What is Skeleton?

Hint: It is a hard structure that protects the internal organs of living things.
All the bones, when joined together, make up the skeletal system of a body.
The skeletal system or skeleton is present beneath the skin, the muscle and the tissue of the body.

Complete answer:
The skeletal system is the body system composed of bones, cartilages, ligaments and other tissues that perform essential functions for the human body.
Bone tissue or osseous tissue is a hard and a very dense connective tissue that forms most of the adult skeleton
It is also known as the internal support system of the body.
In human beings, the skeleton is made up of 206 bones and a few cartilages.
It is grouped into two principal divisions
1. Axial skeleton
2. Appendicular skeleton
Axial skeleton comprises 80 bones which are distributed along the main axis of the body.
It consists of:
1. The skull
2. Vertebral column
3. Sternum
4. Ribs
Skull consists of two sets of bones:
1. Cranial bones
2. Facial bones
Vertebral column in human beings is formed by 26 vertebrae.
Sternum is a flat bone present on the ventral midline of thorax.
There are mainly 12 pairs of ribs in the human body.
Each rib is a thin flat bone which is connected dorsally to the vertebral column and ventrally to sternum.
Appendicular skeleton consists of bones of the limbs along with their girdles and each limb is made up of 30 bones.
Pectoral girdle bone helps in articulation of upper limbs whereas pelvic girdle bones help in the articulation of lower limbs with the axial skeleton.

Note: Some of disorders of muscular and skeletal system are:
1. Myasthenia gravis: It is an autoimmune disorder affecting neuromuscular junction leading to fatigue, weakness and paralysis.
2. Arthritis: It is the inflammation of joints.
3. Osteoporosis: It is an age-related disorder characterized by decreased bone mass and increased chances of fracture.
4. Tetany: It is rapid spasms in muscle due to low calcium in body fluids.