Blood

Blood is a connective tissue which connects all the body organs & tissues  with each other for proper functioning of the body systems . It consists of many components which includes plasma &  blood cells, (RBC, WBC & platelets)

Plasma :- It contains about 90-92 % water. It is straw coloured fluid , contain all the dissolved substances including sodium, potassium, manganese & calcium ions in it  It also contains hormones & proteins. Plasma acts as a medium in which the blood cells are transported around the whole body. It also helps to maintain body temperature & pH of the blood.

Red Blood Cells ( Erythrocytes) :- Mature RBCs are lack of nucleus. They contain active haem which relies on the presence of iron. Haem combines with oxygen & forms  unstable oxyhaemoglobin which breaks in the cells to release oxygen for respiration & takes away carbon dioxide from the cells . RBCs are broken down by the spleen into blood pigments. These components are then transported by the blood to the liver where iron is re- cycled for use by new RBC formation. The life cycle of RBCs are approximate 120 days. The concentration of RBCs are approximate 4.5.-5.8 milllions per micro liter of healthy human blood.

White Blood Cells (leucocytes) They are the major part of immune system.They are also called body soldiers.  The life cycle of WBCs are few hours to few days but some are remain for many years. These are approx 5,000-10,000 per micro liter of blood.

Platelets (Thrombocytes) Blood platelets are cell fragments helps in coagulation of blood at the site of injury.  The diameter of platelet cell is about 2-4 micro meter. These cells do not contain nucleus but it contains many granules. These are approx 150,000 to 40,0000 per micro liter of blood.  

By : – Dr. Rashmi Dhingra

Principal
Uttaranchal (P.G.) College of Biomedical Sciences and Hospital,