AP BIOLOGY

Detailed explanation-1: -Cells are so little, so they can maximize their ratio of surface area to volume . Smaller cells have a higher ratio which allow more molecules and ions move across the cell membrane per unit of cytoplasmic volume. Cells are so small because they need to be able to get the nutrients in and the waste out quickly.

Detailed explanation-2: -The smallest cell is Mycoplasma gallicepticum. It is about 10 micrometer in size. The largest cells is an egg of ostrich.

Detailed explanation-3: -At 0.1 to 5.0 m in diameter, prokaryotic cells are significantly smaller than eukaryotic cells, which have diameters ranging from 10 to 100 m.

Detailed explanation-4: -Cells are so small because they are easier to replace, and a cell needs to be small to be able to perform the tasks a cell needs to do. If cells were bigger it would be harder for the body to replace the cell without disrupting what is going on in the body and delaying a process.

Detailed explanation-5: -Larger is not necessarily better when it comes to cells. For instance, cells need to take in nutrients and water through diffusion. The plasma membrane surrounding cells limits the rate at which these materials are exchanged. Smaller cells tend to have a higher surface area to volume ratio than larger cells.