<span>digestive enzymes
metabolic enzymes
food enzymes</span>
A primary key is a special relational database table column (or combination of columns) designated to uniquely identify all table records. A primary key's main features are: It must contain a unique value for each row of data. It cannot contain null values.
They would burst, as water moves from the hypotonic to hypertonic substances. The red blood cells are hypertonic. They would burst as a result of cytolysis.