Answer: Meselson & Stahl reasoned that these experiments showed that DNA replication was semi-conservative: the DNA strands separate and each makes a copy of itself, so that each daughter molecule comprises one "old" and one "new" strand. The semi-conservative model, in which each strand of DNA serves as a template to make a new, complementary strand, seemed most likely based on DNA's structure. ... From the patterns of DNA labeling they saw, Meselson and Stahl confirmed that DNA is replicated semi-conservatively.
Explanation:
Well, there is only one realistic answer. Option One is when you take the DNA of two different people or creatures and combine them into one organism. Cloning wouldn't prove anything here, "hybridization" is weird - but it doesn't have anything to do with the situation. So only only remaining option is DNA Profiling - also known as DNA Mapping, which shows the DNA structure and order that can be seen the same way in siblings (slightly different of course but it is still the right answer).
Answer:
The correct answer is option 3. "secondary structure".
Explanation:
The secondary structure of polypeptide and proteins refers to the second order of folding, including common structures such as beta sheets, alpha helix, as well as turns and loops. The hydrogen bonds between the oxygen and nitrogen atoms of the peptide bonds are crucial to secondary structures, as these hydrogen bonds form and stabilize the aforementioned common structures.