Why do scientists only test one independent variable in an experiment?

The chemical form of energy that is useable by the cell to do work

The normal shape of an enzyme is as shown in structure a. if the enzyme’s shape changes to that shown in structure b, what are two consequences of this change?

1. isogamy 1 organisms with gametes of the same size and shape 2. anisogamy organisms with gametes of different sizes and shapes 3. oogamy 2 organisms with gametes of the same shape but different sizes 4. gonads gamete-producing organs in lower plants 5. gametangia gamete-producing organs in animals