Answer;
-Gametic Isolation
Explanation;
-Gametic isolation is a type of prezygotic barrier where the gametes (egg and sperm) come into contact, but no fertilization takes place.
-In Gametic isolation is when sperm of one species may not be able to fertilize the eggs of another species. For instance, sperm may not be able to survive in the reproductive tract of females of the other species, or biochemical mechanisms may prevent the sperm from penetrating the membrane surrounding the other species' eggs.
The kingdoms that include both unicellular & multicellular are protist & fungi
Answer:
Mechanical digestion begins in the mouth as the food is chewed. Chemical digestion involves breaking down the food into simpler nutrients that can be used by the cells.
Explanation:
Chemical digestion begins in the mouth when food mixes with saliva. Saliva contains an enzyme (amylase) that begins the breakdown of carbohydrates.