Why do animals need a circulatory system?

1 Answer
Aug 9, 2016

For distribution of metabolites, respiratory gases and waste material.

Explanation:

Multicellular organisms have many cells. Each cell should get food molecules, respiratory gases and waste material from cell should be carried away. Circulatory system circulates everything. Keeps cell environment homeostatic. That is why circulatory system is a must for multicellular organisms.