What is the long bone in the upper arm?

What is the long bone in the upper arm?

• A. Phalanges
• B. Carpals
• C. Metacarpals
• D. Humerus

Answer: (D)

The long bone in the upper arm is the humerus. It runs from the shoulder to the elbow, acting as the main lever for arm movement. Its proximal end forms a joint with the scapula at the shoulder, and its distal end forms the elbow joint with the forearm bones. The humerus is characterized by a long shaft (diaphysis) and rounded ends (epiphyses) that support muscle attachments and joint articulation. The other bones listed are in the hand or wrist—phalanges are finger bones, carpals are wrist bones, and metacarpals are palm bones—so they do not occupy the upper arm.

The long bone in the upper arm is the humerus. It runs from the shoulder to the elbow, acting as the main lever for arm movement. Its proximal end forms a joint with the scapula at the shoulder, and its distal end forms the elbow joint with the forearm bones. The humerus is characterized by a long shaft (diaphysis) and rounded ends (epiphyses) that support muscle attachments and joint articulation. The other bones listed are in the hand or wrist—phalanges are finger bones, carpals are wrist bones, and metacarpals are palm bones—so they do not occupy the upper arm.