Because our bodies work to fight off unknown substances like bacteria
A eukaryotic cell is much more complex than a prokaryotic cell. Eukaryotic cells usually make up more complex organisms and have organelles such as endoplasmic reticulum, Golgi apparatus, mitochondria, a nucleus, and lysosomes. A prokaryotic cell only has circular chromosomes and is much smaller than a eukaryotic cell. Most single celled organisms are prokaryotes.
Eukaryotic cells are cells with a nucleus while prokaryotic cells do not have a nucleus.
Electric and mechanical energy
Cell Membrane. Even cells with cell walls have a membrane
