Who discovered the human blood groups?

As a small change in a person's dna can cause a genetic disorder

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.

Which greenhouse gas is emitted when burn fossil fuels for energy? a. nitrogen b. oxygen c. carbon dioxide d. helium