Exchange of substances between a cell and its environment is due to

Exchange of substances between individual cells and their environments takes place by

The exchange of gases between organism-and environment is called as

Fill in the blanks _______ allows exchange of substances between nucleus and cytoplasm.

Study of interrelationships between a species and its environment is called:

The ......... is the boundary between a cell and its environment.

Explain the transfer of energy between system and its environment.

Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment.