WAEC - Biology (2005 - No. 19)
Which of the following statements is true about movement of the forearm? In
bending the arm, the biceps relax and the triceps contract
bending the arm, the biceps contract and the triceps relax
straightening the arm the biceps contract and the triceps relax
straightening the arm, both biceps and triceps contract
説明
To bend the arm, the biceps contracts and pulls on the radius. Simultaneously, the triceps relaxes.