Muscles Work in Pairs

Question 1

Which statement best describes what happens to the biceps and triceps when the arm is bent and then straightened?

Accepted Answer

When the arm bends, the biceps contract while the triceps relax; when the arm straightens, the triceps contract while the biceps relax.

Answer

Both the biceps and triceps contract together when the arm bends, and both relax when the arm straightens.

Answer

The biceps push the forearm upward when the arm straightens, while the triceps pull it downward.

Answer

The triceps relax when the arm bends and also relax when the arm straightens, leaving the biceps to do all the work.

Question 2

When you bend your elbow at the elbow joint, what happens to the biceps and triceps muscles?

Accepted Answer

The biceps contract and the triceps relax.

Answer

Both the biceps and triceps relax.

Answer

The biceps relax and the triceps contract.

Answer

Both the biceps and triceps contract.

Question 3

Which pair of muscles works as antagonists to bend and straighten the forearm at the elbow?

Accepted Answer

biceps brachii and triceps brachii

Answer

biceps brachii and brachialis

Answer

quadriceps femoris and hamstrings

Answer

triceps brachii and deltoid

Try three questions