I knew this at one point but I forgot it
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: A protein's specific shape determines its function.
Explanation: If the three-dimensional structure of the protein is altered because of a change in the structure of the amino acids, the protein becomes denatured and does not perform its function as expected.
Answer:
Cellular differentiation is the process in which a cell changes from one cell type to another. Usually, the cell changes to a more specialized type. Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types.
It's the nucleus or the nucleolus to be exact which produces rRNA which as a structural component of ribosomes.
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