All the following structure are found in an electrical synapse except

Options

A. Gap junction
B. Synaptic vesicles
C. Presynaptic membrane
D. Post - synaptic membrane

Answer

To solve the question, "All the following structures are found in an electrical synapse except," we need to analyze the options provided and understand the characteristics of electrical synapses.

### Step-by-Step Solution:

1. **Understand the Types of Synapses**:
- There are two main types of synapses: electrical and chemical.
- **Electrical Synapses**: These allow direct transmission of electrical signals between neurons through gap junctions.
- **Chemical Synapses**: These involve the release of neurotransmitters from synaptic vesicles to transmit signals.

2. **Analyze the Options**:
- **Gap Junction**: These are specialized intercellular connections that allow direct communication between adjacent neurons. They are indeed found in electrical synapses.
- **Synaptic Vesicles**: These are small membrane-bound structures that store neurotransmitters in chemical synapses. They are not present in electrical synapses.
- **Presynaptic Membrane**: This is the membrane of the neuron that releases neurotransmitters or electrical signals. It is present in electrical synapses.
- **Postsynaptic Membrane**: This is the membrane of the neuron that receives the signal. It is also present in electrical synapses.

3. **Identify the Incorrect Structure**:
- Since synaptic vesicles are associated with chemical synapses and not electrical synapses, they are the only structure listed that is not found in an electrical synapse.

4. **Conclusion**:
- The correct answer is **synaptic vesicles** (Option B).

### Final Answer:
**Option B: Synaptic Vesicles**