Structure of the Bone - Essay Example

Anatomically, the human skeleton is classified into two parts. These include the axial skeleton and the appendicular skeleton. The central structural framework of the bones of the human body is known as the axial skeleton. This consists of eighty bones. The bones of the axial skeleton include the facial bones, bones of the cranium, hyoid bone, auditory ossicles, sternum, ribs, vertebrae, sacrum and coccyx. On the other hand, the appendicular skeleton is made up of the bones of the upper and the lower limbs as well as those bones that connect these limbs to the central axial skeleton.

The number of bones in the appendicular skeleton is 126. The bones of the upper limb include the humerus, radius, ulna, carpals, metacrapals and phalanges. The bones of the lower limbs include femur, patella, tibia, fibula, tarsals, metatarsals and phalanges. The connecting bones of the appendicular skeleton are referred to as the girdles. There are two girdles which include the pectoral girdle and the pelvic girdle. The pectoral girdle connects the upper limbs with the axial skeleton. Clavicle and the scapula are the bones of this girdle.

The pelvic girdle connects the lower limbs to the axial skeleton. The hip bones form the pelvic girdle. . For example the human brain is protected from injury by the bones of the skull. The ability of the human body to wear weight is also owing to the support of the bones. The bones are also the sites for the origin and insertion of muscles. Thus, the bones along with the muscles assist in the movement of the human body (Abernethy 2005; Plowman and Smith 2007). The physiological function of the bone includes the synthesis of blood cells which occurs in the bone marrow.

This process is referred to as hematopoiesis. The bones are also important for the maintenance of immunity in the human body because white blood cells are also synthesized by the bones. Important minerals of the human body which include potassium and calcium are also stored within the bone. These minerals are extremely important for the travelling of nerve impulses, proper contractility of the heart and the muscle, formation of energy sources in the body as well as the clotting of blood. Thus indirectly, the normal functioning of the bone is essential for these important bodily processes to be carried out.

The structural performance of the bone itself is dependent upon the calcium that is stored in it. Bones work for the regulation of the calcium levels in the blood and when the levels of calcium in the blood drop, the bone undergoes resorption and the stored calcium is released into the blood. Thus calcium regulation is another function of the bone (Abernethy 2005; Plowman and Smith 2007). Bone is a type of connective tissue and the ground substance of the bone is made up of collagen as well as cells.

The calcium and phosphorus which is present in the ground substance provides for the strength of the bone and makes it hard. The weight of the bones is mainly due