Question

The type of joint present between the humerus bone and the pectoral girdle is
A. Pivot joint
B. Ellipsoid joint
C. Gliding joint
D. Ball and socket joint

Answer 1

Hint: Joint is an articulation that connects the bones of the body. Joint allows a variety of movements of different body parts, for example – knee joint, elbow joint, wrist joint, etc.

Complete Answer:
1. Pivot Joint: Pivot joint is also called the rotator joint.
- In the pivot joint, two bones meet, one end will be a central bony cylinder and the other being a ring made up of bone or ligament.
- In some joints the cylinder rotates inside the ring and in other joints the ring rotates around the cylinder.
 Example – Proximal radioulnar joint, Distal radioulnar joint or median atlanto axial joint.

2. Ellipsoid joint: Ellipsoid joint is a type of synovial joint in which an oval bone fits into an elongated or ellipsoidal cavity of another.
- It allows movements such as flexion, extension, adduction and abduction.
- It is a joint in which two principal axes of motion are at right angles to each other.
 Example – wrist joint, metacarpophalangeal joint, metatarsophalangeal joint, etc.

3. Gliding joint: Gliding joint is also known as plane joint or planar joint.
- It is a common type of synovial joint.
- This joint is formed between the two bones that meet at flat articular surfaces.
- These joints allow the bones to glide past one another in any direction along the plane of the joint.
 Example – carpals joint or wrist, tarsal joint of ankle, facet joints of spine, etc.

4. Ball and socket joint: Ball and socket joint is also called a spheroid joint. It is also a type of synovial joint.
- In this type of joint, the ball shaped surface of one rounded bone fits into the cup like depression of another bone.
- This rounded surface of bone moves within the depression and allows greater freedom of movement than other kinds of joints.
 Example – shoulder joint, hip joint of mammals.

Hence, option D is the right answer for this question.

Note: Point to be noted that all the types of joints we have discussed above are synovial joints. These joints allow the movement of body parts and occur at articulating bones. The bones of synovial joints are surrounded by a synovial capsule which secretes synovial fluid and this fluid lubricates and provides nourishment to a joint and also acts as a shock absorber.