Molecules Tab
What are the building blocks of macromolécules

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

What are some natural processes that represent physical and chemical changes?

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins