In the image below which letters represent facilitated diffusion?

Why is it important that fibrin is insoluble in water?

How are mutations continually being generated in a population (what are some of the causes of mutatuions? ) explain

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.