Question

Give two examples of ball and socket joints.

Answer 1

Hint: Ball and socket joint is a kind of joint that allows movement in all directions. In this joint one head of a bone fits into the cup like the cavity of another bone. It is also known as spheroidal joints.

Complete answer:
In the human body there are types of joints present out of them on the ball and socket kind of joint. In this joint round the head of one bone fits into the depression of another bone and makes a ball and socket joint, this permits movement in maximum direction than any other joint in the body. Examples of Ball and Socket joint are; Hip joint, Shoulder joint.

Hip Joint: This is the best example of a ball and socket joint. Hip contains articulation between the head of the femur bone and acetabulum of the pelvis bone. The acetabulum is a depression like cup that is located on the inferolateral aspect of the pelvis. This is a deep cavity-like structure where the head of the femur bone fits completely. This makes a perfect example of a ball and socket joint.

Shoulder Joint: It is another example of ball and socket joint, also known as glenohumeral joint. It is a ball and socket joint between the scapula and the humerus bone. This is a major joint because it connects the upper limb to the trunk. The shoulder joint is formed by the articulation of the humerus bone head fitted into the glenoid cavity of the scapula. Here, in this case the head of the shoulder is larger than the fossa due to this movement being in a wide range.

Hence, the correct answer is option (B).

Note: Basically joint is where two bones join each other. There are immovable joints in the human body, there are joints with mild movement and there are joints with free movement. Joints that are freely movable are; ball and socket joint, hinge joint, condyloid joint, pivot joint, gliding joint, saddle joint. Freely movable joints are known as Diarthroses, immovable joints are known as Synarthroses and Amphiarthroses are joints with slight movement.