Question

Sutural joints are present between
A. Thumb and metatarsal
B. Humerus and radio-ulna
C. Parietals of skull
D. Glenoid cavity and pectoral girdle

Answer 1

Hint: The location at which two or more bones make contact is a joint. They are built to allow motion (with the exception of skull bones), provide mechanical support and are structurally and functionally graded. Fibrous joints are often called fixed or immovable joints because they do not move.

Complete Answer:
- There is no joint cavity of the fibrous joints, such as sutures, syndesmosis, and gomphoses. Dense connective tissue, composed primarily of collagen, binds fibrous joints. Normally, the adult skull is made up of 22 bones. All are joined together by sutures, semi-rigid articulations created by bony ossification, except for the mandible.
- A little versatility is required by the existence of Sharpey 's fibres. By tightly uniting the neighbouring skull bones, the fibrous connective tissue of a suture helps protect the brain and shape the face. Sutures form a tight union which prevents most of the bones from moving. Most of the sutures are named after their articulated bones.
- The frontal, parietal, temporal, occipital, sphenoid, and zygomatic bones are the skull sutures visible from the side (norma lateralis), while the skull sutures visible from the front (norma frontalis) and above (norma verticalis) are those connected to the frontal and parietal bones.
- The frontal, ethmoid, and sphenoid bones have skull sutures evident from below (norma basalis).
- The connective fibrous tissue contained in a suture (to attach or sew) strongly unites the adjacent bones of the skull and thus helps protect the brain and shape the face. The skull bones in adults are closely opposed and the small distance between the bones is filled by fibrous connective tissue. Sometimes, the suture is convoluted, creating a tight union that prevents most bone movement.

The correct Answer is option (C) Parietals of skull.

Note: A matrix of connective tissues called Sharpey's fibres, which develop from each bone into the adjoining one, are bound together by sutures. Sutures are allowed to have a limited amount of movement, adding to the compliance and elasticity of the skull. Synarthroses (immovable joints) are such joints.