The Elixir Of Life ? – Delving into the mystery that is blood
JUNE 9, 2013
There are many legends about the elixir of life, a liquid that will keep one young forever. Perhaps they are mistaken. It’s your blood that keeps you alive. Its functions are manifold and without it, you cease to be.
A flashback to your biology class
The average adult body has about 5 litres of blood. This living tissue performs a number of roles in your body. But first, what is your blood made of?
A few blood facts
Human blood comprises of four components. Red blood cells or erythrocytes are the most abundant cells in your blood. These transport haemoglobin, a protein that carries oxygen to every cell in your body.The white blood cells, leukocytes, are part of the immune system and work to destroy infection. There are five different types of leukocytes, including lymphocytes. Plasma is the yellowish liquid portion of your blood. It contains electrolytes, nutrients and vitamins, hormones, clotting factors (platelets) and antibodies that fight infection. The platelets or thrombocytes are responsible for clotting. When you have a wound, they join together to form a seal, thus preventing lood loss.
An intricate transportation system
Your blood circulates through your blood vessels, namely the arteries, the veins and the capillaries. The arteries carry oxygen-rich blood to the body’s tissues; the capillaries enable the exchange of water and chemicals and the veins transport blood with carbon dioxide to the lungs.
Your blood also carries heat through the body, nutrients from the digestive system to your cells and removes the waste products from your body. It transports your hormones, regulates acidity levels, protects you against infection and is responsible for the clotting of wounds. In short, it keeps a clean house.
Blood types, antigens and more
We’re often asked for our blood type, mainly while filling out forms! You could have A, B, AB or O type blood. Blood types differ according to the antigens carried by your RBCs. Antigens are substances that induce the production of one or more antibodies.
There are two antigens, A and B. If you have the A antigen on your RBCs, then your blood is type A; your blood type is B when the B antigen is present. If your RBCs have both A and B antigens, you have type AB blood. It is type O blood when neither antigen is present.
When disorder reigns
When the cells that make up your blood behave abnormally, it affects your entire system. Blood disorders can be acute or chronic; many are inherited. They are also caused by other diseases, side effects of medications and the lack of certain nutrients in your diet. Common blood disorders include anaemia, bleeding disorders, blood clots and blood cancers.
When your ‘Clotters’ Fail
One of the most important functions of blood is to prevent bleeding. If your blood has insufficient platelets, you could bleed uncontrollably. In India, the most common cause for bleeding is immune thrombocytopenia (ITP), a disorder where the patient has insufficient platelets and tends to bleed internally or underneath the skin. Infections such as dengue can also cause bleeding from the nose, gums and under the skin.
Platelet dysfunction, where the number of platelets in the blood is normal but the cells do not function normally, also cause bleeding disorders. Platelet count also drops significantly in patients who are in liver failure or have certain types of cancer, liver disease, massive tissue injury and certain viral, bacterial and fungal infections. Haemophilia A & B are the most common inherited bleeding disorders.