NEW
Font size
S
M
L
XL
WorksheetsExam 3 Practice
Total questions: 55
Worksheet time: 28mins
Name
Class
Date
1.
DNA is built from two parallel strands of repeating units called
a)
chromosomes
b)
alleles
c)
allozymes
d)
nucleotides
e)
nucleosomes
2.
Which of the following is one of the three main components of a nucleotide?
a)
an amino acid
b)
a phospholipid bilayer
c)
glucose
d)
a phosphate group
e)
a benzene ring
3.
What is deoxyribose?
a)
A chain of DNA
b)
a sugar
c)
a salt
d)
a phosphate group
e)
an enzyme
4.
What forms the rungs of a DNA "ladder"?
a)
The sugar, deoxyribose
b)
A phosphate group
c)
A pair of nitrogenous bases
d)
A sugar-phosphate pair
e)
histone proteins
5.
How many base pairs are in a typical genome of a human?
a)
46
b)
48
c)
3.2 billion
d)
3.2 million
e)
2000
6.
This is the term for a single "bead" of compacted DNA plus proteins.
a)
histone
b)
nucleosome
c)
nucleotide
d)
chromatin
e)
deoxyribose
7.
What is chromatin fiber?
a)
The compact form of DNA.
b)
The chemical that moves chromosomes during replication.
c)
The building block of DNA
d)
The building block of RNA
e)
An enzyme necessary for DNA replication.
8.
What is the first step of DNA replication?
a)
DNA molecules separate into different alleles
b)
DNA polymerase builds a new string of nucleotides, using the template strand
c)
DNA is transported into the cytoplasm
d)
DNA is cut into smaller pieces, called genets.
e)
Proteins bind at the origin of replication.
9.
What is the function of DNA polymerase?
a)
It builds a new molecule of DNA using one strand as a template.
b)
It unzips the DNA molecule, so the template can be read.
c)
It makes an RNA copy of DNA for gene expression.
d)
It builds nucleotides from sugars, phosphate groups, and bases.
e)
It bundles DNA into chromosomes.
10.
What is meant by "semiconservative" replication?
a)
Cells recycle (conserve) nucleotides from old DNA molecules to make new DNA.
b)
Cells recycle (conserve) nucleotides from old RNA molecules to make new DNA.
c)
To save resources, cells only copy the parts of DNA that have been used in the life of the cell.
d)
After being used to make a new DNA molecule, the original DNA molecule reforms.
e)
Each new DNA double helix contains one old strand and one new strand.
11.
This is a lab technique used to copy DNA for research.
a)
PCR
b)
PERV
c)
CRISPR
d)
Cas9
e)
Dnase
12.
Choose the correct complementary strand for this template strand of DNA: ACG CAT GTG
a)
CAT ACG TGT
b)
ACG CAT GTG
c)
TGC GTA CAC
d)
GTG TAC GCA
e)
CAT CAT CAT
13.
In a DNA double helix, ______ _______ bonds connect each nucleotide along a single strand, while ______ _______ bonds connect the two strands together.
a)
weak covalent; strong hydrogen
b)
strong hydrogen; weak covalent
c)
strong covalent; weak hydrogen
d)
weak hydrogen; strong covalent
e)
weak covalent; weak hydrogen
14.
Which of the following is the best description of PCR?
a)
an artificial way to correct mutations in a gene
b)
a quick method of sequencing the nucleotides in a DNA molecule
c)
a genetic disorder preventing the proper function of DNA polymerase.
d)
an artificial way to edit the genome of an organism
e)
fast, artificial DNA replication
15.
Which of the following is the correct order of compaction from least compact to most compact?
a)
naked DNA, beads-on-a-string, nucleosome, chromatin fiber, chromosome
b)
naked DNA, chromatin fiber, nucleosome, beads-on-a-string, chromosome
c)
chromosome, chromatin fiber, beads-on-a-string, nucleosome, naked DNA
d)
naked DNA, nucleosome, beads-on-a-string, chromatin fiber, chromosome
e)
chromosome, naked DNA, nucleosome, beads-on-a-string, chromatin fiber
16.
The CRISPR method for genome editing uses a system made up of what molecules?
a)
two RNA molecules plus Cas9 proteins
b)
proteins and Cas9 RNA molecules
c)
one DNA molecule and one RNA molecule
d)
RNA polymerase and Cas9 proteins
e)
two DNA molecules plus Cas9 proteins
17.
Which of the following pairs would you expect to have the most similar DNA sequences?
a)
two members of different kingdoms
b)
two members of the same genus but different species
c)
two members of the same kingdom but different genera
d)
two members of the same family but different species
e)
two members of the same species
18.
Do different alleles of a gene have the same DNA sequence or different DNA sequences?
a)
same
b)
different
19.
What must be broken before replication can begin?
a)
the cell membrane
b)
interphase
c)
hydrogen bonds
d)
covalent bonds
e)
phosphate groups
20.
Why is PCR referred to as DNA amplification?
a)
Because the process amplifies the sound of DNA replication.
b)
Because the process increases the number of copies of DNA
c)
Because the DNA template strand becomes larger during replication
d)
Because the cell swells during DNA replication
e)
Because it makes it possible for scientists to read the sequence.
21.
During PCR, what causes the DNA strands to separate?
a)
DNA polymerase
b)
Water and oil
c)
heat
d)
RNA polymerase
e)
Cas9 proteins
22.
The process by which DNA is used to synthesize a complementary strand of RNA is called
a)
transcription
b)
translation
c)
polymerization
d)
RNA replication
e)
semiconservative replication
23.
The binding site in DNA, upstream of the coding region, where RNA polymerase attaches at the beginning of transcription, is called the
a)
operator
b)
promoter
c)
activator
d)
rRNA
e)
codon
24.
Transcription stops when RNA polymerase encounters a special region of template DNA known as the
a)
repressor
b)
detritivore
c)
codon
d)
terminator
e)
anticodon
25.
A key difference between DNA and RNA is that RNA
a)
A: is single-stranded
b)
B: uses uracil in place of thymine
c)
C: uses ribose in place of deoxyribose
d)
A, B, and C are true
e)
None of these (A, B, C) are true
26.
What term is used for the expressed regions in an RNA transcript that are retained after non-coding regions are removed?
a)
introns
b)
exons
c)
uracils
d)
mutations
e)
promoters
27.
In eukaryotes, RNA is modified before it leaves the nucleus as a mature mRNA molecule. Specifically, non-coding regions are spliced out of the RNA. These non-coding regions are called
a)
exons
b)
uracils
c)
introns
d)
UTRs
e)
promoters
28.
The process by which one gene can encode many different proteins, depending on which exons are removed and which are left in the mature mRNA, is due to
a)
gene expression
b)
post-transcriptional modifications
c)
gene emoting
d)
alternative genetics
e)
exonification
29.
The process by which mRNA is used to synthesize protein is called
a)
transcription
b)
translation
c)
polymerization
d)
RNA replication
e)
semiconservative replication
30.
These cytoplasmic structures help translate information from the language of mRNA (nitrogenous bases) to the language of proteins (amino acids).
a)
ribosomes
b)
cytoskeleton
c)
mitochondria
d)
codons
e)
DNA polymerase
31.
The molecules responsible for delivering amino acids to mRNA during protein synthesis are called
a)
ribosomes
b)
ligase
c)
uracil
d)
rRNA
e)
tRNA
32.
The three-nucleotide region of mRNA that codes for an amino acid is called a(n)
a)
operator
b)
promoter
c)
exon
d)
codon
e)
anticodon
33.
The sequence for the start codon is ____, while the sequence for the stop codons are ___, ___, and ___.
a)
AUG; UAA, UAG, and UGA
b)
CAT; GAA, GAT, and GAG
c)
ATG; TAA, TAG, and TGA
d)
UAA; UAG, UAC, and UAU.
34.
True or False. Some amino acids can be coded for by more than one codon; in fact, approximately 64 mRNA codons are used to code for the 20 amino acids found in living things.
a)
True.
b)
False.
35.
Nearly every organism on Earth uses the same genetic code. Therefore, the code is said to be.
a)
redundant
b)
unambiguous
c)
ambiguous
d)
universal.
36.
What does gene regulation allow a cell to do?
a)
It enables the cell to change which gene and how much a gene is expressed
b)
It allows a cell to compensate for mutations or deficiencies in its DNA
c)
It allows a cell to reproduce more rapidly and effectively
d)
It allows a cell to change how fast it replicates its DNA.
37.
Gene expression can change in response to internal signals (from inside the body) or external cues in the environment. When the rate of gene expression is slowed down, it is said to be ___________________.
a)
modulated
b)
repressed
c)
up-regulated
d)
down-regulated.
38.
Differential survival and reproduction among individuals of a population that vary in details of shared, inherited traits is referred to as
a)
ecological adaptation
b)
biogeography
c)
natural selection
d)
fitness
e)
comparative biology
39.
The ultimate source of new alleles in populations is
a)
genetic drift
b)
gene flow
c)
inheritance
d)
mutation
e)
natural selection
40.
The collection of all of the genes in one population is referred to as the
a)
gene pool
b)
genotype
c)
phenotype
d)
genome
e)
gene library
41.
Which of the following could bring about a change in the allele frequencies (i.e., evolution) in a population?
a)
mutation
b)
gene flow
c)
genetic drift
d)
natural selection
e)
all of these
42.
The mode of selection in which traits at one end of a range of variation become more common is called
a)
stabilizing selection
b)
directional selection
c)
disruptive selection
d)
artificial selection
e)
driving selection.
43.
The mode of selection that favors an intermediate phenotype and eliminates extreme forms is called
a)
stabilizing selection
b)
directional selection
c)
disruptive selection
d)
artificial selection
e)
driving selection.
44.
The word “evolution” in biology essentially means
a)
survival
b)
progress
c)
change over time
d)
mutation
e)
speciation
45.
The study of patterns in the geographic distribution of species is called
a)
diversity
b)
biogeography
c)
ecology
d)
natural history
e)
environmentalism
46.
The study of the body plans and structures among groups of organisms is called
a)
embryology
b)
molecular archeology
c)
evolution
d)
comparative morphology
e)
composition
47.
Some organisms have structures with no apparent function, although they resemble functional structures in other organisms. For example, snakes have the remnants of bones for legs (but no legs), and humans have a tailbone (but no tail). Such structures are referred to as
a)
trace fossils
b)
vestigial
c)
artificial
d)
variable
e)
mutations
48.
The similarity between the bones in the arm of a human and the bones in the wing of a bat are due to their inheritance from a common ancestor. Such structures are said to be
a)
analogous
b)
homologous
c)
mutations
d)
uniformitarity
e)
coevolutionary
49.
The four different blood types (A, B, AB, and O) are determined by three different alleles for a single gene. Which of the following terms best describes this occurrence of multiple alleles in a population?
a)
phenotypic plasticity
b)
independent assortment
c)
polymorphism
d)
dimorphism
e)
population genetics
50.
In a population of 1000 penguins, 350 are heterozygous (Aa) for a particular gene. What is the frequency of the heterozygotes?
a)
0.35
b)
0.7
c)
0.65
d)
0.5
e)
Need additional information to determine
51.
If the population consists of 1 million diploid individuals with genotypes AA, Aa, and aa, what is the total number of alleles in the population?
a)
1 million
b)
2 million
c)
~333 thousand
d)
500000
e)
Need additional information to determine
52.
A trait that enhances an individual’s ability to survive and reproduce in a particular environment is called
a)
phenotype
b)
genotype
c)
fitness trait
d)
adaptive trait
e)
reproductive trait
53.
Birds and insects both have wings for flying through the air. In this example, wings are
a)
a vestigial trait
b)
a homologous trait
c)
an adaptive trait
d)
an artificially selected trait
54.
Which of the following is NOT evidence for evolution by natural selection?
a)
During the Industrial Revolution, black soot from coal-burning smokestacks covered surfaces, including trees. Over generations, the population of mostly white-colored peppered moths became mostly dark-colored peppered moths
b)
After Doug completed a course of the antibiotic methicillin for an infection, he was hospitalized with MRSA (methicillin-resistant S. aureus) infection
c)
The agricultural industry has developed varieties of tomatoes with characteristics such as large size, uniform red coloration, and roundness
d)
Many farmers view morning glories as a weed. Two decades ago, the herbicide Roundup could be used to kill them. Today, the morning glories survive despite being sprayed with Roundup
55.
Which of the following illustrates evolution by natural selection?
a)
Shonda grew up in the hot climate of Louisiana. Five years ago, she moved to the Colorado mountains and has gotten used to the cold weather
b)
Many people living in the high-altitude, oxygen-poor region of Tibet have a gene mutation that increases their blood oxygen supply
c)
Ten years ago, Jacinda could run only 0.5 kilometers. She has been training for years and this year successfully ran a marathon.
Reset
