| A | B |
|---|
| excitability | ability of a cell to react to a stimulus |
| irritability | ability of a cell to react to a stimulus |
| conductivity | ability of a cell to transmit an impulse |
| contractility | ability of a muscle cell to shorten |
| ingestion | taking in of food |
| metabolism | all of the physical and chemical processes which keep us alive |
| digestion | breaking down of food |
| cell respiration | food and oxygen combine to produce energy |
| excretion | removal of wastes |
| secretion | production of substances other than wastes |
