Question

Select the incorrect statement regarding synapses:

• A. The membranes of presynaptic and postsynaptic neurons are in close proximity in an electrical synapse.
• B. Electrical current can flow directly from one neuron into the other across the electrical synapse.
• C. Chemical synapse use neurotransmitters
• D. Impulse transmission across a chemical synapse is always faster than that across an electrical synapse

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
A synapse is a junction between two neurons. There are two types: Electrical and Chemical.
Detailed Explanation:
- (1) Correct: In electrical synapses, the gap between neurons is very small (close proximity), and they are connected by gap junctions.
- (2) Correct: Because of the direct connection, electrical current (ions) can flow directly from one cell to the next.
- (3) Correct: Chemical synapses use chemical messengers called neurotransmitters to bridge the synaptic cleft.
- (4) Incorrect: Transmission across an electrical synapse is always faster than across a chemical synapse because it doesn't involve the slow steps of neurotransmitter release, diffusion, and binding.
Step 2: Final Answer:
Statement (4) is false as it reverses the speed relationship between the two types of synapses.