Question

Sometimes a single-stranded molecule of RNA is able to fold back on itself because the nucleotide sequence on one part of the RNA is complementary to another part. This sequence motif directly results in a:

Group of answer choices

transcription factor binding site

RNA polymerase

hairpin-shaped structure

membrane protein

A large number of new mutations occuring in an animal genome every generation would be acceptable if:

Group of answer choices

there were good DNA repair mechanisms

most of the genome were noncoding DNA, so few mutations would affect proteins

there were good protein repair mechanisms

most of the mutations occurred in germ cells, rather than somatic cells

Answer 1

Q. Sometimes a single-stranded molecule of RNA is able to fold back on itself because the nucleotide sequence on one part of the RNA is complementary to another part. This sequence motif directly results in a:

Ans. The correct option is hairpin-shaped structure.

→ unique region complementary regions

Hairpin-shaped structure is formed in a RNA molecule that has two regions that are complementary to each other and are separated by a region that is unique. Due to this the regions that are complementary to each other form base pairing resulting in the formation of hairpin loop structure.

Q. A large number of new mutations occurring in an animal genome every generation would be acceptable if:

Ans. The correct answer is most of the genome were noncoding DNA, so few mutations would affect proteins.

If most of the genome were noncoding DNA, then the new mutation will be most probably within the noncoding region of the genome. The noncoding region does not code for protein so few mutations would affect proteins.

For example, mutation within the repetitive DNA segment (noncoding DNA) does not result in any disorder or fault in protein as they don’t code for any protein. Similarly, mutation occurring in the genome would be acceptable only if it occurs within the noncoding DNA.

All other options are incorrect:

If DNA repair is good and a large number of mutation occur within the coding region of genome, then it is possible that most of the mutation will be removed but few mutations will be left which will enough to aflter the protein.

There is no protein repair mechanism that can repair the translated protein only unfolded or misfolded proteins can be repaired to the normal form.

If most of the mutation occur in germ cells it is obvious that it will be transferred and most of the mutation will affect the protein.