Question

question 56
a muscle or group of muscles opposing the action is called an ______.

Explanation:

In anatomy (a subfield of Biology, which is part of Natural Science), a muscle or group of muscles that opposes the action of another muscle (the agonist) is defined as an antagonist. This term is used to describe the functional relationship between muscles in movement, where the antagonist relaxes or contracts to control the movement initiated by the agonist.

Answer:

antagonist