Explanation:
Oxygen and nutrients from food must be absorbed into the bloodstream to be delivered to cells for respiration. Waste materials such as carbon dioxide must be removed from cells into the bloodstream. Tissues contain capillary networks to allow these exchanges to occur at a cellular level.
Answer:
(1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
Explanation:
During photosynthesis, the energy from sunlight is used to split water molecules. The thing that happens to the hydrogen ions that are split from the water molecules is that A. they build up in the thylakoid.