Answer options:
- extraction and observation of DNA
- identification of ribose and deoxyribose
- recognition of RNA as DNA’s messenger
- construction of an accurate DNA model
Answer:
- identification of ribose and deoxyribose
Explanation:
Phoebus Levene was an American biochemist who studied the structure of DNA and RNA. He was able to isolate the sugars (ribose and deoxyribose) from the nucleic acids, which are an important part of their structure.
He also determined how the nucleic acid components combine to form the nucleotides, the basic building blocks of nucleic acids, and how the nucleotides combine in chains to form the polymer.
Explanation:
For any enthalpy change in a chemical reaction, (exothermic/endothermic), the activation energy must be reached so as to break the strong chemical bonds between the reactant molecules.
Answer: Bacterial cells can be genetically modified so that they have the gene for producing human insulin. As these modified bacteria grow, they produce human insulin.
Explanation:
