Cells are the basic unit of structure in all living things. ... Since cells are in all living things, they provide information about all life. Because all cells come from other cells, scientists can study cells to learn about growth, reproduction, and all other functions that living things perform
It is important that the subject does not know when the respiratory rate is being assessed because his or her knowledge might lead to the unreliability of the results. For example, the subject might get anxious and his or her breathing rate might increase, or vice versa.
A part of the body that doesn’t contain melanin is the nails