Which term describes muscles that work to straighten a joint?

The term that describes muscles that work to straighten a joint is "extensor." Extensor muscles are responsible for increasing the angle between the segments of a joint, effectively allowing for the straightening movement. For example, when you extend your arm, the triceps muscle acts as an extensor by straightening the elbow joint.

The concept of extensors is fundamental in understanding how muscles facilitate movement in the body by working in pairs with flexors, which perform the opposite action of bending a joint. Knowing this distinction is crucial for studying muscular function in activities ranging from basic movements to complex athletic skills.