Which bone lies on the opposite side of the forearm from the radius?

Which bone lies on the opposite side of the forearm from the radius?

• A. Ulna
• B. Radius
• C. Scapula
• D. Clavicle

Answer: (A)

Two bones form the forearm: the radius and the ulna. In the standard anatomical position, the radius is on the lateral (thumb) side, and the ulna is on the medial (pinky) side. So, the bone lying on the opposite side of the forearm from the radius is the ulna. The radius and ulna are connected by a fold called the interosseous membrane and can rotate relative to each other during forearm movements like pronation and supination. The other options are shoulder-related bones (scapula and clavicle) or the same bone (radius), so they don’t fit.

Two bones form the forearm: the radius and the ulna. In the standard anatomical position, the radius is on the lateral (thumb) side, and the ulna is on the medial (pinky) side. So, the bone lying on the opposite side of the forearm from the radius is the ulna. The radius and ulna are connected by a fold called the interosseous membrane and can rotate relative to each other during forearm movements like pronation and supination. The other options are shoulder-related bones (scapula and clavicle) or the same bone (radius), so they don’t fit.