Aprotein is a chain of linked smaller molecules called

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

Which particle controls what element an atom is?

If a force of 40 newtons moves a cart a distance of 9 meters, the work done is nm. if the same force moves the same cart three times that distance, the work done is nm.