Question

In a synapse, a chemical signal is transmitted from

• A. Dendritic end of one neuron to axonal end of another neuron
• B. Axon to the cell body of the same neuron
• C. Cell body to the axonal end of the same neuron
• D. Axonal end of one neuron to the dendritic end of another neuron

Answer 1

The correct option is D

Axonal end of one neuron to the dendritic end of another neuron

The correct option is D.

Explanation for the correct option:

Option D:

1. Information is passed from one neuron to the next at synapses, the points of contact between neurons.
2. Presynaptic neurons, synaptic cleft, and postsynaptic neurons are the components of synapses, which most frequently develop between axons and dendrites.
3. The presynaptic neuron in a synapse "converted" an electrical signal into a neurotransmitter, which then diffused (swam) over the synaptic cleft until it reached the other neuron.
4. Thus, the signal moves from the dendritic end of one neuron to the axonal end of the following neuron.
5. Between presynaptic and postsynaptic neurons, the synapse is created.
6. The connection between a neuron and a muscle is called the neuromuscular junction.
7. Nerve impulses are sent from one neuron's axon terminal to the following neuron's dendrites via a synapse.
8. It might be chemical or electrical.

Explanations for the incorrect options:

Option A:

1. The point where one neuron's axon and another's dendrite converge, allowing two neurons to communicate.
2. There are several dendritic terminals that receive signals from other neurons or sensory organs, transmit them to the cell body, and then carry those impulses along the axonal membrane.

Option B:

1. Neurotransmitters are not released by axons to their own cell bodies.
2. Neurotransmitter receptors and neurotransmitter release are not present in the cell bodies themselves.
3. They do carry the signal through the membrane by gradually depolarizing and repolarizing it.

Option C:

1. The axon guides the signal to a specific neuron or group of neurons.

Final answer: In a synapse, a chemical signal is transmitted from the axonal end of one neuron to the dendritic end of another neuron.