Select the incorrect statement for single ion channel :

Options

A. Transport porteins
B. Rapid change in shape
C. Gated channels
D. Movement across membranes

Answer

To solve the question regarding which statement about single ion channels is incorrect, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which of the four statements about single ion channels is incorrect.

2. **Analyze Each Statement**:
- **Statement 1**: "Transport proteins."
- This statement suggests that single ion channels transport proteins. However, single ion channels primarily facilitate the movement of ions, not proteins. Therefore, this statement is **incorrect**.

- **Statement 2**: "Rapid change in shape."
- This statement indicates that there is a rapid change in shape when ions enter or exit the channel. This is true for many ion channels, as they can undergo conformational changes during ion transport. Thus, this statement is **correct**.

- **Statement 3**: "Gated channels."
- This statement suggests that single ion channels are gated channels that allow selective entry and exit of ions. This is also true, as many ion channels are gated and regulate ion flow. Therefore, this statement is **correct**.

- **Statement 4**: "Movement across membranes."
- This statement implies that single ion channels facilitate movement across membranes. While this is generally true, the phrasing can be misleading. Single ion channels do allow ions to move across membranes, but they do not transport proteins. However, the context of the question requires us to focus on the incorrectness of the first statement primarily.

3. **Identify the Incorrect Statement**:
- Based on the analysis, the first statement about transporting proteins is the incorrect one regarding single ion channels.

### Conclusion:
The incorrect statement regarding single ion channels is **Statement 1: "Transport proteins."**

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