What is life? The exact definition even Biologists have trouble explaining! But living things have a life, a length of time to live. Living things need the following:
1) Living things need to take in energy.
2) Living things get rid of waste.
3) Living things grow and develop.
4) Living things respond to their environment.
5) Living things reproduce and pass their traits onto their offspring.
6) Over time, living things evolve (change slowly) in response to their environment.
Life is every system that resists entropy on account of the surrounding environment.