the fluid produced by the kidneys as they remove waste chemicals from the blood is known as urine. this substance is made up of water together with some and dissolved in it. the concentration of each of these substances varies with a person’s , and .

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.