What is used as a main source of energy for a cell?

The image below shows a common blood pressure gauge. what does this device do? a. measures the level of oxygen present in the blood b. measures the pressure of blood when the lungs expand and compress c. measures the electrical activity of the heart d. measures the pressure of blood when the heart contracts and relaxes

Explain how sequences of amino acids in proteins can be used to reveal relationships among organisms.

The term facultative anaerobe refers to an organism that