D)Oxygen diffuses from alveolar sacs to blood in capillaries
Answer:
Viruses and bacteria helps to build up our immune system, specifically our adaptive immune response such that we will be able to eliminate such pathogens when our body comes into contact with them. This builds up the resilience of our immune system over time, similar to how vaccines work.
Chemical<span> reactions like the one above contain two parts: The reactants and the products. 2. Products—the substances that are produced by the reaction. B. Energy in Reactions—energy is </span>released or absorbed whenever chemical bonds form or are broken<span>. :)</span>
