<span>1. Pose significant questions that can be investigated empirically.
2. Link research to relevant theory.
3. Use methods that permit direct investigation of the question.
4. The methods used to obtain data and test hypotheses should be benevolent and not malevolent.</span>
People used vaccines to reduce the risk of infection by working with body as defenses to help them so this vaccines develop immunity to disease
I hope that's help:0
Answer:
The monomers of DNA are individual nucleotides: cytosine, guanine, adenine, and thiamine, (A, T, C, G, respectively). Since DNA is a double-stranded molecule, each nucleotide has a match that chemically interacts with it to form nucleotide pairs
Explanation:
Bird skeletons are very delicate, and therefore, difficult to be preserved. The bones of the birds are soft. The small animals are very prone to physicochemical as well as biological decay. This is why the fossil record of bird is incomplete and well-preserved fossils of birds are rare to find, except at a few unusual sites.
Tubes that lead from the heart to the rest bud
