The skeletal system of our body comprises of the bones, that form the skeleton, the cartilages, which are the rubbery soft connective tissues found in the joints, ear, nose, and ribs, and the ligaments, which are the fibrous tissues, which connect one bone to the other. The functions of the skeleton form the basis of functioning of the human body. A child is born with 270 bones, which goes down to 206 bones marrow, and blood vessels. The bone marrow and blood vessels are composed of nerve cells, fat cells and various other connective tissues. The osseous tissue forms the hard and rigid part of the bone, which calcifies over time, by deposition of minerals, and hardening it, and it reaches its maximum density by the age of 30.
There are two kinds of tissues inside the bones:
- Compact bone: This stiff and dense tissue amounts to the outer layer of most of the bones and the key shaft of long bones, such as those in the arms and legs. Nerves and blood vessels live inside this tissue.
- Spongy bone: This tissue consists of smaller discs filled with red bone marrow. It is found at the finishes of long bones, like the head of the femur, and at the center of other bones.
Apart from providing the body with a frame, the skeleton has various other important functions, like supporting, shaping, protection, mobility, etc.
Functions of the Skeleton
The human body is made up of the most complex skeletal system, which not only shapes the body but also helps us to stand erect and walk on two legs, unlike any other living being. The functions of the skeleton are not just limited to one but several aspects that are essential for the proper functioning of the human body. Another special feature is having opposable thumbs. These features distinguish us from the others and make us functionally exceptional. Some of the distinguished functions of the skeleton is discussed below:
- Shape: Shaping our body is one of the primary functions of the skeleton. The shape and size of the body, face and even the hands and legs largely depend on upon the skeleton. As the bones grow in size gradually with age, they form our shape. Though it also depends on upon the genes acquired, the bones are the ultimately responsible. A man with tall and thin bones is ectomorphs. Short people are mesomorphs and endomorphs are those whose skeleton makes then apple or pear shaped. Dwarfs are another kind whose bones are very small in size.
- Support:The maintenance of the shape of the body is also one of the functions of the skeleton. It supports the internal organs to stay in their respective places. The spinal cord is responsible for supporting the upper part of the body, while the ribs make sure that the heart and lungs are properly supported. The skull holds the brain, and the abdominal structure holds the gastrointestinal organs. The whole weight of our body is taken care of by the long bones in our legs.
- Movement:The nervous system controls the whole movement mechanics. It includes coordination of the skeleton, muscles and the joints. The bones and muscles together form the musculoskeletal system. They work together to make the human body agile and mobile. The muscle contraction pulls on the bones, resulting movements. The cartilages, ligaments and tendons, which are the connective tissues of the skeletal system, make the movements possible. However, the joints and the size of the bones are the determining factors in the range of movements. The joints like finger joints have limited movements, while ball and socket joints such as hips and knees are more movable. Hence, movement is one of the very important functions of the skeleton.
- Protection:The hard and bony structure of the skeleton forms small encasings for the soft vital organs of our body, to protect them from a direct impact or injury. The skull protects the brain. The spinal column is responsible for the spinal cord and nerves, whereas the ribs and the sternum, which forms the thorax protects the heart, the lungs and important blood vessels. The flexibility is due to a constituent called collagen. The mixture of power and flexibility gives the skeleton the volume to absorb the effect of blows to the body without breaking. Out of all the functions of the skeleton, protection, especially by the skull is essential for survival in situations like accidents or sudden fall.
- Blood Cell Production. Apart from osseous tissues, the bones are comprised of the bone marrow and the blood vessels. The bone marrow is of two types. There is the red bone marrow which produces about 2.6 million RBC per second. The yellow bone marrow stores fat, which can later be transformed into RBC in a case of anaemic patients or heavy depletion of RBC. Bigger bones contain bone marrow, a spongy tissue inside the bones. There are two main types of marrow, red and yellow. Red marrow is accountable for making of all of the body’s red blood cells and several white blood cells.In adults, red marrow is found primarily in the breastbone, hips, ribs, skull, and spine bones and at the end of long bones of the arms and legs. Several types of white blood cells, which guard the body from infections, are also produced in red bone marrow. Yellow bone marrow comprises primary fat cells but can convert into red marrow if the body wishes to upsurge blood cell production.
- The minerals like calcium and phosphorus, which are stored in the bones are very useful for the body as they help in maintaining a healthy metabolism and unhindered nerve transmission.
- Endocrine Regulation. As stated above, the bones are found responsible for maintaining a healthy sugar metabolism due to the presence of minerals like calcium and phosphorus. A healthy metabolism results in a healthy weight. A hormone called osteocalcin, is released by the skeleton, which controls type 2 diabetes, and also a regular distribution of fat. This hormone is also responsible for the increase in insulin production, thus regulating blood sugar. Endocrine regulation is a highly necessary element as regards the functions of the skeleton.
- Electrolyte Balance. It is necessary to maintain a right electrolyte balance in the body as, they helps in blood chemistry, reflexes, and other activities. Important electrolytes like calcium and phosphorus are present in the bones.
- Acid-Base Balance. A person’s acid-base balance is evaluated by measuring the Ph levels and levels of co2 and bicarbonate present in the blood. The bones lessen or moderate the changes in these levels.
From the above discussion, we can get a clear notion that the skeleton apart from, forming the structure of your body has a major role in the mobility, protection, and maintenance of the body.
Common conditions that affect the skeleton
Some common conditions that affect the functions of skeleton are:
- Osteoporosis :- It is a disease in which the bones become fragile and highly prone to fractures. In literal terms it means “porous bones”.
- Leukemia :- It is the cancer of bone marrow and white blood cells.
- Osteopenia, Osteomalacia :- These are also diseases of the bone, which finally result in weakening of the bone and bone loss.