DNA Mutations — Unit test Answers

0 verified answers2 views
1
Free Preview

James is working with the lac operon of Escherichia coli (E. coli). He places the bacteria on a plate of growth media. Based on the current understanding of this operon, which hypothesis would be useful for James to test?

Question illustration
A
Addition of allolactose (inducer) to the bacterial growth media should increase the speed at which the bacteria metabolize the sugar lactose.
B
Removal of the RNA polymerase molecule should increase the amount of bacterial growth on the plate.
C
Decreasing the amount of allolactose (inducer) in the bacterial growth media should increase the rate of bacterial growth.
D
Increasing the rate at which RNA polymerase acts will inhibit bacterial growth.
2
Free Preview

What must occur for protein translation to begin?

A
A water molecule must be added to the protein chain.
B
A peptide bond must form between subunits of mRNA.
C
The amino acid Cys must be picked up by tRNA.
D
The codon AUG must be identified.
3

How many genes make up the human genome?

A
four: adenine, thymine, guanine, and cytosine
B
23 pairs of genes
C
20,000–25,000 genes
D
3 billion genes
4

Maria is concerned because she has been exposed to a small amount of radiation during an X-ray. What is her doctor most likely to tell her?

A
Radiations from X-rays is not a mutagen.
B
Mutagens have no effect on the body unless you have inherited them.
C
Small amounts of a mutagen often do not have an effect on health.
D
Severe mutations are usually caused by small amounts of a mutagen.
5

Which represents a strand of RNA bases?

A
CAAGGTCTC
B
AGGTTCACA
C
CAAGGUCUC
D
TGGAACTCA
6

Which best summarizes the process of protein synthesis?

A
RNA instructs DNA to make proteins.
B
DNA unzips, resulting in the formation of two protein molecules.
C
RNA moves the DNA code to the ribosomes for protein synthesis.
D
DNA makes proteins in the nucleus.
7

What was Friedrich Miescher's contribution to the discovery of the genetic code?

A
He created the first photograph of the structure of DNA.
B
He discovered how the DNA bases pair together.
C
He created the first accurate model of DNA's structure.
D
He extracted and observed DNA from white blood cells.
8

Which is a frameshift mutation?

A
substitution
B
nonsense
C
silent
D
deletion
9

Which of the following correctly organizes these genetic terms in order from smallest to largest?

A
chromosome, gene, nucleotide, DNA molecule
B
nucleotide, gene, DNA molecule, chromosome
C
DNA molecule, nucleotide, gene, chromosome
D
DNA molecule, nucleotide, chromosome, gene
10

Which best matches a type of genetic material with its description?

A
Nucleotides form a helical structure that is called a gene.
B
Genes combine to form structures called nucleotides.
C
Chromosomes create genes.
D
DNA is located in the nucleus.
11

Which describes something that occurs during translation?

A
A DNA template is used to create an mRNA strand.
B
A tRNA template is used to create a DNA strand.
C
A tRNA template is used to create an mRNA strand.
D
An mRNA template is used to create an amino acid chain.
12

Which is an arrangement of genes consisting of an operator, a promoter, and a repressor?

A
RNA polymerase
B
anticodon
C
codon
D
operon
13

Which of these is the primary site of protein synthesis?

A
mitochondria
B
cytoplasm
C
nucleus
D
ribosomes
14

A forensic scientist is trying to find out the number of adenine bases in the DNA sample that he obtained from a crime scene.What can he assume about the number of adenine?

A
The number of adenine bases will be equal to the number of guanine bases.
B
The number of adenine bases will be equal to the total of all the other bases.
C
The number of adenine bases will be equal to the number of thymine bases.
D
The number of adenine bases will be half of the number of cytosine bases.
15

Many different types of mutations can occur within the body. Cystic fibrosis is a genetic disorder that is caused by different mutations within the CFTR gene. One mutation in the CFTR gene that leads to cystic fibrosis causes translation to end earlier in the gene sequence. Which type of mutation causes this translation error that leads to cystic fibrosis?

A
silent
B
missense
C
nonsense
D
deletion
16

What can a person do to limit exposure to X-rays?

A
wear sunblock
B
avoid cigarette smoke
C
wear a protective lead vest
D
avoid chemicals
17

A point mutation changes the DNA sequence CGA to CGT, but the same protein is still produced. Which point mutation occurred?

A
nonsense
B
missense
C
silent
D
frameshift
18

What was Marshall Nirenberg and Heinrich Matthaei’s contribution to our current understanding of the genetic code?

A
discovery of codons
B
discovery and extraction of DNA
C
creation of a model of DNA
D
creation of Photo 51
19

Which occurs during transcription?

A
DNA is copied to create a second DNA strand.
B
mRNA codons and tRNA anticodons assemble amino acids.
C
DNA is unzipped with the aid of DNA polymerase.
D
mRNA is synthesized from a strand of DNA.
20

According to Chargaff's rule, base pairing in DNA should resemble which of the following?

A
A = T; C = G
B
A = C; T = G
C
A = G; T = U
D
A = U; C = G

Did you find these answers helpful?