Question

Which of these is the smallest?

A. cells

B. atoms

C. molecules

D. cell membranes

Answer 1

The smallest among the options provided is **B. atoms**.

To clarify the relationships:

- Atoms are the basic units of matter and are smaller than cells, molecules, and cell membranes.
- Molecules are made up of two or more atoms.
- Cells are the basic structural and functional units of life and are composed of molecules and cell membranes.
- Cell membranes encase cells and are composed of lipid and protein molecules.

Therefore, atoms are the smallest unit listed.