Agonist is to antagonist as: neuromodulator is to neurotransmitter. reuptake is to receptor. mimic is to block. block is to mimic.

The right answer is C. mimic is to block.

Agonist qualifies an effect that goes in the same direction.

Antagonist qualifies an effect that goes in the opposite direction.

For example

, the movements of the foot depend on two types of muscles - the flexors and the extensors - which cause opposite movements of the foot: flexion or extension. They are antagonistic muscles.

In pharmacology, these notions are very developed:

Agonists activate the receptors to induce the desired response. Conventional agonists increase the proportion of activated receptors. Many neurotransmitters (eg, acetylcholine, histamine, norepinephrine), drugs (eg, morphine, phenylephrine and isoproterenol, benzodiazepines, barbiturates) and hormones have agonist activity.

Antagonists prevent activation of the receptor. Blocking the activation of a receiver has many effects. Cell function will decrease if they block the action of a substance that normally increases cellular function.

the correct answer is anaphylaxis.

anaphylaxis is a condition caused by insect bites, foods, medications, manifested by tongue swelling, shortness of breath, vomiting, low blood pressure. it sometimes may occur without an obvious reason. it is treated with epinephrine injection.other tretments include antihistamines and steroids,