Question

1. Which repair mechanism is most likely affected if the enzyme DNA glycosylase is not functioning properly?

photoreactivation repair

base excision repair

SOS repair

double-strand break repair

nucleotide excision repair

2.

In bacteria and eukaryotes, a mutation is when ________.

In bacteria and eukaryotes, a mutation is when ________.

A.the nucleotide sequence in an mRNA molecule is directly changed

B.the nucleotide sequence in a DNA molecule is directly changed

C.the amino acid sequence in a protein molecule is directly changed

D, DNA is unable to be replicated

E. the expression of a gene changes without the DNA sequence being changed

3.

A mutation that changes an amino acid-coding codon to a stop codon is classified as what kind of codon?

A mutation that changes an amino acid-coding codon to a stop codon is classified as what kind of codon?

A.silent

B.neutral

C.conditional

D.nonsense

E.missense

4.

Germ cell mutations ________.

Germ cell mutations ________.

A.affect somatic cell function in the current generation

B.are usually found in every cell of the next generation

C.are the cause of testicular cancer

D.are of no consequence to the next generation

E. are only seen in females

Answer 1

1. The repair mechanism most likely affected, if the DNA glycosylase not functioning properly is Option B. BASE EXCISION REPAIR. As in this repair mechanism, the enzyme DNA glycosylase cleaves the N- glycosylic bonds liberating the altered base and generating an apurinic or an apyrimidinic site.

2. In bacteria and eukaryotes, mutation is Option B. THE NUCLEOTIDE SEQUENCE IN A DNA MOLECULE IS DIRECTLY CHANGED.

3. A mutation that changes an amino acid-coding codon to a stop codon is classified as Option D. NONSENSE MUTATION.

4. Germ cell mutations Option B.are usually found in every cell of the next generation. As germ cell mutation refers to any detectable variation within germ cells i.e., sperm and ovum. Mutations in these cells can be passed on to offspring, when either a mutated sperm or oocyte come together to form a zygote. So every cell of the next generation will have the same mutation.