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:
It corresponds to a leaf tissue.
Explanation:
The composition of the leaf tissue, which absorbs sunlight, is observed in the process of photosynthesis. The epidermis, parenchyma, stoma, among other structures are observed.
When humans farm large plantation of one cash crop, they reduce the biodiversity of the region because they reduce the genetic diversity of the species in the environment. A reduction in genetic diversity means that the genetic variability of the species is reduced hence there are fewer sub-species in the environment. This ultimately reduces the biodiversity of the ecosystem - which is the variability among all the living organisms in the environment.
