Cells #braincellsinuse

The smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane.

Animal cells do not have a cell wall or chloroplasts but plant cells do. Animal cells are round and irregular in shape while plant cells have fixed, rectangular shapes.

Muscle is simply physical power and strength. A nerve is a person's mental state, in particular the extent to which they are agitated or worried. A bone is  any of the pieces of hard, whitish tissue making up the skeleton in humans and other vertebrates.

respiratory system

this is somewhat the same as other organisms