Why is blood needed by all the parts of a body?
Blood is needed by all parts of the body as it is an important part of the transport system of our body. It performs the following important functions:
(i) It transports O2 from the lungs to all the body cells.
(ii) It carries CO2, a waste product back to the lungs so that it can be exhaled easily.
(iii) It transmits heat, thus regulating the body temperature.
(iv) It also fights off diseases and infections.