Why are fossils of some cetaceans homologous stuctures?

Are gametes exactly the same? explain why or why not?

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.

Try to answer all questions if possible i will take anything this is worth 21 ! ! 1. what rights do citizen's have in a monarchy? 2. what countries practice monarchy? 3. what is one advantage of a monarchy? 4. what is one disadvantage of a monarchy? 5. what rights do citizen's have in a dictatorship? 6. what countries practice dictatorship? 7. what is one advantage of dictatorship? 8. what is one disadvantage of dictatorship?