18 SKELETAL SYSTEM

 SKELETAL SYSTEM

a. Skeletal system is instrumental in performing movements such as walking of grasping

b. The frame work of bones and cartilage that protects our organs and allows us to move isa called skeletal system.

Functions

The skeletal system performs the following functions:

(i) support : It provides a frame work for the body It supports soft tissues. It makes available surface for attachment of many bones.

(ii) Protection : It protects internal organs from injury.

(iii) Movement facilitation : It helps in movement.

(iv) Mineral storage : The bones are storehouses for minerals - calcium and phosphorus.

(v) Hematopoiesis : Bone marrow in certain bones is capable of producing blood cells in a process called hematopoiesis or hemopoietic.

Type of Bones

Almost all bones of the body may be classified in to four main types on the basis of shape.

(i) Ling bones: e.g. bones of the thighs, legs, toes, arms, forearms and fingers,

(ii) short bones : e.g. wrist and ankle bones.

(iii) Flat Boones : e.g. cranial bones, sternum, ribs and scapula's.

(iv) irregular bones : e.g. vertebral and facial bones.

Division of the skeletal system

Two skeletal system can be divided in to:

1. Axial skeleton : It consists of bones that lie around the axis e. g ribs breast bone, etc.

2. Appendicular skeleton : It comprise free appendages that connect upper and lower limps and girdles to the axial skeleton.

The adults human skeleton consists of 206 bones in different forms.