Question

question 7 of 25
why was using reverse transcriptase necessary for finding a way to make
artificial insulin?
a. scientists already knew the base sequence for the insulin gene.
b. insulin is made of a chain of nucleic acids.
c. scientists had to convert information from amino acids to nucleic
acids.
d. dna polymerase is the molecule that builds insulin.

Explanation:

Insulin is a protein (made of amino acids). To make artificial insulin using genetic engineering, scientists needed the DNA (nucleic acid) sequence for the insulin gene. Reverse transcriptase is used to make DNA (complementary DNA or cDNA) from mRNA. If scientists knew the amino acid sequence of insulin (from protein analysis), they could figure out the mRNA sequence (using the genetic code) and then use reverse transcriptase (which makes DNA from RNA) to get the DNA (nucleic acid) for the insulin gene. So they had to convert information from amino acids (protein) to nucleic acids (DNA).

• Option A: If scientists already knew the base sequence for the insulin gene, reverse transcriptase might not be the main need (depending on source, but the key is the conversion process as in C).
• Option B: Insulin is a protein (amino - acid chain), not nucleic - acid chain.
• Option D: DNA polymerase synthesizes DNA from a DNA template (in DNA replication etc.), not for building insulin. Insulin is built by ribosomes translating mRNA (after transcription from DNA).

Answer:

C. Scientists had to convert information from amino acids to nucleic acids.