In all organisms, cells are the most basic units of structure and function. The structure of an organism is affected by the way its cells are shaped and organized. Many of the functions that an organism needs to carry out to stay alive happen inside its cells. A cell is the smallest unit that can get and use energy, remove waste, and carry out other processes necessary for life.
The micrographs below show cells from two different organisms: an onion plant, which is multicellular, and a diatom, which is unicellular.




onion cells

a diatom

Complete the table to describe the organisms shown in the micrographs above.