New Jersey State Board Esthetics Practice Exam

What is the largest bone in the arm?

1. Radius

2. Ulna

3. Clavicle

4. Humerus

The correct answer is: Humerus

The largest bone in the arm is the humerus. This long bone extends from the shoulder to the elbow, playing a crucial role in the structural framework of the upper limb. The humerus not only provides support for the arm but also serves as an important site for muscle attachments, enabling a wide range of movements such as raising the arm and lifting objects. In comparison, the radius and ulna are both located in the forearm, with the radius being on the thumb side and the ulna on the opposite side. While they are essential for forearm function and movement, particularly in wrist and elbow motion, they are shorter and smaller in comparison to the humerus. The clavicle, or collarbone, is not considered part of the arm itself—it connects the arm to the body and supports shoulder movement, but it is classified separately from the upper arm bones.