Genetics MCQs
Genetics MCQs
Answer these 400+ Genetics MCQs and assess your grip on the subject of Genetics. Scroll below and get started!
1: ____ is an accessory protein that acts to chaperone nucleosome assembly.
A. Histone 3.3
B. Nucleoplasmin/N1
C. Histone H1
D. CAF1/Asf1
2: ________ is to transcription as ________ are to translation.
A. Alternative splicing ; pre-mRNA
B. RNA polymerase; ribosomes
C. Ribosomes ; RNA polymerase
D. Pre-mRNA ;RNA polymerase
3: A 1:1:1:1 ratio of offspring from a dihybrid testcross indicates that ___________.
A. The genes are not linked or are more than 50 map units apart.
B. Have the same order of genes but different intergenic distances.
C. Recessive, and that these genes are located 4 map units apart.
D. None of these
4: A change from uug to uag would thus be a(n) _______ mutation.
A. Silent; missense
B. Nonsense; silent
C. Frame-shift; missense
D. Silent; nonsense
E. Nonsense; frame-shift
5: A cross that involves two traits is called a ______ cross.
A. Monohybrid
B. Dihybrid
C. Punnett
D. Test
E. Homozygous
6: A ddntp, used often in dna sequencing, lacks a(n) ________ at the ________ and ________ carbons.
A. True
B. OH; 2'; 3'
C. DNA sequencing
D. Filter-bound DNA
7: A dominant allele is best defined as ________.
A. An allele that stops or hides the expression of the other allele
B. The person has two identical alleles for the gene responsible for the trait
C. Carriers are not eliminated by the disease before passing the defective alleles on to their offspring
D. Incomplete dominance
E. Phenotype
8: A gene is usually _____.
A. The same thing as a chromosome
B. The information for making a polypeptide
C. Made of RNA
D. Made by a ribosome
9: A gene made of __________ is transcribed into __________ and then translated to form a __________.
A. DNA ... RNA ... protein
B. U ... A....D
C. DNA → RNA → protein
D. Substitution of one nucleotide
10: A genetic locus has two alleles. one has a frequency of 0.12; the other has a frequency of _______.
A. 0.81
B. 0.88
C. 0.89
D. 0.87
11: A human female has _____ chromosomes in each skin cell and _____ chromosomes in each egg.
A. 46; 23
B. 23; 46
C. 46; 46
D. 23; 23
12: A monohybrid cross is made between plants that _____.
A. Have experienced only one hybrid generation
B. Differ in only one trait
C. Are identical
D. Are self-pollinated
13: A phenotypic ratio of 9:3:3:1 in the offspring of a cross indicates that _____.
A. Both parents are heterozygous for both genes
B. Calculate the probability of a child having either sickle-cell anemia or cystic fibrosis if parents are each heterozygous for both.
C. In rabbits and many other mammals, one genotype (ee) prevents any fur color from developing.
D. Skin pigmentation in humans
14: A plant with the genotype aabbcc is __________.
A. Homozygous recessive individual
B. Homozygous for two different genes
C. The gene for hemophilia is sex-linked
D. All of the dominant phenotype
15: A plasmid differs from the bacterial chromosome in that it is __________.
A. Plasmids contain genes that are NOT essential for cellular growth and replication.
B. Catalyze the formation of phosphodiester bonds between ribonucleotides.
C. Additional genetic traits that are needed only under certain circumstances
D. Allows coordinated expression of multiple related genes in prokaryotes.
16: A ribozyme is __________.
A. An RNA molecule that functions as an enzyme
B. The location in a cell where ribosomal RNAs (rRNAs) are made
C. An example of rearrangement of exons caused by alternative RNA splicing
D. An exception to the one gene-one enzyme hypothesis
E. A cutting enzyme involved in DNA damage repair
17: A robertsonian translocation is considered non-reciprocal because _______.
A. A copy of the insertion sequence becomes integrated at a new location
B. Two haploid gametes fuse to form a diploid cell
C. The smaller of the two reciprocal products of translocated chromosomes is lost
D. They may be sterile and unable to produce offspring.
18: A stretch of 150 nucleotides in a coding region would code for _______ codons.
A. 30
B. 50
C. 150
D. 450
E. 750
19: Aabb × aabb is an example of ____.
A. Fertilization
B. DNA polymerase
C. Incomplete dominance
D. MRNA, tRNA, rRNA
E. A dihybrid cross
20: According to chargaff's rules, ___ always pairs with ____, and _____ always pairs with _____.
A. A; G; T; C
B. A; T; G; C
C. A; C; G; T
D. C; T; G; A
E. G; U; A; C
21: "all of the following are dna sequencing techniques except _____. select all that apply.
A. DNA fingerprinting
B. Maxam and Gilbert method
C. Chain termination method
D. Mullis chain-terminating sequencing
22: All of the following are required in complementation testing in yeast except _______.
A. Mutations that are recessive
B. Diploid cells
C. Two or more mutations that affect a single phenotype
D. An auxotrophic organism
23: All of the following are related to telomeres except __________.
A. Telomerase enzyme
B. Links to the aging process
C. Being found in eukaryotes and prokaryotes
D. Short tandem repeats located at the ends of telomeres
24: All of the following conditions are required for hardy-weinberg equilibrium except __________.
A. Duplication
B. Natural selection
C. Balancing selection
D. Mutation
E. Human fingerprints
25: An mrna molecule has 540 codons. it must have at least _______ nucleotides.
A. 180
B. 270
C. 540
D. 1,080
E. 1,620
26: Bacterial dna polymerase i does not have ________ activity?
A. 3' to 5' exonuclease activity
B. 5' to 3' exonuclease activity
C. Endonuclease activity
D. 5' to 3' DNA synthesis activity
27: Bergman’s rule suggests that there is a correlation between temperature and ________________.
A. Size
B. Pressure
C. Space
D. Mass
28: Brca1 and brca2 are considered to be tumor-suppressor genes because _____.
A. Turned off whenever tryptophan is added to the growth medium.
B. Starts when the pathway's substrate is present.
C. Their normal products participate in repair of DNA damage.
D. The occurrence of mRNAs for the production of tissue-specific proteins
29: Codons are base pair sequences that ________.
A. Prevent mRNA synthesis
B. Code for amino acids
C. Alterations in the DNA base sequence
D. Deoxyadenosine
30: Crossing over ________ genes into assortments of ________ not found in the parents.
A. Recombines linked; alleles
B. Combines unlinked; alleles
C. Combines linked; genes
D. Recombines unlinked; genes
31: Crossing over ____________ the number of recombinant offspring.
A. Decreases
B. Not assort independently.
C. Increases
D. Coupling
32: Disruptive selection favors individuals at ______ of variation
A. One extreme
B. Both extremes
C. In the middle
D. None of the above
33: During replication dna _____
A. Remains intact
B. Makes rna
C. Is copied
D. Directs protein synthesis
34: During telophase ______.
A. Carry genes controlling the same inherited characteristics
B. Homologous chromosomes line up in the middle of the cell
C. The events of prophase are reversed
D. Chromosomes line up in the middle of the cell
35: During the transcription of a given portion of a dna molecule _____.
A. Manufactured proteins to be short and defective
B. During transcription
C. A silent or neutral mutation
D. Cleavage of a polypeptide into two or more chains
E. MRNA is synthesized on only one of the chains
36: During translation, _____ is synthesized in the _____.
A. DnaA, opens the complex
B. Exons, introns
C. Nucleus, introns
D. Polypeptides, mRNA sequences and cellular machinery
37: Each round of pcr ______.
A. Increases the amount of DNA by 2n, where n = primer length
B. Doubles the amount of DNA
C. Increases the amount of DNA by 2n, where n = reaction temperature
D. Cuts a new set of DNA fragments
38: Environmental factors typically influence inheritance of ________.
A. Multiple alleles
B. Codominance
C. Trihybrid crosses
D. Polygenic traits
39: Eric has blue eyes. since the gene for blue eyes is recessive, eric must be ______ for that trait.
A. Dizygotic
B. Embryonic
C. Monozygotic
D. Homozygous
40: Gene flow is accomplished by ______.
A. Genetic drift
B. Sexual recombination
C. Mutation
D. Migration
E. Natural selection
41: Genes provide the information needed to produce _____ in the cell.
A. Enzymes
B. Lipids
C. Ribosomes
D. Glucose
42: Genetic drift is _____.
A. An important microevolutionary mechanism in large populations
B. The mechanism by which new alleles originate
C. More likely to have an impact on small populations
D. Adaptive
43: Genetic drift is the result of ______.
A. Chance
B. Environmental variation
C. Natural selection
D. A large gene pool
E. Differential reproductive success.
44: Genetic drift produces variation for evolution when ________.
A. A gene pool decreases because a smaller group establishes a new population
B. Chance events cause allele frequencies to fluctuate unpredictably
C. Sudden change in environment drastically reduces the gene pool
D. A population has heritable traits better suited to the environment
45: Genetic variation _____
A. Is created by the direct action of natural selection
B. Must be present in a population before natural selection can act upon the population
C. Tends to be reduced by when diploid organisms produce gametes
D. Arises in response to changes in the environment
46: Genetic variation in bacterial populations cannot result from __________.
A. Transformation
B. Transduction
C. Meiosis
D. Conjugation
E. Mutation
47: Hiv and phage lambda both __________.
A. Surrounds the nucleic acid of a virus
B. Integrate their DNA into the host's chromosome
C. Considered to be alive
D. Moves from the nucleus to the cytoplasm following RNA processing
48: If a disease is caused by a dominant allele, it means that a person with the disease ________.
A. In the sequence of bases
B. Polygenic inheritance.
C. Huntington disease
D. Could be either homozygous or heterozygous for the allele
E. Hydrogen bonds between bases
49: If an allele is dominant in one sex and recessive in another, it is an example of ___________.
A. Incomplete dominance
B. Codominance
C. Simple Mendelian inheritance
D. Sex-limited inheritance
E. Sex-influenced inheritance
50: If the dna in a cell consists of 20% adenine, then it will also contain ___ guanine.
A. 40%
B. 50%
C. 30%
D. 20%
51: If there is 24% guanine in a dna molecule, then there is ________ cytosine.
A. 52%
B. 24%
C. 48%
D. Impossible to determine
52: In eukaryotes, general transcription factors ________ .
A. Inactivation of the selected genes
B. Decreased chromatin condensation
C. Sets of regulatory proteins
D. Bind to other proteins or to the TATA box
E. Alternative forms of RNA splicing
53: In eukaryotes, when mature mrna is hybridized to complementary dna, ______.
A. Exons loop out as single-stranded regions of DNA
B. Introns loop out as single-stranded regions of DNA
C. Introns loop out as single-stranded regions of RNA
D. Exons loop out as single-stranded regions of RNA
54: In eukaryotic cells the first step in protein synthesis is the _____.
A. Removal of introns from RNA and the stitching together of exons
B. Transferring of information from DNA to messenger RNA
C. Translation of an RNA nucleotide sequence into a sequence of amino acids
D. Translation of a DNA nucleotide sequence into a sequence of amino acids
E. Linking of nucleotides to form a polypeptide
55: In gene-cloning projects, plasmids function to ______.
A. Recognized by restriction enzymes
B. Allow replication of the DNA thats being cloned
C. Plasmid and bacterial cell replication
D. Probe the library using a labeled single-stranded DNA complementary to the gene
56: In pcr, _______ creates single-stranded dna template molecules.
A. Heat
B. High salt concentration
C. DNA polymerase
D. Exonuclease
E. A primer
57: In prokaryotes, operons _____.
A. Regulate the catalytic activities of specific proteins
B. Regulate the rate of transcription of a set of genes
C. Phosphorylate specific polypeptide chains
D. Transcribe structural genes
58: In the _______ of lactose, the lac ______ binds to the lac _______ site.
A. Ribosomes
B. Transcription factor binding
C. Absence; repressor; operator
D. Provides a site for the repressor to bind
59: In the control of gene expression in bacteria, a regulatory gene __________.
A. Is transcribed continuously
B. Is not contained in the operon it controls
C. Has its own promoter
D. Codes for repressor proteins.
E. All of the listed responses are correct.
60: In the hardy-weinberg equation, p and q are _____.
A. Mutation rates
B. Phenotypes
C. Genotypes
D. Measures of fitness
E. Allele frequencies
61: In the lactose operon of e. coli, the crp-camp complex is a(n) _____ of transcription.
A. Positive regulator
B. Enhancer
C. Silencer
D. Negative regulator
62: In the united states, about _____ of the population is overweight; more than _____ are obese.
A. One-thirds; half
B. Two-thirds; half
C. One-thirds; a quarter
D. Two-thirds; a quarter
63: In transcription, ________.
A. The mRNA produced is complementary to one strand of the DNA
B. Both strands of the DNA are copied
C. Uracil pairs with thymine
D. A double helix containing one parent strand and one daughter strand is produced
E. The mRNA produced is identical to the parent DNA
64: Inbreeding can lead to a decrease in genetic diversity and _____.
A. Hybrid infertility
B. Allele frequency
C. All of these
D. Inbreedng depression
65: Introns are ______.
A. DNA sequences to which silencers bind
B. DNA sequences to which activators bind
C. Noncoding DNA sequences
D. Expressed DNA sequences
E. The product of RNA splicing
66: Microinsertions and microdeletions often result in ________ mutations.
A. Silent
B. Frameshift
C. Auxotrophic
D. Advantageous
67: Morgan's analysis of a white-eyed male drosophila mutation helped explain ________.
A. Autosomal dominance
B. Independent assortment
C. X-linked inheritance
D. Crossing over
E. Random mutation
68: Most human variation is due to _____ traits.
A. Trait L
B. Complex
C. Normal
D. None of these
69: Most of the known single-gene disorders are _____.
A. Severe dominant disorder
B. Dominant
C. Seriously disabling
D. None of these
70: Most recessive genetic disorders are _____.
A. On the autosomes
B. X-linked
C. Additive
D. Polygenic
71: On any given_____, there are a number of genes, but not all the genes will be coding for proteins.
A. Tumor
B. Chromosome
C. Helix
D. Nucleotide
72: Prototrophs are bacteria that can grow on ________ medium.
A. Auxotrophs
B. Prototrophs
C. Minimal
D. F+ cells
73: Replication of dna begins at a/n ___ rich area.
A. Uracil-adenine
B. Guanine-cytosine
C. Adenine-cytosine
D. Guanine-adenine
E. Adenine-thymine
74: Scientists have found that _____.
A. Genetic diversity decreased as early humans migrated away from Africa and founded new populations
B. Sperm do not contribute their mitochondria to the zygote.
C. All humans alive today are related to a single female ancestor
D. The ability to walk upright preceded the evolution of a larger brain
75: Separation of sister chromatids occurs _______.
A. At anaphase in mitosis and anaphase II in meiosis
B. Rough endoplasmic reticulum and ribosomes
C. Metaphase chromosomes
D. Anaphase II
E. Reciprocal exchange of DNA between homologs during prophase I
76: Shown below is a ribosome in the process of translation. the p site of a ribosome _____.
A. Deliver amino acids to their proper site during protein synthesis
B. Holds the growing polypeptide chain
C. Manufactured proteins to be short and defective
D. The information for making a polypeptide
77: Starting around age ___, organ size and efficiency begin to decrease.
A. 30
B. 40
C. 50
D. 70
78: Stem canker, cyst nematodes and late foliar disease are major diseases of__________ in brazil.
A. Soybeans
B. Maize
C. Green beans
D. Safrinha
79: Sympatric speciation is _____. see concept 24.2 (page 511)
A. Reduced hybrid viability
B. The appearance of a new species in the same area as the parent population
C. Punctuated equilibrium
D. Sympatric speciation and polyploidy
80: Telomerase reads ________ as a template and synthesizes ________ as a product.
A. RNA; DNA
B. DNA; DNA
C. RNA; RNA
D. DNA; RNA
81: The collection of _____ in a population constitutes that population's gene pool.
A. Hybrid infertility
B. Allele frequency
C. Alleles
D. None of these
82: The discontinuous aspect of replication of dna in vivo is caused by ________.
A. Polymerase slippage
B. Trinucleotide repeats
C. The 5' to 3' polarity restriction
D. Topoisomerases cutting the DNA in a random fashion
E. Sister-chromatid exchanges
83: The disproportionately high appearance of polydactylism among the amish suggests that _______.
A. It is a common mutation
B. It is a common birth defect in Pennsylvania
C. It was overrepresented in the gene pool of the original Amish settlers
D. Humans are prone to this birth defect
84: The process of ________ is described as semiconservative.
A. Translation
B. Transcription
C. Mismatch repair
D. Transformation
E. DNA replication
85: The product of the p53 gene _____.
A. Causes cells to reduce expression of genes involved in DNA repair
B. Allows cells to pass on mutations due to DNA damage
C. Slows down the rate of DNA replication by interfering with the binding of DNA
D. Polymerase
E. Inhibits the cell cycle
86: The radioactive isotope 32p labels the t2 phage's _____.
A. DNA
B. RNA
C. Both
D. None of these
87: The relationship between a gene and a messenger rna is that ________.
A. MRNAs are made from genes
B. All genes are made from mRNAs
C. MRNAs make proteins, which then code for genes
D. MRNA is directly responsible for making Okazaki fragments
E. Genes are made from mRNAs
88: The sos dna repair system is __________.
A. It can be copied, transcribed, and translated into a desired protein.
B. A last ditch effort to prevent cell death from large amounts of damage.
C. They cut DNA at sites, called recognition sites, that have specific nucleotide sequences.
D. Stay healthy, because their immune systems can kill this strain easily
89: The strand of dna that is not transcribed is called the ______ strand.
A. Coding
B. Non-coding
C. Replicate
D. Inert
90: The tata box is a __________ that allows for the binding of __________ and __________.
A. Eukaryotic promoter; transcription factors; ribozymes
B. Prokaryotic promoter; translation factors; ribosome
C. Eukaryotic promoter; transcription factors; RNA polymerase II
D. Prokaryotic promoter; transcription factors; RNA polymerase II
E. Eukaryotic promoter; translation factors; ribosome
91: __________ function(s) as the template during translation.
A. Transcription
B. Messanger rna
C. Transfer rna
D. Ribosomal rna
92: A mutation can cause a change __________.
A. In the shape of a protein, in the amino acid sequence of a protein, in the way the cell cycle is regulated that is beneficial to the cell
B. In the shape of a protein, in the amino acid sequence of a protein
C. In the shape of a protein
93: A phenotype can consist of _____ as well as _____ characteristics.
A. 1 in 10
B. First half
C. Evocative genotype-environment
D. Physical; psychological
94: Linked genes are usually ________.
A. Codominant
B. Found on the Y chromosome
C. Located close together on a chromosome
D. Found on the X chromosome
95: Part a in the diagram below, the gray unit represents _____.
A. RNA
B. DNA
C. None of these
96: The size of dna is often given in the number of _____ that it contains.
A. Genes
B. Codons
C. Base pairs
D. Proteins
E. Triplets
97: The actual photographed resolution is known as the ______ resolution.
A. Native
B. Original
C. Optical
D. Raw
98: The genetic code is the link between the __________ and the __________ that they represent.
A. Somatic cells; diploid (2n)
B. MRNA codons; 20 amino acids
C. Nucleotides; nitrogenous base
D. Each daughter DNA consists of one new helix and one old helix
99: The genetic information is coded in dna by the ________.
A. The sequence of the nucleotides
B. The regular alteration of sugar and phosphate molecules.
C. The arrangement of the histones
D. The three-dimensional structure of the double hellix
100: Transcription and translation take place in the ________ and ________, respectively.
A. Nucleus; cytoplasm
B. Nucleolus; nucleus
C. Nucleolus; cytoplasm
D. Cytoplasm; nucleus
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