Which of the following features distinguishes all hormones from neurotransmitters?
A)Hormones require large concentrations to have an effect,while neurotransmitters require only low concentrations.
B)A hormone affects reproductive functions,while neurotransmitters control all other processes.
C)Hormones travel via the blood to a target tissue,while neurotransmitters cross the synaptic cleft to a postsynaptic cell.
D)Hormones are steroids,while neurotransmitters are amino acids.

Question

Quizplus · Accepted Answer

Hormones travel through the bloodstream to reach and affect target tissues, whereas neurotransmitters cross the synaptic cleft between neurons to affect a postsynaptic cell. This is the key distinguishing feature between hormones and neurotransmitters. Option A is incorrect because the concentration required for an effect varies for both hormones and neurotransmitters and cannot be used to distinguish between them. Option B is incorrect because some hormones also affect non-reproductive processes in the body, such as growth hormone and insulin. Option D is incorrect because while some hormones are steroids, others are peptides or amino acid derivatives, and neurotransmitters are primarily amino acids, but also include some peptides and gases.

Which of the Following Features Distinguishes All Hormones from Neurotransmitters