BIOL 1 Final Exam

Question 1

The independent assortment of allele pairs is due to __________________________.

a) the independent segregation of sister chromatid pairs during anaphase I.
b) the independent segregation of homologous chromosome pairs during anaphase I.
c) the independent segregation of homologous chromosome pairs during anaphase II.
d) the independent segregation of non-sister chromatid pairs during anaphase II.

Answer 1

b) the independent segregation of homologous chromosome pairs during anaphase I.

Question 2

An extensive study was conducted on identical twins who were separated at birth. Among other things, the study showed that the individual from each pair who received better nutrition during childhood tended to score higher on standardized intelligence tests. This can best be described as an example of how _____________________.

mutation alters phenotype.
mutation alters genotype.
environment alters genotype.
environment alters phenotype.

Answer 2

environment alters phenotype.

Question 3

If a single gene has 3 or more alternative forms, this is called _________________.

epistasis.
multiple alleles.
blending inheritance.
pleiotropy.

Answer 3

multiple alleles.

Question 4

During his experiments with pea plants, Mendel referred to the trait that was expressed in the F1 or first filial generation as _________________.

independent.
homozygous.
heterozygous.
dominant.

Answer 4

dominant.

Question 5

Let P = purple flowers and p = white, and T = tall plants and t = short. If the uppercase letters represent the dominant alleles, what is the phenotype of a plant with the genotype PpTt?

white flowers, tall
white flowers, short
purple flowers, short
purple flowers, tall

Answer 5

purple flowers, tall

Question 6

An allele for a particular trait that is only expressed in the presence of a second copy of the same allele is called ________________.

dominant.
codominant.
recessive.
incompletely dominant.

Answer 6

recessive.

Question 7

Mendel’s Principle of Independent Assortment states that different pairs of ________________.

alleles segregate independently of each other.
sister chromatids segregate independently of each other.
non-sister chromatids segregate independently of each other.
gametes segregate independently of each other.

Answer 7

alleles segregate independently of each other.

Question 8

The observable outward manifestation of the genes of an individual is referred to as its _________________.

genotype.
phenotype.
genetic map.
blueprint.

Answer 8

phenotype.

Question 9

Three babies were recently mixed up in a hospital. Based on the data in the table above, the couple with blood types A and B are the actual parents of the child with blood type _________________.

AB
O
B
None of these babies could be the child of the couple with blood types A and B.

Answer 9

AB

Question 10

Achondroplasia is caused by an autosomal dominant mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. A person who carries this mutation has shorter limbs than average. Two copies of the mutant gene are invariably fatal before or shortly after birth. If a person with achondroplasia has children a person of average height, what is the probability that both their first child and second child will have achondroplasia?

1/8
1/4
1
1/2

Answer 10

1/4

Question 11

What is the correct sequence for DNA replication in E. coli?

Elongation, termination, initiation.
Initiation, termination, elongation.
Elongation, initiation, termination
Initiation, elongation, termination.

Answer 11

Initiation, elongation, termination.

Question 12

During DNA replication, each new strand begins with a short ______________.

RNA primer.
amino acid primer.
DNA primer.
hydrophilic primer

Answer 12

RNA primer

Question 13

If a mutation produced helicase that was unable to hydrolyze ATP, DNA replication would be

stopped.
unaffected.
speeded up.
more prone to errors

Answer 13

stopped.

Question 14

DNA replication always proceeds by adding new bases to the _________ end of an existing strand.

3’
2’
4’
5’

Answer 14

3’

Question 15

What is the function of a protein kinase?

To remove phosphate groups from proteins.
To phosphorylate GDP to generate GTP.
To cleave membrane phospholipids.
To add phosphate groups onto proteins.

Answer 15

To add phosphate groups onto proteins.

Question 16

The lagging strand is replicated with a series of Okazaki fragments and that is why its synthesis is considered to be ________________.

continuous.
semiconservative
antiparallel.
discontinuous.

Answer 16

discontinuous.

Question 17

When a mixture of live nonvirulent bacteria and dead virulent bacteria was injected into mice, Griffith unexpectedly found that the injected mice died. He explained this result by suggesting that the nonvirulent bacteria are being _______________.

activated.
transcribed.
translated.
transformed.

Answer 17

transformed.

Question 18

If a short sequence of DNA is 5’ AATTGCCGT 3’, its complement is _______________.
3’ TTAACGGCT 5’.
3’ TTAAGCCGA 5’.
3’ TTAACGGCA 5’.
5’ AAAACGCCA 3’

Answer 18

3’ TTAACGGCA 5’.

Question 19

A researcher is working to generate a new cancer drug. Thus far, he has identified a compound that can reduce the size of tumors in the lung. However, in order for the drug to work, the lung tumor has to be small. In addition, the tumor cannot have metastasized (spread to other areas of the body). Furthermore, he knows that the drug acts to prohibit the signaling from one tumor cell to another tumor cell. Given the above information, this new drug prohibits:

synaptic signaling between tumor cells.
endocrine signaling between tumor cells.
paracrine signaling between tumor cells.
autocrine signaling between tumor cells.

Answer 19

paracrine signaling between tumor cells.

Question 20

DNA primase

creates a short DNA primer that is complementary to a DNA template.
creates a short DNA template that is complementary to an RNA primer.
creates a short DNA primer that is complementary to an RNA template.
creates a short RNA primer that is complementary to a DNA template.

Answer 20

creates a short RNA primer that is complementary to a DNA template.

Question 21

If fertilization involves two gametes that contain different alleles of a given gene, the resulting offspring is ______________.

heterozygous.
haploid.
dihybrid.
homozygous.

Answer 21

heterozygous.

Question 22

Of the 23 pairs of human chromosomes, 22 pairs are homologous and are found in both males and females. These are called _________.

autosomes.
recombinant chromosomes.
bivalents.
somatic chromosomes.

Answer 22

autosomes.

Question 23

ABO blood group determination is an example of ________________.

multiple alleles.
incomplete dominance.
pleiotropy.
epistasis.

Answer 23

multiple alleles.

Question 24

Mendel’s Principle of Independent Assortment states that different pairs of ________________.

alleles segregate independently of each other.
gametes segregate independently of each other.
non-sister chromatids segregate independently of each other.
sister chromatids segregate independently of each other.

Answer 24

alleles segregate independently of each other.

Question 25

Individuals that have 2 alleles for most gene loci are best described as _________________.

diploid.
heterozygous.
dihybrid.
haploid.

Answer 25

diploid.

Question 26

When Mendel crossed purple-flowered pea plants with white-flowered pea plants, he never got offspring with flowers that had an intermediate color. This was counter to the theory of

blending inheritance.
independent assortment.
continuous variation of traits.
direct transmission of traits.

Answer 26

blending inheritance.

Question 27

In humans, the sickle-cell trait is caused by a single mutant allele, but sickle-cell disease only occurs in individuals that are homozygous for the sickle-cell allele. A male and female each carry the trait, but do not have sickle-cell disease. What is the probability that their first two children will both have sickle-cell disease?

1/16
1/8
1/4
1/2

Answer 27

1/16

Question 28

Sometimes, when Mendel crossed two pea plants with each other, he obtained a phenotypic ratio of 3:1 purple-flowered pea plants to white-flowered pea plants. These results are consistent with which set of parents?

Heterozygous purple pea plant and homozygous white pea plant.
Homozygous purple pea plant and homozygous white pea plant.
Heterozygous purple pea plant and homozygous purple pea plant.
Heterozygous purple pea plant and heterozygous purple pea plant.

Answer 28

Heterozygous purple pea plant and heterozygous purple pea plant.

Question 29

The independent assortment of allele pairs is due to __________________________.

the independent segregation of sister chromatid pairs during anaphase I.
the independent segregation of homologous chromosome pairs during anaphase I.
the independent segregation of homologous chromosome pairs during anaphase II.
the independent segregation of non-sister chromatid pairs during anaphase II.

Answer 29

the independent segregation of homologous chromosome pairs during anaphase I.

Question 30

An extensive study was conducted on identical twins who were separated at birth. Among other things, the study showed that the individual from each pair who received better nutrition during childhood tended to score higher on standardized intelligence tests. This can best be described as an example of how _____________________.

mutation alters phenotype.
mutation alters genotype.
environment alters genotype.
environment alters phenotype.

Answer 30

environment alters phenotype.

Question 31

If a single gene has 3 or more alternative forms, this is called _________________.

epistasis.
multiple alleles.
blending inheritance.
pleiotropy.

Answer 31

multiple alleles.

Question 32

During his experiments with pea plants, Mendel referred to the trait that was expressed in the F1 or first filial generation as _________________.

independent.
homozygous.
heterozygous.
dominant.

Answer 32

dominant.

Question 33

Let P = purple flowers and p = white, and T = tall plants and t = short. If the uppercase letters represent the dominant alleles, what is the phenotype of a plant with the genotype PpTt?
white flowers, tall
white flowers, short
purple flowers, short
purple flowers, tall

Answer 33

purple flowers, tall

Question 34

An allele for a particular trait that is only expressed in the presence of a second copy of the same allele is called ________________.

dominant.
codominant.
recessive.
incompletely dominant.

Answer 34

recessive.

Question 35

Mendel’s Principle of Independent Assortment states that different pairs of ________________.

alleles segregate independently of each other.
sister chromatids segregate independently of each other.
non-sister chromatids segregate independently of each other.
gametes segregate independently of each other.

Answer 35

alleles segregate independently of each other.

Question 36

The observable outward manifestation of the genes of an individual is referred to as its _________________.

genotype.
phenotype.
genetic map.
blueprint.

Answer 36

phenotype.

Question 37

Gene _________refers to the combined processes of transcription and translation.

expression
modification
replication
regulation

Answer 37

Expression

Question 38

A codon is composed of how many bases?

3
1
2
4

Answer 38

3

Question 39

The enzyme beta-galactosidase acts on lactose to form galactose. In turn, the presence of galactose leads to expression of the enzymes responsible for the metabolism of galactose. In this case, lactose is serving as a carbon source and as a(n)

operon.
DNA-binding protein.
inducer.
repressor.

Answer 39

Inducer

Question 40

Eukaryotic and prokaryotic organisms differ in how they process genetic information. Which statements best explain one of these differences?

In prokaryotes, introns are removed before genes are transcribed into mRNA. In eukaryotes, introns are removed after genes are transcribed into mRNA.
In prokaryotes, translation of the mRNA begins before transcription is complete. In eukaryotes, transcription and modification of the mRNA is completed before translation begins.
In prokaryotes, genes are transcribed directly into polypeptides. In eukaryotes, genes are transcribed into RNA which is used to assemble polypeptides.
In prokaryotes, translation occurs before genes are transcribed into mRNA. In eukaryotes, genes are transcribed into mRNA which is then translated into polypeptides.

Answer 40

In prokaryotes, translation of the mRNA begins before transcription is complete. In eukaryotes, transcription and modification of the mRNA is completed before translation begins.

Question 41

A protein that regulates transcription by binding to the operator is known as the

operon.
promoter.
operator.
repressor.

Answer 41

repressor.

Question 42

If you were able to look very closely at a portion of DNA and find methylated histones, you would

be mistaken since only DNA can be methylated, not histones.
be looking at a region of inactive chromatin.
be looking at a region of active chromatin.
be looking at a chromatin remodeling complex.

Answer 42

be looking at a region of inactive chromatin.

Question 43

Gene expression involves two phases, _________ and translation.

condensation
transcription
replication
initiation

Answer 43

transcription

Question 44

The polypeptide-making organelles, which consist of protein combined with RNA, are called

centrosomes.
Golgi bodies.
ribosomes.
centrosomes.

Answer 44

ribosomes.

Question 45

In eukaryotes, translation takes place

on the plasma membrane.
on the nuclear membrane.
inside the nucleus.
on ribosomes.

Answer 45

on ribosomes.

Question 46

The sequence of nucleotides in a DNA molecule is called the _________code.

protein
translation
amino acid
genetic

Answer 46

genetic

Question 47

The DNA-binding proteins of almost all regulatory proteins use one of a small set of shapes that enable them to fit into the DNA major groove. These shapes are called

DNA prints.
structural motifs.
fingerprints.
repressors.

Answer 47

structural motifs.

Question 48

What is the difference between a gene that is derepressed and one that is induced?

A derepressed gene is turned off and an induced gene is activated to be expressed.
There is no difference between a gene that is derepressed and one that is induced.
Genes that are derepressed are turned on because an inducer molecule is present. By comparison, a gene that is induced is turned on because a repressor protein is bound to the operator.
A gene that is derepressed is turned on because a repressor protein is not bound without its cofactor. By comparison, a gene that is induced is turned on because an inducer molecule prevents binding of the repressor.

Answer 48

Genes that are derepressed are turned on because an inducer molecule is present. By comparison, a gene that is induced is turned on because a repressor protein is bound to the operator.

Question 49

During protein synthesis in eukaryotes, what happens during RNA splicing?

The product of transcription, called the primary transcript, is cut and some pieces are joined back together to form the mature mRNA.
The product of transcription, called the primary transcript, is cut and some pieces are joined back together to form the mature tRNA.
The product of translation, called the primary transcript, is cut and some pieces are joined back together to form the mature mRNA.
The product of transcription, called the primary transcript, is cut and all pieces are joined back together to form the mature mRNA.

Answer 49

The product of transcription called the primary transcript, is cut and some pieces are joined back together to form the mature mRNA.

Question 50

Certain proteins can bind to specific DNA regulatory sequences by entering

the major groove of the DNA and reading the nucleotide base pairs.
the minor groove of the DNA and reading the nucleotide base pairs.
the major groove of RNA and reading the nucleotide base pairs.
DNA’s major groove by using DNA polymerase and reading the nucleotide base pairs.

Answer 50

the major groove of the DNA and reading the nucleotide base pairs.

Question 51

Through control of gene expression, a bacterial cell responds to changing _________conditions.

environmental
genetic
protein
internal

Answer 51

environmental

Question 52

The Central Dogma of biology can be stated as

RNA→ DNA→ Proteins.
Proteins→ RNA→ DNA.
DNA→ Proteins→ RNA.
DNA→ RNA→ Proteins.

Answer 52

DNA→ RNA→ Proteins.

Question 53

When a polypeptide is being assembled, the bond that forms between a newly added amino acid and the previous amino acid in the chain is a _________bond.

peptide
hydrophobic
phosphodiester
hydrogen

Answer 53

peptide

Question 54

Regulatory proteins can identify specific sequences on the DNA double helix without unwinding the helix. This is accomplished by inserting

DNA-binding motifs into the minor groove of the double helix where the edges of the nitrogen bases protrude.
RNA polymerase into the major groove of the double helix where the edges of the nitrogen bases protrude.
DNA-binding motifs into the major groove of the double helix where the edges of the nitrogen bases protrude.
DNA polymerase into the major groove of the double helix where the edges of the nitrogen bases protrude.

Answer 54

DNA-binding motifs into the major groove of the double helix where the edges of the nitrogen bases protrude.

Question 55

Vertebrate cells possess a protein that binds to clusters of 5-methylcytosine and ensures the gene will stay in the “off” position. This control of gene regulation is a result of

enhancer expression.
operator suppression.
promoter expression.
methylation.

Answer 55

methylation.

Question 56

Why are there fewer tRNA anticodons than the 61 needed to match each mRNA codon that codes for an amino acid?

There is some flexibility in pairing between the 5’ base of the codon and the 3’ base of the anticodon.
There is some flexibility in pairing between the middle base of the codon and the middle base of the anticodon.
There is some flexibility in pairing between all 3 bases of the codon and all 3 bases of the anticodon.
There is some flexibility in pairing between the 3’ base of the codon and the 5’ base of the anticodon.

Answer 56

There is some flexibility in pairing between the 3’ base of the codon and the 5’ base of the anticodon.

Question 57

A bacterial cell has a nonsense mutation that prevents it from producing a functional sigma subunit for RNA polymerase. Inability to synthesize a functional sigma subunit would have the most direct effect on

translation termination.
transcription elongation.
transcription initiation.
translation initiation.

Answer 57

transcription initiation.

Question 58

A diploid organism that has two identical alleles for a given trait is called _________for that trait.
dominant
codominant
heterozygous
homozygous

Answer 58

homozygous

Question 59

If an individual allele has more than one effect on the phenotype, this is called

pleiotropy.
epistasis.
blending inheritance.
multiple alleles.

Answer 59

pleiotrophy

Question 60

Alternate forms of the same gene are called _______________.
genotypes.
cofactors.
homologues.
alleles.

Answer 60

alleles

Question 61

In modern terminology, Mendel’s heredity “factors” are called ______________.

chromosomes.
DNA.
RNA.
genes.

Answer 61

genes

Question 62

In Mendel’s experiments on seed color in pea plants, when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant, what was the approximate phenotypic ratio among the F2 generation?
9:3:3:1
1 yellow: 3 green
3 yellow: 1 green
1 yellow: 1 green

Answer 62

3 yellow: 1 green

Question 63

Let P = purple flowers and p = white, and T = tall plants and t = short. What are the genotypes of the gametes that are produced by a plant that is heterozygous for both traits?

P, p, T, and t
PT and pt
PT, Pt, pT, and pt
PpTt only

Answer 63

PT, Pt, pT, and pt

Question 64

DNA replication always proceeds by adding new bases to the _________ end of an existing strand.

5’
3’
2’
4’

Answer 64

3’

Question 65

Watson and Crick developed a model of DNA in which the two strands twist into the shape of a _________.

double pleated sheet
circle
double helix
helix

Answer 65

double helix

Question 66

Because the two strands of a DNA molecule are _________ to each other, either one can be used as a template to reconstruct the other.

identical
bound
antiparallel
complementary

Answer 66

complementary

Question 67

In synaptic signaling, neurotransmitters are released into a space that is referred to as a:__________________.

paracrine space.
neuron junction.
gap junction.
chemical synapse.

Answer 67

chemical synapse

Question 68

If a mutation prevented synthesis of the beta subunit of DNA pol III, which would be most affected?

Formation of RNA primers
Removal of RNA primers
Processivity
DNA unwinding

Answer 68

processivity

Question 69

Avery and his coworkers showed that the agent responsible for changing nonvirulent bacteria into virulent bacteria was __________________.

DNA.
polysaccharide.
lipid.
RNA.

Answer 69

DNA

Question 70

Endonucleases and exonucleases are enzymes that can remove nucleotides from a polynucleotide chain. An endonuclease removes nucleotides _______ while an exonuclease removes nucleotides _________.

internally; from the ends of the chain.
from the ends of the chain; internally
from the 3’ end of the chain; from the 5’ end of the chain
from the 5’ end of the chain; from the 3’ end of the chain

Answer 70

internally; from the ends of the chain.

Question 71

In Griffith’s experiments, ______________________.
mice infected with heat-killed virulent bacteria and heat-killed nonvirulent bacteria developed pneumonia and died.

mice infected with live nonvirulent bacteria developed pneumonia and died.

nonvirulent bacteria transformed the virulent bacteria into a nonvirulent variety.

mice infected with heat-killed virulent bacteria and live nonvirulent bacteria developed pneumonia and died.

Answer 71

mice infected with heat-killed virulent bacteria and live nonvirulent bacteria developed pneumonia and died.

Question 72

What is required for formation of the transcription initiation complex in eukaryotes?

Binding of a transcription factor to the TATA box, followed by recruitment of additional transcription factors and recruitment of RNA polymerase II

Binding of a transcription factor to the transcription bubble, followed by recruitment of additional transcription factors and recruitment of RNA polymerase III

Binding of the sigma subunit to the start site followed by recruitment of RNA polymerase II

Binding of RNA polymerase II to the TATA box, followed by recruitment of transcription factors

Answer 72

Binding of a transcription factor to the TATA box, followed by recruitment of additional transcription factors and recruitment of RNA polymerase II

Question 73

Which base in an anticodon will pair with the base adenine in a codon?

Guanine
Uracil
Cytosine
Thymine

Answer 73

uracil

Question 74

DNA affects the traits of an organism by providing the instructions for synthesizing _________.

proteins
codons
amino acids
nucleotides

Answer 74

protiens

Question 75

You are working to identify enhancer regions of a particular gene. The best place to look is

immediately upstream of the promoter.
immediately downstream of the promoter.
primarily upstream of the promoter, possibly some distance away.
primarily downstream of the promoter, including the exons of the coding region.

Question 76

Which molecule combines with proteins to form both the large and small ribosomal subunits?
rRNA
RNA polymerase
tRNA
DNA

Answer 76

rRNA

Question 77

Messenger RNA molecules contain information that is used to synthesize _________.

fatty acids
amino acids
polypeptides
nucleotides

Answer 77

polypeptides

Question 78

The gene encoding apolipoprotein B exists in two isoforms, APOB100 and APOB48. These two forms are produced as a result of

tissue-specific expression.
a gene mutation that results in a stop codon.
alternative splicing.
RNA editing.

Answer 78

RNA editing

Question 79

If the sequence of bases in the template strand of a DNA molecule is 3’ ATCGCTCC 5’, what is the sequence of bases in the RNA that is transcribed from this molecule?

5’ TAGCGAGG 3’
3’ TAGCGAGG 5’
5’ UAGCGAGG 3’
3’ UAGCGAGG 5’

Answer 79

5’ UAGCGAGG 3’

Question 80

Most eukaryotic genes contain noncoding sequences called _________that are interspersed with the coding sequences.
exons
spliceosomes
codons
introns

Answer 80

introns

Question 81

Cells conserve energy and resources by making active proteins only when they are needed. If a protein is not needed, which of the following methods of control would be the most energy-efficient?

Block transcription
Prevent translation of the mRNA
Degrade the protein after it is made
Degrade the mRNA after it is made

Answer 81

Block transcription

Question 82

In prokaryotes, the form of RNA polymerase that can accurately initiate synthesis of RNA is called
the sigma subunit.
the holoenzyme.
the core polymerase.
RNA polymerase II.

Answer 82

the holoenzyme.

Question 83

Transcription in prokaryotes is carried out by _________, which unwind(s) and transcribe(s) the gene.
RNA polymerase
helicase
RNA polymerase III
transcription factors

Answer 83

RNA polymerase

Question 84

When E. coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the
trp regulator.
trp operon.
trp suppressor.
trp promoter.

Answer 84

trp operon.

Question 85

A scientist makes three artificial mRNA strands:

(x) 5’ AAAUUUAAAUUUAAAUUUAAAUUUAAA 3’

(y) 5’ UUUCCCUUUCCCUUUCCCUUUCCCUUU 3’

(z) 5’ AUAUAUAUAUAUAUAUAUAUAUAUAU 3’

When she analyzes the polypeptides produced, she finds that:
x produces a polypeptide that is 50% phenylalanine and 50%lysine.
y produces a polypeptide that is 50% phenylalanine and 50% proline.
z produces a polypeptide that is 50% isoleucine and 50% tyrosine.

Based on these results only, the best conclusion to make is that

AUA codes for isoleucine
AAA codes for lysine and AUA codes for isoleucine
AAA codes for lysine
AAA codes for phenylalanine

Answer 85

AAA codes for lysine

Question 86

Codons that serve as “stop” signals for translation are recognized by

translation terminators.
aminoacyl-tRNA synthetases
tRNA.
release factors.

Answer 86

release factors

Question 87

The connection that exists between genes and hereditary traits is based on using the information encoded in genes to synthesize

nucleotides.
codons.
complementary bases.
proteins.

Answer 87

proteins

Question 88

If you were given a bacterial strain with a mutation in the promoter region of the trp operon the most likely effect would be

lack of expression of just the first gene in the operon.
enabling the trp operon to be expressed in the absence of tryptophan.
depression of the trp operon.
interference with RNA polymerase binding.

Answer 88

interference with RNA polymerase binding.

Question 89

In eukaryotes, each type of RNA polymerase recognizes a different

transcription factor.
promoter.
start codon.
stop codon.

Answer 89

promoter

Question 90

Initiation of transcription differs from initiation of DNA replication in several ways. One difference is that initiation of transcription does not require

a promoter.
enzymes.
a primer.
a DNA template strand.

Answer 90

a primer

Question 91

The polypeptide-making organelles, which consist of protein combined with RNA, are called

centrosomes.
centrosomes.
ribosomes.
Golgi bodies.

Answer 91

ribosomes

Question 92

If a strain of bacteria had a mutation that blocked expression of the lac repressor, what would you expect as a result?

The mutant strain would grow at the same rate as wildtype if lactose was not present.
The mutant strain would outcompete wildtype strains, since it could always utilize lactose.
The mutant strain would act the same, because it would still require lac activator protein to turn on.
The mutant strain would waste energy producing enzymes in the absence of lactose.

Answer 92

The mutant strain would waste energy producing enzymes in the absence of lactose.

Question 93

To remove noncoding sequences in the pre-mRNA of eukaryotes, multiple snRNPs combine with proteins to form a larger complex called the _________.

ribosome
3’ poly-A tail
spliceosome
5’ cap

Answer 93

spliceosome

Question 94

The mutation responsible for Huntington’s disease is a

missense mutation.
triplet repeat expansion mutation.
frameshift mutation.
nonsense mutation.

Answer 94

triplet repeat expansion mutation.

Question 95

In prokaryotes, the form of RNA polymerase that can accurately initiate synthesis of RNA is called

RNA polymerase II.
the core polymerase.
the holoenzyme.
the sigma subunit.

Answer 95

the holoenzyme.

Question 96

Codons that serve as “stop” signals for translation are recognized by

tRNA.
release factors.
aminoacyl-tRNA synthetases
translation terminators.

Answer 96

release factors

Question 97

During protein synthesis in eukaryotes, which molecule passes from the nucleus to the cytoplasm and specifies the sequence of amino acids in the new polypeptide?

tRNA
rRNA
DNA
mRNA

Answer 97

mRNA

Question 98

The A, P, and E sites are progressively occupied by amino acids being assembled into a polypeptide. These sites are part of

tRNA.
the large ribosomal subunit.
DNA.
mRNA.

Answer 98

the large ribosomal subunit.

Question 99

When E. coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the

trp suppressor.
trp regulator.
trp operon.
trp promoter.

Answer 99

trp operon

Question 100

The hallmark of multicellular organisms is their ability to

adjust quickly to outside environment.
maintain homeostasis.
grow and divide rapidly.
respond by gene action to oxygen availability.

Answer 100

maintain homeostasis.

Question 101

A protein that regulates transcription by binding to the operator is known as the

operon.
repressor.
promoter.
operator.

Answer 101

repressor

Question 102

In eukaryotes, each type of RNA polymerase recognizes a different

start codon.
transcription factor.
stop codon.
promoter.

Answer 102

promoter

Question 103

You are studying regulation of a prokaryotic operon. Experiments show that expression of the operon is increased when levels of biosynthetic product from that pathway are low. Based on this information, what is a likely mode of regulation?

The product binds to the biosynthetic enzymes, blocking them directly.
The product binds an activator, helping RNA polymerase to bind the promoter.
The product binds a repressor, preventing it from binding the operator.
The product binds a repressor, allowing it to bind the operator.

Answer 103

The product binds a repressor, allowing it to bind the operator.

Question 104

Living systems are able to conserve and transfer information from one generation to the next due to the presence of __________________.

Homeodomain protein
Deoxyribonucleic acid
Ordered complexity
Cell membrane

Answer 104

Deoxyribonucleic acid

Question 105

A group of humming birds of the same species living in the same area is an example of a/an ________________.

Ecosystem
Community
Population
Biosphere

Answer 105

Population

Question 106

The characteristics of life include all the following EXCEPT __________________

Sensitivity
Homeostasis
Movement
Growth

Answer 106

Movement

Question 107

The amazon rainforest which is seen as an important carbon sink is made up of numerous animal and plant species with abundant water sources. Where in the biological hierarchy will all these correctly fit into?

Population
Ecosystem
Biosphere
Community

Answer 107

Ecosystem

Question 108

Scientist Tonya Bates is setting up an experiment to measure the effect of a new fertilizer, Bron24, on cashew production in different species of the crop. Control variables will include _____________.

Rate of transpiration
Rate of respiration
Quantity of fertilizer
Species of cashew

Answer 108

Quantity of fertilizer