they need a lot of energy
They need to stay alive to support the organism
Oxygen is needed to stay alive. Without it you suffocate.
The four thing you need to stay alive are: Oxygen, water, Food, and Air
Enviorment
To stay alive
breath and crap like that
to stay alive
Water to swim in
The Romans needed water, food and shelter to stay alive just like everyone else.
It does need resources.
Oxygen, Energy, and Nutrients
Water and nutrients