[Campbell Biology P.1181] Refer to Figure 50.35 showing human forearm movement. When the arm ... | Practice Question
Refer to Figure 50.35 showing human forearm movement. When the arm flexes bends at the elbow , the biceps muscle contracts. According to the principle of antagonistic muscle pairs illustrated, what is the state of the triceps muscle during this flexion?
Explanation
The text explains that for movement, muscles work in antagonistic pairs. When the biceps contracts for flexion, the triceps its antagonist must relax to allow the movement. This is visually represented in Figure 50.35, where the contracting muscle is blue and the relaxing muscle is green.