Question

Epinephrine and norepinephrine that are released from the adrenal glands affect target tissue for a longer period of time than the same substances released from neurons at their peripheral receptors. Why?

A) The adrenal gland releases larger amounts of the neurotransmitters than the neurons.
B) The hormones released from the adrenal glands bind to different receptors than those released from neurons.
C) There are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.
D) The effectors are less sensitive to epinephrine and norepinephrine released by the adrenal glands.
E) The epinephrine and norepinephrine from the adrenal glands are released by sympathetic neurons, whereas parasympathetic neurons release these substances at the effector organs.

Answer 1

• Option- C

Step-by-step explanation:

• Epinephrine and norepinephrine that are released from the adrenal glands affect target tissue for a longer period of time than the same substances released from neurons at their peripheral receptors.As there are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.

Answer 2

C) There are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.

Step-by-step explanation:

Epinephrine and norepinephrine are released from the adrenal gland ( adrenal medulla ) and neurons (adrenergic nerve endings) in the sympathetic nervous system. Epinephrine is a hormone while norepinephrine is a neurotransmitter.

As epinephrine and norepinephrine are released from the neurons , they act at their peripheral receptors and are cleaved by the enzymes in the liver and other tissues.Epinephrine and norepinephrine that are released from the adrenal glands affect target tissue for a longer period of time than the same substances released from neurons at their peripheral receptors because there are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.