Neutral solutes can move across the membrane by the process of______.

Answer

**Step-by-Step Solution:**

1. **Understanding the Cell Membrane**: The cell membrane, also known as the plasma membrane, is semi-permeable or selectively permeable. This means it allows certain substances to pass through while restricting others.

2. **Types of Movement Across the Membrane**: There are two primary types of movement for solutes across the membrane:
- **Active Transport**: This process requires energy (ATP) because it moves substances against their concentration gradient (from low concentration to high concentration).
- **Passive Transport**: This process does not require energy and occurs along the concentration gradient (from high concentration to low concentration).

3. **Focusing on Neutral Solutes**: Neutral solutes are those that do not carry a charge. When discussing their movement across the membrane, we need to identify which type of transport they utilize.

4. **Identifying the Process for Neutral Solutes**: Neutral solutes typically move across the membrane via passive transport. Specifically, they do so through a process called **simple diffusion**. This means they move from an area of higher concentration to an area of lower concentration without the need for energy.

5. **Conclusion**: Therefore, the answer to the question is that neutral solutes can move across the membrane by the process of **simple diffusion**.

**Final Answer**: Neutral solutes can move across the membrane by the process of **simple diffusion**.

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