The oxygen used by animals and plants during cellular respiration came from where

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?

Wich level of organization includes all the other levels or organizations

What are some of the immune functions of the lymphatic system? a. cleaning red blood cells from the blood and creating lymph fluids b.transporting lymph to the tissues and creating lymph fluids c.removing infectious agents and making white blood cells d.making red blood cells and removing infectious agents