It is completely normal to get results that do not support the hypothesis.
If a scientist encounters this, he/she should refine (change) the hypothesis and perform the experiment again.
Hope this helps!
The correct answer is helper T cells.
<span>The helper T cells are one of the main cells of the adaptive immune system. Their role is to help the activity of other immune cells by releasing T cell cytokines and they are required for almost all adaptive immune responses. The helper T cells activate B cells to secrete antibodies, stimulate macrophages to destroy ingested pathogens, and help in activation of cytotoxic T cells to kill infected target cells.</span>
Deletion is the correct choice
Hello.
Water is necessare because it leads to <span>Photosynthesis that lets plants grow.
Have a nice day </span>
Since chemical spills are very harmful to aquatic/land life for both plants and animals, plants probably wouldn't grow back and animals could be mutated or even killed, decreasing the population of that species. A volcano eruption, can be both good and bad, since a volcano can kill animals and plants, but ash from a volcano is extremely fertile, so plants can regrow, which in turn brings animals back so they can feed on those plants.