Answer:
To study objects that are way too small
T cells
The immune response to a transplanted organ consists of both cellular (lymphocyte mediated) and humoral (antibody mediated) mechanisms. Although other cell types are also involved, the T cells are central in the rejection of grafts. The rejection reaction consists of the sensitization stage and the effector stage.
<span>The correct answer is d. Antarctica must have been in a different warmer location in the past. The presence of Glossopteris in Antarctia proves that the continent was located closer to the equator and have since drifted to the south pole. This observation supports the theory of continental drift. </span>
Answer:
17: Mitochondria and Chloroplasts
19: The cell membrane is a double-layered sheet called a lipid bilayer. It affects the content of the cell because it controls what goes in and out of the cell.
Answer:
Hmm.
Explanation:
Measles is so contagious that if one person has it, up to 90% of the people close to that person who are not immune will also become infected. Infected people can spread measles to others from four days before through four days after the rash appears.