Blood is the red coloured fluid that flows
continuously in a human being's circulatory
system. Blood comprises
more than 8% of the body weight of a healthy
individual. On an average, every adult person has
about 5 - 6 litres of blood.
The major component of blood is a fluid called plasma in which are suspended cellular elements.
These are Red Blood Cells or RBC's, White Blood Cells or WBC's and tiny platelets.
Blood components, and what they do
Plasma acts as a vehicle to carry many substances like glucose, fats, and proteins,
enzymes, and hormones etc., in addition to the blood cells.
Plasma has protein components called albumin,
globulin and fibrinogen. Broadly speaking, albumin maintains the structural balance of blood, globulin
builds resistance to bacterial infections, fibrinogen helps blood coagulate.
Red Cells carry oxygen from the lungs to various
body tissues and take back carbon dioxide from the cells and tissues which the body
gets rid of as exhaled air.
The basic substance of red cells is iron and protein, known as haemoglobin. The haemoglobin
count is an indicator of the health of blood. On an average, a healthy male should have 14 - 16 gm
per 100 millilitre and in a female around 12 - 14 gm per 100 millilitre.
White cells act mainly as body scavengers and guards.
They help in the immune system of the body and act as defense forces of the body,
killing bacteria or any other organisms entering the body.
Platelets help in the clotting and coagulation of blood. They also repair the tiny blood
vessels in the body which crack under pressure, thereby preventing haemorrhages under
the skin.
