The particle that determines the identity of an element is the
a. proton.
b. photon.
c. neutron.
d. electron.

How many species of living things are alive on earth today? more than 1,000,000 none of these answers are correct 100-500 1,000 –500,000 o 500,000 -1,000,000

What is usually (but not always) related to the metabolic processes of living organisms in its organic form?

Nephrons, the functional unit of kidneys, are responsible for formation of urine. the sentences describe situations that are the result of problems in the urine formation process. for the nephron shown below, match each situation to the step in the urine formation process where the problem lies.