An antagonistic pair of muscles is made up of
A) two extensor muscles at the same joint.
B) two flexor muscles at the same joint.
C) an extensor muscle and a flexor muscle at the same joint.
D) two complex muscles that allow joints like hips and elbows to move in many directions.

Question

Quizplus · Accepted Answer

An antagonistic pair of muscles is made up of an extensor muscle and a flexor muscle at the same joint. One muscle contracts (the agonist), causing movement, while the other muscle relaxes (the antagonist). For example, the biceps and triceps muscles in the upper arm are an antagonistic pair. When the biceps muscle contracts, the arm bends at the elbow, and the triceps muscle relaxes. When the triceps muscle contracts, the arm straightens at the elbow, and the biceps muscle relaxes.

An Antagonistic Pair of Muscles Is Made Up of