SKELETAL SYSTEM
Human skeletal system is commonly called the framework of the body; this is because it shapes the human body. This ‘framework’ consists of bones, cartilages and joints. Joints are a vital component of the skeletal system as it makes up the firm and stiff skeleton which enables different parts of the body to make various types of movements, therefore if the joints weren’t present in the skeleton; there would be no movement leading to the human body becoming rather insignificant.
Human skeleton is composed of three main components; Bones, Cartilages and Joints.
Bones:
Bone is the strength and weight bearer in the body. It is responsible for most of the strength in the body. It is a strong and stiff type of connective tissue.
Cartilages:
Cartilage is a less tough form of connective tissue. The main variance between cartilage and bone is the fact that bone is highly mineralized with calcium salts whereas cartilage isn’t.
Joints:
Joints are a vital component as they enable the human skeleton to move. A joint occurs between ‘two or more bones’, ‘cartilage and cartilage’ and ‘bone and cartilage’
The human skeleton has two divisions: the axial skeleton the appendicular system.
Axial Skeleton
As the name suggests, the axial skeleton forms the axis of the body and consists of the skull, vertebral column, thoratic cage.
Skull:
Skull is the part which forms the structure of the head which tends to be bony. It is divided into two groups; bones of cranium and bones of the face, in total it consists of 22 bone.
Vertebral Column:
The vertebral column is a bendable column of vertebrae which links the trunk of the human body to the skull and the appendages. It has five regions; Cervical, Thoratic, Lumbar, Sarcal and Coccygeal and consists of 33 vertebrae.
Rib cage:
It is a cage surrounding important human organs which are developed by the sternum and ribs. The rib cage consists of 12 pairs of ribs which are divided into to three sections; true ribs, false ribs and floating ribs.
The appendicular system it is the skeleton for all the appendages in the human body. It is composed of shoulder girdle, skeleton of upper limb, pelvic girdle and skeleton of lower limb.
Shoulder Girdle:
The shoulder girdle has the role of linking the upper limb to body trunk and is formed by the clavicle and scapula. The scapula holds three important activities; spine of scapula, acromion process and the cocarcoid process. The scapula bone is a flat bone which is also pear shaped and retains the glenoid fossa for the formation of the shoulder joint. The clavicle (also known as the beauty bone) is a modified long bone.
Skeleton of Upper limb:
Each upper limb has a skeleton which is composed of 30bones. These bones are carpals (8), metacarpals (5) phalanges (14), ulna, radius and humorous.
Pelvic Girdle:
There are two pelvic girdles, one for each lower limb. Each pelvic girdle is a single bone in adults and consists of Ileum, Ischium and Pubis. The pelvic girdles are jointed together by symphysis pubis.
Skeleton of Lower limb:
The skeleton of each lower limb composed of 30 bones. There are bones are femur, tibia, patella, tarsals(7), metarsals (5), phalanges(14)
Functions of human skeleton:
Human skeleton performs some important functions that are necessary for survival of human beings.
Strength, support and shape:
It gives strength, support and shape to the body. Without a stiff and rigid system, the human cannot stand straight and will have no shape.
Protection of delicate organs:
The skeletal system protects soft but vital organs such as the heart and brain in areas like the rib cage and skull. It protects these vital organs from external damage. This is a very important function as any injury to these organs can be a matter of life and death.
Leverage for movements:
The muscles all provide mobility power to allow the body parts to move, the skeleton acts like levers of different types