Why are chemical messengers needed for transmission of a nerve signal at a synapse?
Answer and explanation
Correct answer: Because there is a small gap between two neurons
The governing concept is synaptic transmission. Neurons at a synapse are separated by a microscopic gap, so the electrical impulse cannot simply pass through continuous cytoplasm. When the impulse reaches the axon terminal, it triggers release of neurotransmitter chemicals; these diffuse across the synaptic cleft and stimulate the next neuron. Thus option A gives the necessary reason. The other choices assign impossible functions to the axon, dendrite or spinal cord.
Frequently asked questions
What is the correct answer to this question?
Because there is a small gap between two neurons
Why is this the correct answer?
The governing concept is synaptic transmission. Neurons at a synapse are separated by a microscopic gap, so the electrical impulse cannot simply pass through continuous cytoplasm. When the impulse reaches the axon terminal, it triggers release of neurotransmitter chemicals; these diffuse across the synaptic cleft and stimulate the next neuron. Thus option A gives the necessary reason. The other choices assign impossible functions to the axon, dendrite or spinal cord.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: World of Living. Topic: Control and Coordination.
