Antagonistic Muscles

What is Antagonistic Muscles?

A pair of muscles that produce opposite effects, so that when one contracts the other relaxes. The circular and radial muscles of the iris are an antagonistic pair: contraction of the circular muscles makes the pupil smaller, and contraction of the radial muscles makes it larger.

This definition is part of the Coordination and Control chapter in Cambridge O Level Biology.

Concepts related to Antagonistic Muscles

• circular muscle
• radial muscle