The answer is amyloid beta. They clump together and form plaques. The formed plaque can block signals transmitted from one cell to another cell. In addition, the plaque can cause swelling, especially in the area where it is formed. It can also digest the disabled cells. This type of plaque is very common among patients with Alzheimer's Disease.
In parasitism, one organism harms another organism (the host). An example would be fleas living in cats/dogs; they feed on their blood.
Therefore the answer is A is harmed, and B is helped.
Answer:
In mammals, oxygen is carried through the red blood cells called hemoglobin. The reason is that the oxygen is very important for the cell for releasing energy. This energy is used by the cell in different processes.
2) These adaptations are adapted by the organisms in order to perform different functions. In slow twitch skeletal muscles having high number of mitochondria because it requires more energy while fast twitch skeletal muscles contains less amount of mitochondria due to low requirements of energy. These characteristics are adapted according to the performance of the body parts.
I am pretty sure that the thing which most likely happen to plants if they did not have a waxy outer coating is being revealed by the last option D. They would be harmed by insects and UV radiation. Every plant has to be protected by membrane so that it would be able to deal with drought small invaders and other external forces.