Question

Head of the humerus is articulated with a pectoral girdle by ---- joint.
(a) Hinge
(b) Ball and socket
(c) Immovable
(d) Pivot

Answer 1

Hint: Head of the humerus is articulated with a pectoral girdle cup-shaped joint. It is mobile on all flights and exhibits rotation as well. This joint is located in the region of the shoulder and hip that facilitates all radial motions such as forward, backward, sideways, and rotation. Also known as a spheroid joint.

Complete step by step answer:
Each scapula or pectoral girdle contains a concave, articular surface called the glenoid cavity that articulates with the humerus head. The ball-like the humerus head articulates with the glenoid cavity and creates a ball and socket joint and allows great motility for the upper limb.
The ball and socket joints are created by one bone's rounded or "ball-shaped" head fitting into another bone's cup-like cavity. The articulating bone fits into the cavity and helps it to travel around the distal bone.
Hinge joints are the ones that allow one plane to move. They facilitate actions such as bending and straightening, such as flexing a finger.
Protective cartilage covers the bones in a hinge joint and they are lubricated by a thick gel called synovial fluid, allowing them to move without rubbing against each other.
In vertebrate anatomy, the pivot joint, also known as the rotary joint or trochoid joint, is a freely rotating joint (diarthrosis) , which enables only rotational movement around a single axis.
An immovable joint is an articulation between bones, where there is no movement. An immovable joint may either be one of two fibrous or cartilaginous joints.
There are two types of articulations in a fibrous joint which are considered motionless, suture, and gomphosis. There is one form of articulation in a cartilaginous type of joint which is considered immovable, the synchondrosis.

So, the correct answer is, ‘(b) Ball and socket’.

Note: The pectoral girdle consists mainly of the clavicle and the scapula that is used to attach the upper limb to the axial skeleton's sternum. The clavicle, which also articulates with the humerus (arm bone) to form the shoulder joint, supports it. Other parts of the body, including the wrist and ankles, need at least two different joints to work together to perform all of the ball-and-socket joint movements.