What is blood? Why is it called a connective tissue?
Answers
the red liquid that circulates in the arteries and veins of humans and other vertebrate animals, carrying oxygen to and carbon dioxide from the tissues of the body.
Blood is considered a connective tissue for two basic reasons: (1) embryologically, it has the same origin (mesodermal) as do the other connective tissue types and (2) blood connects the body systems together bringing the needed oxygen, nutrients, hormones and other signaling molecules, and removing the wastes.
Blood and lymph both are fluid connective tissues. The main function of fluid connective tissue are binding, protecting and connecting together different organs of the body. Blood and lymph both has these qualities that's why we called them connective tissue.
Let us see how they fullfil these qualities :
- Binding : (a) Blood : it carries oxygen, carbon dioxide, digested food, hormones and waste product (urea) from one part to another. (b) Lymph : it carries large protein molecules, digested fat, germs and fragments of dead cells from the tissue fluid around the body cell seeps into the lymph capillaries.
- Protecting :(a) Blood : protect the body from diseases with the help of WBC(white blood cells). (b) Lymph : protect protect the body by killing the germs drained out of the body tissue with the help of lymphocytes.
- Connecting different organs :(a) Blood : it connects together each and every part of the body. As blood is necessary for whole body. (b) Lymph : it connects body tissues to the heart.
You can better understand this by reading blood circulatory system and lymphatic system once.