Question

Neurotransmitters are defined by four essential characteristics. These are:

	A.	Neurotransmitters are synthesized within presynaptic neurons.
	B.	Depolarization of a neuron results in the release of a neurotransmitter, which exerts a multitude of actions on the postsynaptic neuron.
	C.	Their action on postsynaptic neurons can be replicated by administering a drug that mimics the activity of the endogenous neurotransmitter.
	D.	Their action in the synaptic cleft is terminated by a specific action.
	E.	A, C, and D only

Answer 1

AnsOption E} A,C and D only. is correct option

Neurotransmitters- Neurotransmitters are chemical messengers in the body that transmit a message from a nerve cell across the synapse to a target cell.

Option A is correct for neurotransmitter because Neurotransmitters are synthesized in neurons and are stored in the presynaptic terminal

Option B) is incorrect because depolarization does not directly release neurotransmitter when depolarization reaches the nerve synapse only then neurotransmitters are released. Depolarization occurs when a stimulus reaches a resting neuron and the cells undergo a change in membrane potential Depolarization of neuron generates a strong nerve impulse that travels along the entire length of neuron up to the synaptic terminal(via sodium potassium channel) for  release of neurotransmitters. So depolarization is a channel of flow which lead to release of neurotranmitter

Option C is correct it is an important criteria or chracterstic of a neurotranmitter- when the chemical or drug that mimic the activity of the endogenous neurotransmitter is experimentally placed in site we get the same response on postsynaptic neuron

Option D this option is also correct as characterstic feature of neurotransmitter- as there is always a mechanism to remove the neurotranmitter from the site of activation after its action is being achieved.