In relation to biology, in the study of evolution, what would one say it is to be alive?

In the environment there are biotic and abiotic factors
that are both important. Abiotic factors include things like temperature, water,
climate, oxygen, amount of sunlight, etc. These are important to living things, but are
not in any way alive. However, biotic factors are all the populations in an ecosystem.
To be deemed "alive" an organism must carry out certain life functions. These include
respiration, nutrition, digestion, circulation, reproduction, excretion, growth, etc.
Therefore, when examining an ecosystem, there is a connection between abiotic and biotic
factors, however, the biotic factors are all the organisms capable of carrying out the
life functions mentioned above. A living thing can be a bacteria, fungus, protist, plant
or animal. And in terms of evolution, any living thing that survives in its environment,
due to the adaptations it possesses, and then goes on to reproduce, is not only alive,
but is also considered "fit".