system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are cells living? I know they’re the building blocks of life but what defines living? Are plants a different type of “alive” because they have a different cell structure?
gpt
The current definition of life simply states that for an organism to be considered living, it has to maintain **homeostasis**, which is the technical way to say "it has to maintain itself through its metabolism".

A cell maintains itself by breaking down resources to extract the energy and elements it contains, making up complex structures to achieve survival and reproduction. From bacteria, to protozoa, to algae, to plants, to fungi, to animals, we observe this behaviour, regardless of the cell type.

In a sense, all lives are the same, they're just living - and have been living - under different circumstances that greatly affect how they "express life".