Human Beings are Complex Colonies of Individual Cells

[MineralMan]

5. OK. However, we are made of billions of individual, specialized

cells. So is a rotifer or a flea. Each type of cell has specific things to do. Muscle cells, for example contract when stimulated. The cells in the retina of your eye generate an electrical impulse when light hits them. They are far less alike than they are different.

You are correct that most human cells cannot survive outside of the organism. Sperm cells are about the only ones that do that, and they survive for only two or three days. Still...

Our cells are specialized and there are thousands and thousands of different types of cell in our body. We are a cell colony, just like a rotifer is a cell-colony, or a jellyfish. It is the types and organization of the cells that make each organism what it is.