Question

mates plz answer this....
why do sponges nd hydra not have blood....no copping nd no spam..

Answer 1

• sponges and hydra do not need blood as they do not posses any circulatory system. the water in which they are living in, acts as food and oxygen when it enters their bodies. when this water moves out, it takes away waste materials and carbon dioxide.

Answer 2

sponges and hydra are very small organisms.
these organisms don't need much energy for there daily processes.
these organisms don't even need a partner to reproduce.
these organisms have a very simple structure and the process of transfer of food in body is not required.