membrane channel is not true?

Options

A. They are proteins
B. Movement through them is along the concentration gradient
C. The are pores in the membrane
D. All ions pass through the same type of channel

Answer

To determine which statement about membrane channels is not true, we can analyze each statement one by one:

1. **Membrane channels are specific intrinsic proteins.**
- This statement is true. Membrane channels are indeed specific proteins embedded within the membrane that facilitate the movement of ions and molecules.

2. **The movement through them is along a concentration gradient.**
- This statement is also true. The movement through membrane channels typically occurs via facilitated diffusion, which is a passive process that allows substances to move from an area of higher concentration to an area of lower concentration.

3. **The pores in the membrane are present.**
- This statement is true as well. Membrane channels create pores that allow specific ions and molecules to pass through the membrane.

4. **All ions pass through the same type of channel.**
- This statement is not true. Different ions require specific types of channels for transport. Each type of ion has a dedicated channel that is selective for that ion, meaning not all ions can pass through the same channel.

**Conclusion:**
The statement that is not true is: "All ions pass through the same type of channel."

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