Question

2 which of the following muscles extends the forearm at the elbow joint?
a. brachioradialis m.
b. triceps brachii m.
c. biceps brachii m.
d. brachialis m.
3 circle all that apply. which of the following muscles flex the forearm at the elbow joint?
a. flexor digitorum superficialis m.
b. triceps brachii m.
c. brachioradialis m.
d. brachialis m.
e. flexor hallucis longus m.
f. biceps brachii m.
4 which of the following muscles flexes the thigh at the hip?
a. iliopsoas m.
b. biceps femoris m.
c. vastus intermedius m.
d. gluteus medius m.

Explanation:

• Question 2:
• The triceps brachii muscle is the primary extensor of the forearm at the elbow joint. The brachioradialis is a flexor and also assists in supination/pronation. The biceps brachii is a flexor and supinator. The brachialis is a flexor.
• Question 3:
• The brachioradialis, brachialis, and biceps brachii are major flexors of the forearm at the elbow. The flexor digitorum superficialis flexes the fingers. The triceps brachii extends the forearm. The flexor hallucis longus is a foot muscle (flexes the big toe).
• Question 4:
• The iliopsoas is a major hip flexor. The biceps femoris is a hamstring (extends hip, flexes knee). The vastus intermedius is a quadriceps (extends knee). The gluteus medius is a hip abductor.

Answer:

• Question 2: B. Triceps brachii m.
• Question 3: C. Brachioradialis m., D. Brachialis m., F. Biceps brachii m.
• Question 4: A. Iliopsoas m.