Molecular Genetics Short Quizizz Review from test

Which of the following facts did Hershey and Chase make use of in trying to determine whether DNA or protein is the genetic material?

• DNA contains sulfur, whereas protein does not.

• DNA contains purines, whereas protein includes pyrimidines.

• DNA contains phosphorus, whereas protein does not.

• DNA contains nitrogen, whereas protein does not.

Cytosine makes up 40% of the nucleotides in a sample of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine?

• 10%

• 20%

• 40%

• 80%

A virus consisting of a single strand of RNA, which is reverse transcribed into complementary DNA, is referred to as a ________.

• bacteriophage

• retrovirus

• prion

• virulent phage

Which of the following processes do normal proto-oncogenes typically exhibit?

• They normally suppress tumor growth.

• They enhance tumor growth.

• They stimulate normal cell growth and division.

• They are underexpressed in cancer cells.

Humans have 23 pairs of chromosomes, and chimps have 24 pairs of chromosomes. What is the most likely explanation for these differences in human and chimp genomes?

• At some point in evolution, human and chimp ancestors reproduced with each other.

• In the evolution of chimps, new adaptations resulted from additional chromosomal material.

• The common ancestor of humans and chimps had 24 pairs of chromosomes. During human evolution, two human chromosomes fused end to end.

• Errors in mitosis resulted in an additional pair of chromosomes in chimps.

Which of the following information or processes does gene therapy require?

• the ability to introduce the normal allele into the patient

• the knowledge and availability of the defective gene but not the normal allele

• the ability to express the introduced gene at any time in the tissue site within the patient

• the ability to introduce a defective allele into a patient

For a repressible operon to be transcribed, which of the following conditions must occur?

• A corepressor must be present.

• RNA polymerase and the active repressor must be present.

• RNA polymerase must bind to the promoter, and the repressor must be inactive.

• RNA polymerase must not occupy the promoter, and the repressor must be inactive

Liver cells differ from skin cells mainly because they...

• have unique ribosomes.

• use different genetic codes.

• contain different genes.

• express different genes.

What is Cas9 and what does it do?

• a protein enzyme that cuts both strands of DNA at sites specified by an RNA guide

• a DNA sequence that binds the Cas9 protein

• an RNA molecule that binds to target DNA via complementary base pairing

• a viral protein that disrupts bacterial membranes

How many amino acids could be coded using the sequence 5'AUGCCCGUA3'

• 1

• 2

• 3

• 4