Pls help ASAP I need a good grade

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.

What is the most abundant vertebrate on earth?