Deck 49: Genomes and Nucleic Acid Alterations

Question 1

On average,how much of a gene sequence is removed as introns,leaving the exons to be spliced together and translated into protein?

A) 100%
B) 95%
C) 50%
D) 1%

Answer 1

95%

Question 2

Polymorphic DNA sequences that are short tandem repeats 1 to 13 base pairs in length are referred to as:

A) microsatellites.
B) minisatellite DNA.
C) long tandem repeats.
D) transposable elements.

Answer 2

microsatellites.

Question 3

In the following sequences,the normal amino acid sequence is given first followed by the sequence that is produced by a sequence alteration.Identify the type of sequence alteration that most likely causes the altered amino acid sequence. Normal Sequence: Phe-Asn-Pro-Thr-Arg
Mutated Sequence: Phe-His-Pro-Thr-Arg
What type of sequence alteration most likely caused the mutation?

A) Indel
B) Missense
C) Nonsense
D) There is no alteration.

Answer 3

Missense

Question 4

Which one of the following is a similarity between bacterial and human genomes?

A) Number of chromosomes
B) Structure of chromosomes
C) Number of genes
D) Presence of double-stranded DNA

Question 5

If you were interested in studying plasmid structure,which one of the following cell types would be appropriate for you to examine?

A) Human cells
B) Fungal cells
C) Bacterial cells
D) All cell types

Question 6

An example of epigenetic variation that affects gene expression would be:

A) heteroplasmy.
B) chromosomal translocation.
C) copy number alteration.
D) histone modifications.

Question 7

Copy number variants comprise approximately what percent of the human genome?

A) 75%
B) 50%
C) 10%
D) 0.5%

Question 8

Which one of the following statements regarding the human genome below is correct?

A) Mobile genetic elements (transposons)comprise almost half of the human genome.
B) An intron is located within a transposon segment of a chromosome.
C) Genes that contain instructions for making proteins are located in transposons.
D) Unique sequences that code for protein make up only 10% of the human genome.

Question 9

In the following sequences,the normal amino acid sequence is given first followed by a sequence that is produced by a sequence alteration.Identify the type of sequence alteration that most likely causes the altered amino acid sequence. Normal Sequence: Phe-Asn-Pro-Thr-Arg
Mutated Sequence: Phe-Asn-Pro
What type of sequence alteration most likely caused the mutation?

A) Indel
B) Missense
C) Nonsense
D) There is no alteration.

Question 10

The major difference between single nucleotide variants (SNVs)and copy number variants (CNVs)is that:

A) SNVs are duplicated in tandem and involve complex gains or losses of homologous sequences,whereas CNVs involve simple sequence changes.
B) CNVs occur in stretches of DNA ranging from 100 to millions of bases in size,whereas SNVs involve single base changes.
C) SNVs are always associated with disease,whereas CNVs are not.
D) SNVs are involved in gene amplification by producing more than two functional genes in a genome.

Question 11

A single nucleotide variant (SNV)that produces a misplaced termination codon in a polypeptide chain is called a:

A) missense variant.
B) transposon.
C) copy number variant.
D) nonsense variant.

Question 12

A virus does not need as much nucleic acid for the production of protein as bacteria do because:

A) viruses use the DNA of the cells that they infect to produce protein.
B) viruses contain high sequence variation.
C) there are no introns in the viral genome.
D) it uses plasmids to synthesize protein instead of DNA.

Question 13

Polymorphic repeated DNA sequences that are sometimes referred to as minisatellite sequences and are between 14 and 500 base pairs in length are called:

A) transposons.
B) a variable number of tandem repeats.
C) a restriction endonuclease.
D) short tandem repeats.

Question 14

Approximately what percentage of genomic DNA is required to maintain the structure of chromosomes as centromeres and telomeres?

A) 75%
B) 50%
C) 20%
D) 2%

Question 15

A single nucleotide variant that produces a misplaced termination codon in a polypeptide chain results in:

A) a frameshift mutation.
B) premature polypeptide chain termination.
C) chromosomal translocation.
D) a trinucleotide repeat.