Question

cells are alive, but not all living cells are organisms.explain

Answer 1

In order for something to be considered an "organism," it must have the capability to function independently. That is, it must be able to survive without the help of other cells. The Amoeba is made up of a single cell and is capable of living independent from other cells. Other types of single celled organisms include the euglena and the protist.

Conversely, cells that make up skin, for instance, function as a single unit, but are made up of many individual cells. These cells are doing one job and individual skin cells cannot live without the other cells. They are therefore not considered organisms.

Think of it this way:
Animals and humans can live independently and are therefore considered organisms.
However, if we were to take individual cells from the human or animal's body and put them under slides in a lab, those cells would no longer be able to sustain themselves without the help of other cells in the human or animal's body.
Single-celled organisms, like protists and amoebas, would be able to live under a slide in a laboratory completely separate from other amoebas or protists.

Answer 2

all living organisms are not cells because they need to be able to function in a certain way(: