- Life Sciences
a chemical messenger produced and released by a cell or a gland in one part of the body of the organism that affect cells in other parts of the organism. In essence, it is a chemical messenger that transports a signal from one cell to another. Only a small amount of hormone is required to alter cell metabolism. Hormones in animals are most often transported in the blood.
the movement of molecules across a membrane against the concentration gradient, from an area of...
cellular respiration that takes place when free oxygen is absent
the instrument that measures the volume of air entering and leaving the lungs.