The answer is negative controls. These are groups where no phenomenon is probable. They ensure that there is no effect when there should be no effect. Where there are only two possible outcomes, e.g. positive or negative, if the treatment group and the negative control both produce a negative result, it can be concluded that the treatment had no effect. If the negative control group and the treatment group both yield a positive result, it can be inferred that a puzzling variable is involved in the occurrence under study, and the positive results are not only due to the treatment. In other examples, outcomes might be measured as lengths, times, percentages, and so forth.
Answer:
Stabilizing selection
Explanation:
Stabilizing selection is the most common form of natural selection that is not easy to notice in a population as the change is less drastic. It occurs when average or intermediate phenotypes of a trait in a population are favored, while the extreme phenotypes of that trait are not favored by the forces of natural selection. Over time, intermediate or non-extreme traits become more common in the population, while extreme traits become less common.
Answer:
Explanation: Bacteria and archaea are prokaryotes, while all other living organisms — protists, plants, animals and fungi — are eukaryotes. ... The vast majority of protists are unicellular or form colonies consisting of one or a couple of distinct kinds of cells, according to Simpson.
No, polar bears does not migrate.
