Which of the following are correct tenets of Cell Theory?

(1) Cells are the fundamental units of life

(2) Cells are the smallest entities that can be called living

(3) All organisms are made up of one or more cells

(4) Cells arise only from the division of other cells

Explanation

Cell Theory has four accepted tenets (as presented in the self-test):

1. Cells are the fundamental units of life.
2. Cells are the smallest entities that can be called living.
3. All organisms are made up of one or more cells.
4. Cells arise only from the division of other cells.

"All cells have a cell wall" is incorrect — animal cells do not have cell walls.