Question

what is lymph?? and its function and where it is present...

Answer 1

Lymph is the fluid that flows through vessels and nodes of the lymphatic system. It is formed when the interstitial fluid (the fluid which lies in the interstices of all body tissues) is collected through lymph capillaries. Lymph may pick up bacteria and bring them to lymph nodes, where they are destroyed.
It absorbs the digested fats from the small intestine and provides immunity and fights infection.
It flows inside the lymph vessels.

Answer 2

a colourless fluid containing white blood cells, which bathes the tissues and drains through the lymphatic system into the bloodstream