15 POINTS PLS HELP ME HERE! THANK YOU!

Which are forms of nitrogen that are usable by humans

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.

How do the evolutionary chart and the video support the claim that all living things are made up of cells?