Answer:
<em><u>A. Neither the subjects nor the researchers can bias the results.</u></em>
Explanation:
As described, a double- blind study is one in which the researcher and his study does not know the person receiving the actual treatment.
Researchers can be bias in their studies as they seek to establish and fine tune results in the way the best favors them. A double-blind study helps to bridge this gap to prevent bias that might be introduced into an experimental set up or while interpreting results.
Rod: night vision
Cone: day vision
They are typically composed of thousands of atoms or more. The most common macromolecules in biochemistry are biopolymers nucleic acids, proteins, carbohydrates and lipids and large non-polymeric molecules such as lipids and macrocycles
These two frog species separate by reduced hybrid viability. In reduced hybrid viability gene of different parent species may interact and impair the hybrid's development while in a reduced hybrid fertility a viable individual is sterile often due to the inability to produce normal gametes in meiosis. Hybrid breakdown; the first generation are viable and fertile, but when they mate the offspring are feeble and sterile.
The third and last option is correct.
Species in the past (referring to dinosaurs) were more massive.
levels where higher in the past, which meant that plants prospered during that time since they had a easy access to food. That contributes to the fact that herbivores could grow bigger because there was more food. Which in turn, increases the size of early carnivores which eat bigger herbivores.
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