Which of the following is not the type of facilitated diffusion?

Options

A. Symport
B. Uniport
C. Antiport
D. apoport

Answer

To solve the question "Which of the following is not the type of facilitated diffusion?", we can follow these steps:

### Step 1: Understand Facilitated Diffusion
Facilitated diffusion is a process that allows substances to cross membranes with the assistance of special proteins. It occurs down the concentration gradient (from high to low concentration) and does not require energy (ATP).

**Hint:** Remember that facilitated diffusion involves carrier proteins and does not require energy.

### Step 2: Identify Types of Facilitated Diffusion
There are three main types of facilitated diffusion:
1. **Symport**: Both substances move in the same direction across the membrane.
2. **Antiport**: Substances move in opposite directions across the membrane.
3. **Uniport**: A single substance is transported across the membrane.

**Hint:** Think about how substances move in relation to each other in symport, antiport, and uniport.

### Step 3: Analyze the Options
The question provides several options, and we need to identify which one is not a type of facilitated diffusion. The options typically include terms related to transport mechanisms.

**Hint:** Look for terms that do not correspond to the types of facilitated diffusion mentioned.

### Step 4: Identify the Incorrect Option
From the analysis, "apoport" is mentioned in the video transcript as not being a recognized mechanism associated with facilitated diffusion. Therefore, it is the correct answer to the question.

**Hint:** If you see a term that doesn't match the known types of facilitated diffusion, it's likely the answer.

### Step 5: Conclusion
The correct answer to the question is the option that includes "apoport," as it is not a type of facilitated diffusion.

**Final Answer:** The option that is not a type of facilitated diffusion is "apoport."