Question

What is lymph? Describe its functions.

Answer 1

Hint: Our body contains a colorless fluid containing white blood cells, specifically the lymphocytes which wash off many infectious agents like bacteria and are known as lymph. It runs throughout the body via channels known as lymph vessels which take the lymph to the tissues and drains it back into the lymph nodes.

Complete answer:
As the blood passes through capillaries in the tissues, some of the water along with many small water soluble substances moves out into the interstitial space leaving behind the large proteins and other elements in the blood vessels. This released out fluid present in interstitial space is called interstitial fluid or lymph. A broad network of vessels usually known as lymphatic system collects and drains it back to the major veins.

The main functions of lymph are:
- It maintains the balance of fluid between blood and tissues. This is also known as fluid homeostasis.

- It is a part of the immune system of the body which helps to defend against the bacteria and other microorganisms. Lymph has a very rich content of lymphocytes which act against infections readily.

- It is also observed to facilitate the absorption of fats and fat soluble nutrients in the digestive system. During fat digestion, fatty acids are digested and converted into chylomicrons (chylomicrons are a type of lipoprotein). Lymph vessels that line the intestine absorb these chylomicrons and take these chylomicrons into the liver via bloodstream for further breakdown.

Note:
The lymphatic system is the site of many key immune system functions. It is very necessary to know that immune system functions can happen almost anywhere in the body, but the lymphatic system is the system in which many immune system functions can take place simultaneously. Furthermore, the lymph system has small vessels called lacteals which absorb the fats and fat soluble nutrients from the intestine. These work with blood capillaries in finger-like projections (villi) of the intestine where blood capillaries absorb nutrients directly from the intestine.