Question

The only movable part of the skull is
a. Upper jaw
b. Lower jaw
c. Both A & B
d. None of these

Answer 1

Hint: The brain is enclosed in the hard cranium of the skull. The bones which make up the cranium are called the cranial bones. The remaining bones of the skull are known as the facial bones.

Complete answer:
The skull contains bones like the Occipital bone, Frontal bone, Mandible, Temporal bone, Parietal bone. The only one movable joint in the skull is the joint connecting the mandible or lower jaw, to the rest part of the skull. Mandible is the largest, strongest and lowest bone found in the human face. It forms the lower jaw and also holds the roots of lower teeth in place. The mandible or lower jaw is the only movable part of the skull that takes part in formation of the temporomandibular joint with the temporal bone.

Among the given options: The maxilla is the bone that forms the upper jaw. The two major halves of maxilla, right and left halves, are irregularly shaped bones that fuse together in the middle of the skull, below the nose.

So, the correct answer is option B.

Additional Information:
During fetal and childhood development, the skull bones remain somewhat separated, which allows the growth of the brain and skull. Upon reaching maturity, the skull bones fuse together to form a rigid protective shell for the soft tissues of the brain. The only bone that remains separate from the rest of the skull is the mandible, or lower jaw bone.

Note: The human skull is a bony cage that forms the head. It supports the structures of the face and provides a protective cavity for the soft tissues of the brain. Every bone in the skull is fused, except for one movable joint.