Question

Which one of the following statements is true?
A) Head of the humerus bone articulates with an acetabulum of pectoral girdle.
B) Head of the humerus bone articulates with the glenoid cavity of the pectoral girdle.
C) Head of the humerus bone articulates with a cavity called acetabulum of pelvic girdle.
D) Head of the humerus bone articulates with a glenoid cavity of pelvic girdle.

Answer 1

Hint: The humerus is the long bone present in the arm which stretches from the shoulder to the elbow. Around 13 muscles attach with the humerus which helps in the movement of the upper limb and the elbow.

Complete answer:
To answer this question, we must know about the structure of humerus. The humerus is a long bone of the upper appendage, which reaches out from the shoulder to the elbow.

Structure of humerus- It consists of a proximal end, a shaft and the distal end. The proximal part of the humerus expresses with the glenoid fossa of the scapula, forming the gleno-humeral joint. It articulates proximally with scapula and distally at the elbow with both ulna and radius. Humerus articulates with the glenoid cavity of the pectoral girdle. (Statement B is correct).

Statement A is incorrect as the acetabulum is the socket of hip bone. The head of the thigh bone articulates with the acetabulum of the pelvic girdle.
Statement C is incorrect as the head of femur articulates with the pelvic girdle of the hip bones.
Statement D is incorrect as the glenoid cavity is present in the shoulder region not the pelvic region.

Hence, the correct answer is option (B).

Note: The humerus interfaces at the shoulder with a rotational joint. The humerus is instrumental in supporting a considerable lot of the arm's capacities. The other long bones in our body include femur in the upper leg and the radius and ulna in the forearm.