Simple diffusion means_______

Answer

**Step-by-Step Text Solution:**

1. **Definition of Simple Diffusion**: Simple diffusion is a process that involves the movement of particles from an area of higher concentration to an area of lower concentration.

2. **No Membrane Requirement**: In simple diffusion, there is no need for a biological membrane to facilitate the movement of particles. This distinguishes it from other forms of transport that may require a membrane.

3. **Direction of Movement**: The movement of substances during simple diffusion occurs downhill, meaning it naturally flows from areas where they are more concentrated to areas where they are less concentrated.

4. **No Facilitators Needed**: Simple diffusion does not require any facilitators or transport proteins to assist in the movement of particles. It is a passive process.

5. **Example of Simple Diffusion**: A common example of simple diffusion is when perfume is sprayed in one corner of a room. The fragrance molecules move from the area of high concentration (where the perfume was sprayed) to areas of lower concentration throughout the room, illustrating how simple diffusion works.

**Final Answer**: Simple diffusion means the movement of particles from an area of high concentration to an area of low concentration without the need for a membrane or any facilitators.

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