Human Genetics Practice Ch 10-14 Exam 154 Questions with Verified Answers
The process of copying a gene's DNA sequence into a sequence of RNA is called
... [Show More] _____.
A) replication
B) transcription
C) translation
D) PCR - CORRECT ANSWER B) transcription
RNA contains which nitrogen-containing bases?
A) adenine, thymine, guanine, cytosine, uracil
B) adenine, thymine, guanine, cytosine
C) thymine, guanine, cytosine, uracil
D) adenine, guanine, cytosine, uracil - CORRECT ANSWER D) adenine, guanine, cytosine, uracil
Which of the following statements is true regarding introns?
A) Introns are the parts of mRNA that are translated.
B) Introns have no function.
C) In general, human genes have fewer introns than genes of other organisms.
D) Introns are removed from mRNA molecules. - CORRECT ANSWER D) Introns are removed from mRNA molecules.
Which mode of information transfer usually does not occur?
A) DNA to DNA
B) DNA to RNA
C) DNA to protein
D) All of the above occur in a working cell. - CORRECT ANSWER C) DNA to protein
A geneticist isolates a gene for a specific trait under study. She also isolates the corresponding mRNA. Upon comparison, the mRNA is found to contain 1,000 fewer bases than the DNA sequence. Did the geneticist isolate the wrong DNA?
A) Yes, mRNA is made from a DNA template and should be the same length as the gene sequence.
B) Yes, the mRNA should contain more bases than the DNA sequence because bases flanking the gene are also transcribed.
C) No, the final mRNA contains only exons, the introns have been removed.
D) No, the mRNA was partially degraded after it was transcribed. - CORRECT ANSWER c) No, the final mRNA contains only exons, the introns have been removed.
RNA is synthesized against one strand of the double helix with the assistance of the enzyme _____.
A) ligase
B) DNA polymerase
C) RNA polymerase
D) aminoacyl transferase - CORRECT ANSWER C) RNA polymerase
Which molecule contains codons?
A) DNA
B) mRNA
C) tRNA
D) rRNA - CORRECT ANSWER B) mRNA
Transcription occurs in the ____ direction along the template strand forming an mRNA in the ____ direction.
A) 5' to 3'; 5' to 3'
B) 5' to 3'; 3' to 5'
C) 3' to 5'; 5' to 3'
D) 3' to 5'; 3' to 5' - CORRECT ANSWER B) 5' to 3'; 3' to 5'
____ regulate which genes or subsets of genes are transcribed in a particular cell type.
A) Transcription factors
B) Chaperone proteins
C) RNA polymerases
D) Transcription is not regulated. - CORRECT ANSWER A) Transcription factors
A DNA strand with the sequence 3' AACGTAACG 5' is transcribed. What is the sequence of the mRNA molecule synthesized?
A) 5' AACGTAACG 3'
B) 5' UUGCAUUGC 3'
C) 5' AACGUAACG 3'
D) 5' TTGCATTGC 3' - CORRECT ANSWER B) 5' UUGCAUUGC 3'
What form of RNA binds to both the codon and an amino acid?
A) mRNA
B) tRNA
C) rRNA
D) None of the above. - CORRECT ANSWER B) tRNA
What area of a gene does the RNA polymerase bind to?
A) promoter
B) exon
C) intron
D) codon - CORRECT ANSWER A) promoter
Following transcription, how is the 5' end of mRNA modified in eukaryotic cells?
A) It is not modified.
B) It is removed by alternative splicing.
C) A poly A tail is added.
D) A cap is added. - CORRECT ANSWER D) A cap is added.
RNA is transcribed using the ____ strand of DNA.
A) coding
B) alternate
C) template
D) non-template - CORRECT ANSWER C) template
Which of the statements below is FALSE?
A) The genetic code is overlapping.
B) The genetic code is universal.
C) Degenerate codons specify the same amino acids.
D) The genetic code is triplet in nature. - CORRECT ANSWER A) The genetic code is overlapping.
Transcription and translation of a gene composed of 30 nucleotides could form a protein containing no more than ____ amino acids.
A) 10
B) 15
C) 60
D) 90 - CORRECT ANSWER A) 10
The first mRNA codon to specify an amino acid in a protein sequence is always _____.
A) TAC
B) UAA
C) UAG
D) AUG - CORRECT ANSWER D) AUG
Transfer RNAs bind to messenger RNAs during translation via their _____.
A) codon
B) anticodon
C) template - CORRECT ANSWER B) anticodon
Of the ____ different possible codons, ____ specify amino acids and ____ signal stop.
A) 20; 17; 3
B) 180; 20; 60
C) 64; 61; 3
D) 61; 60; 1 - CORRECT ANSWER C) 64; 61; 3
The effort to decipher the genetic code was led by ____.
A) Nirenberg and Matthaei
B) François Jacob and Jacques Monod
C) Watson and Crick
D) Francis Crick - CORRECT ANSWER A) Nirenberg and Matthaei
An antibiotic interferes with the ability of the ribosome to move. What effect would exposure to this chemical have on a bacterial cell?
A) Protein synthesis will be enhanced.
B) The protein synthesized will be shorter than normal.
C) The protein synthesized will be longer than normal.
D) No proteins will be produced. - CORRECT ANSWER D) No proteins will be produced.
What sequence on the template strand of DNA corresponds to the first amino acid inserted into a protein?
A) TAC
B) UAA
C) UAG
D) AUG - CORRECT ANSWER A) TAC
Which of the following is an example of the degeneracy of the genetic code?
A) A given amino acid has more than one codon.
B) Each codon specifies more than one amino acid.
C) The first base specifies the amino acid.
D) The genetic code is not degenerate. - CORRECT ANSWER A) A given amino acid has more than one codon.
During translation, the _____ site within the ribosome holds the growing amino acid chain while the ____ site holds the next amino acid to be added to the chain.
A) A; P
B) P; A
C) A; B
D) B; A - CORRECT ANSWER B) P; A
Translation terminates when _____.
A) the A site is empty
B) a stop codon is present in the A site
C) a release factor is present in the P site
D) translation reaches the end of the mRNA - CORRECT ANSWER B) a stop codon is present in the A site
In eukaryotic cells, transcription occurs in the _____ and translation occurs in the ______.
A) nucleus; nucleus
B) nucleus; cytoplasm
C) cytoplasm; cytoplasm
D) cytoplasm; nucleus - CORRECT ANSWER B) nucleus; cytoplasm
True or False. The template strand of DNA for one gene may be the coding strand of DNA for another gene.
A) True
B) False - CORRECT ANSWER A) True
When more than one polypeptide is present in the functioning protein, all of the polypeptides together form the _____.
A) primary structure
B) secondary structure
C) tertiary structure
D) quaternary structure - CORRECT ANSWER D) quaternary structure
The amino acid sequence of a polypeptide chain comprises the ____ structure of the protein.
A) primary
B) secondary
C) tertiary
D) quaternary - CORRECT ANSWER A) primary
Loops, coils and sheets are introduced at the ____ level of protein structure.
A) primary
B) secondary
C) tertiary
D) quaternary - CORRECT ANSWER B) secondary
Interactions between the R groups and water are responsible for the ____ level of protein structure.
A) primary
B) secondary
C) tertiary
D) quaternary - CORRECT ANSWER C) tertiary
The ____ is a multiprotein structure shaped like a barrel through which misfolded proteins pass and are refolded or dismantled.
A) spliceosome
B) lysosome
C) proteasome
D) peroxisome - CORRECT ANSWER C) proteasome
The sugar found in a DNA nucleotide is ____, while the sugar found in an RNA nucleotide is ____.
A) ribose; deoxyribose
B) deoxyribose; ribose
C) glucose; sucrose
D) sucrose; glucose - CORRECT ANSWER B) deoxyribose; ribose
The structure of DNA is ____, while RNA is generally ____.
A) double-stranded; single-stranded
B) single-stranded; double-stranded
C) compact; loose
D) loose; compact - CORRECT ANSWER A) double-stranded; single-stranded
In RNA, uracil forms a complementary base pair with _____.
A) guanine
B) thymine
C) adenine
D) cytosine - CORRECT ANSWER C) adenine
Proteomics _____.
A) is another term for genomics in humans
B) is the study of the collection of proteins produced in a particular cell
C) is the study of proteins produced by a particular gene
D) proves that a single gene codes for only one protein - CORRECT ANSWER B) is the study of the collection of proteins produced in a particular cell
The composition of human hemoglobin _____.
A) remains constant throughout the lifetime of an individual
B) is the same in the embryonic and adult forms
C) always contains two copies of two different subunits
D) decreases in the amount of beta chain as the individual ages - CORRECT ANSWER C) always contains two copies of two different subunits
Fetal hemoglobin _____.
A) carries less oxygen than adult hemoglobin
B) consists mainly of beta chains
C) still makes up a substantial percentage of all hemoglobin at birth
D) differs from adult hemoglobin by the presence of the zeta chain - CORRECT ANSWER C) still makes up a substantial percentage of all hemoglobin at birth
Which statement about pancreatic hormones is NOT true?
A) The endocrine hormones are secreted from a single cell type.
B) The most abundant endocrine cell secretes insulin.
C) Exocrine and endocrine cells derive from a single stem cell type.
D) Glucagon is one of the hormones secreted by endocrine cells. - CORRECT ANSWER A) The endocrine hormones are secreted from a single cell type.
If we look at the relative abundances of different categories of proteins, as we move from the prenatal period to birth and old age _______.
A) the relative expression of transcription factors decreases
B) the relative expression of enzymes decreases
C) the relative expression of transcription factors increases
D) the relative expression of enzymes remains the same - CORRECT ANSWER A) the relative expression of transcription factors decreases
Glucose stimulates the release of the pancreatic hormone ___________.
A) glucagon
B) insulin
C) somatostatin
D) pancreatic polypeptide - CORRECT ANSWER B) insulin
A feature of chromatin remodeling is that _____.
A) it can turn on transcription but cannot silence genes
B) the modified state of chromatin can be passed on when DNA replicates
C) it involves only the addition of methyl groups to DNA
D) it requires RNAi - CORRECT ANSWER B) the modified state of chromatin can be passed on when DNA replicates
Gene expression patterns change over time and in different cell types.
A) True
B) False - CORRECT ANSWER A) True
Enzymes that remove acetyl groups from histone proteins can __________.
A) 1)activate gene transcription
B) 2)shut off gene transcription
C) 3)splice mRNAs
D) 4)block translation - CORRECT ANSWER B) 2)shut off gene transcription
About ______ of the protein-coding genes in humans are regulated by microRNAs.
A) 3/4
B) 2/3
C) 1/2
D) 1/3 - CORRECT ANSWER D) 1/3
Which of the following is not added to histones during chromatin remodeling?
A) acetyl groups
B) methyl groups
C) phosphate groups
D) amino groups - CORRECT ANSWER D) Amino groups
The fact that the modified state of chromatin can be passed on when DNA replicates is an example of ____ inheritance.
A) epistatic
B) Mendelian
C) epigenetic
D) maternal - CORRECT ANSWER C) epigenetic
In humans, there are many fewer genes than there are different proteins produced. This is primarily due to _____.
A) combining different combinations of introns together
B) small interfering RNAs
C) the histone code
D) alternative splicing - CORRECT ANSWER D) Alternative splicing
Which of the following explains how the human genome can have 20,000 genes, but over 200,000 proteins?
A) alternative splicing
B) genes contained within the introns of other genes
C) two proteins cut from one precursor molecule
D) All of the above - CORRECT ANSWER D) All of the above
True or False. Introns for one gene may contain parts of another gene.
A) True
B) False - CORRECT ANSWER A) true
Certain organic chemical groups are added to histone proteins in order to control _____.
A) replication
B) transcription
C) translation
D) splicing - CORRECT ANSWER B) transcription
The _____ is the collection of all the methylated sites in the genome.
A) Proteome
B) Glycome
C) lipidome
D) methylome - CORRECT ANSWER D) methylome
The most abundant type of repeated DNA sequence is _____.
A) transposons
B) pseudogenes
C) centromeres
D) telomeres - CORRECT ANSWER A) transposons
Which statement is true about Alu repeats?
A) The number of Alu repeats has remained constant throughout the history of mankind.
B) There may be as many as 500,000 per genome.
C) They are classified as long interspersed elements.
D) Alu repeats make up as much as 25% of the genome. - CORRECT ANSWER B) There may be as many as 500,000 per genome.
Pseudogenes _____.
A) lead to the production of proteins that have no function
B) may be copies of genes that are no longer used
C) are transcribed into snoRNAs
D) are very rare in the human genome - CORRECT ANSWER B) may be copies of genes that are no longer used
Genes for tRNA _____.
A) make up about 10% of the human genome
B) are scattered randomly around the human genome
C) account for 0.1% of the human genome
D) are all transcribed equally in all cell types - CORRECT ANSWER C) account for 0.1% of the human genome
Which of the following is NOT an example of a repeated sequence?
A) pseudogenes
B) telomeres
C) centromeres
D) transposons - CORRECT ANSWER A) pseudogenes
Which of the following is an example of a noncoding (nc) RNA?
A) pseudogenes
B) tRNA
C) rRNA
D) All of the above - CORRECT ANSWER D) all of the above
Only ____ of the human genome encodes protein.
A) 1.5 percent
B) 15 percent
C) 5.5 percent
D) 55 percent - CORRECT ANSWER A) 1.5 percent
Most of the human genome does not encode protein. The rest of the genome includes _____.
A) noncoding RNAs
B) introns
C) promoters
D) All of the above - CORRECT ANSWER D) All of the above
About _____ percent of all human genes are alternately spliced.
A) 27
B) 10
C) 5
D) 90 - CORRECT ANSWER D) 90
A ____ mutation occurs during the DNA replication that precedes meiosis, while a ____ mutation occurs during the DNA replication that precedes mitosis.
A) germline; somatic
B) germline; spontaneous
C) somatic; germline
D) spontaneous, point - CORRECT ANSWER A) germline; somatic
Which of the following diseases is caused by "exon skipping" in a gene encoding enzyme necessary for the survival of certain neurons?
A) beta thalassemia
B) Ehlers-Danlos syndrome
C) cystic fibrosis
D) familial dysautonomia - CORRECT ANSWER D) familial dysautonomia
Beta thalassemia and sickle cell disease are both associated with mutations in the ____ gene.
A) globin
B) dystrophin
C) collagen
D) CCR5 - CORRECT ANSWER A) globin
Which of the following diseases is associated with a collagen-related mutation?
A) Ehlers-Danlos syndrome
B) aortic aneurysm
C) osteogenesis imperfecta
D) All of the above - CORRECT ANSWER D) all of the above
Collagen is a major component of _____.
A) nervous tissue
B) muscle tissue
C) connective tissue
D) epithelial tissue - CORRECT ANSWER C) connective tissue
A spontaneous mutation usually originates as an error in _____.
A) DNA replication
B) DNA transcription
C) translation
D) reverse transcription - CORRECT ANSWER A) DNA replication
The ____ gene has a very high mutation rate, arising in 40 to 100 of every million gametes.
A) Huntington disease
B) Marfan syndrome
C) neurofibromatosis type 1
D) osteogenesis imperfecta - CORRECT ANSWER C) neurofibromatosis type 1
____ codons are those that specify the same amino acid.
A) Nonsynonymous
B) Conditional
C) Triplet repeat
D) Synonymous - CORRECT ANSWER D) Synonymous
Small additions and deletions of DNA bases are more likely to occur near ____, whose sequences read the same on complementary strands.
A) transposons
B) tautomers
C) palindromes
D) minisatellites - CORRECT ANSWER C) palindromes
A ____ mutation is intentionally caused, changing a gene in a desired way.
A) spontaneous
B) somatic
C) site-directed
D) conditional - CORRECT ANSWER C) site-directed
A mutagen is _____.
A) an agent that causes a mutation
B) a change in the nucleotide base sequence
C) an unusual phenotype
D) None of the above - CORRECT ANSWER A) an agent that cases a mutation
The Ames test _____.
A) isolates mutational hot spots in the genome
B) tests the mutagenicity of a substance
C) is involved in site-directed mutagenesis
D) examines the rate of sickle cell disease in a population - CORRECT ANSWER B) tests the mutagenicity of a substance
Which of the following is a natural source of radiation?
A) sunlight
B) cosmic rays
C) radioactive minerals in the Earth's crust
D) All of the above - CORRECT ANSWER D) all of the above
A point mutation that changes a codon specifying an amino acid into a stop codon is called a _____.
A) missense mutation
B) nonsense mutation
C) frameshift mutation
D) deletion mutation - CORRECT ANSWER B) a nonsense mutation
Fragile_X syndrome and myotonic dystrophy are caused by a(n) _____.
A) tandem duplication
B) fusion gene
C) expanding triplet repeat
D) deletion - CORRECT ANSWER C) expanding triplet repeat
Which of the following is an effect of a mutation?
A) It prevents a protein from forming.
B) It lowers the amount of a protein.
C) It adds a function to a protein.
D) All of the above can occur. - CORRECT ANSWER D) all of the above can occur
Changing the codon AGC to AGA represents a ____ mutation.
A) missense
B) nonsense
C) frameshift
D) deletion - CORRECT ANSWER A) missense
A point mutation that alters a codon so that the encoded amino acid is substituted with another is called a ____ mutation.
A) silent
B) missense
C) nonsense
D) transversion - CORRECT ANSWER B) missense
A frameshift mutation _____.
A) replaces one amino acid with another
B) removes part of the protein
C) introduces a section of amino acids not normally found
D) joins two different proteins - CORRECT ANSWER C) introduces a section of amino acids not normally found
Fatal familial insomnia is an example of a(n) _____.
A) expanding repeat disorder
B) deletion mutation
C) fusion gene
D) prion disorder - CORRECT ANSWER D) prion disorder
Which of the following is an example of a conditional mutation?
A) Fragile-X syndrome
B) Creutzfeldt-Jakob syndrome
C) myotonic dystrophy
D) G6PD deficiency - CORRECT ANSWER D) G6PD deficiency
A ____ mutation affects the phenotype only under certain conditions.
A) spontaneous
B) somatic
C) site-directed
D) conditional - CORRECT ANSWER D) conditional
During DNA repair, photoreactivation or excision repair can correct _____.
A) mismatched bases
B) pyrimidine dimers
C) broken sugar-phosphate backbones
D) conditional mutants - CORRECT ANSWER B) Pyrimidine dimers
Which of the following defects causes ataxia telangiectasis?
A) deficiency in kinase that controls the cell cycle
B) deficient excision repair
C) deficient mismatch repair
D) inactive ligase that slows replication - CORRECT ANSWER A) deficiency in kinase that controls the cell cycle
____ are chemicals or radiation that increase the risk of mutation.
A) Proteins
B) Fusions genes
C) Carcinogens
D) Mutagens - CORRECT ANSWER D) mutagens
point mutation that has no obvious effect at all on the phenotype is called a ____ mutation.
A) silent
B) missense
C) nonsense
D) transversion - CORRECT ANSWER A) silent
The field of genetics that studies the relationship between chromosome variations and specific traits is called _____.
A) Mendelian genetics
B) cytogenetics
C) quantitative genetics
D) behavioral genetics - CORRECT ANSWER B) cytogenetics
A(n) ____ chromosome has its centromere near a tip so that it has one long arm and one very short arm.
A) metacentric
B) submetacentric
C) acrocentric
D) None of the above - CORRECT ANSWER C) acrocentric
The structure associated with the centromere that contacts the spindle fibers during mitosis is the _____.
A) alpha satellite repeat
B) subtelomere
C) euchromatin
D) kinetochore - CORRECT ANSWER D) kinetochore
____ contains more protein-encoding sequences than ____.
A) Heterochromatin; euchromatin
B) Euchromatin; heterochromatin
C) Pericentric inversions; aneuploids
D) Aneuploids; pericentric inversions - CORRECT ANSWER B) Euchromatin; heterochromatin
Our closest evolutionary relative, according to karyotypes analysis, is the _____.
A) mouse
B) domestic cat
C) gorilla
D) pygmy chimpanzee (bonobo) - CORRECT ANSWER D) pygmy chimpanzee
Heterochromatic regions at the ends of chromosomes are called _____.
A) centromeres
B) euchromatin
C) telomeres
D) satellites - CORRECT ANSWER C) telomeres
Some human chromosomes contain _____, which are bloblike ends that extend from a thinner stalklike bridge from the rest of the chromosome.
A) centromeres
B) kinetochores
C) telomeres
D) satellites - CORRECT ANSWER D) satellites
The schematic map of a chromosome is called a(n) _____.
A) karyotype
B) ideogram
C) anagram
D) chromogram - CORRECT ANSWER B) ideogram
An individual with the chromosomal description 45, X would be a _____.
A) normal female
B) female with Turner syndrome
C) male with Klinefelter syndrome
D) Cannot be determined - CORRECT ANSWER B) female with turner syndrome
Prenatal diagnostic techniques that obtain fetal chromosomes include all of the following EXCEPT _____.
A) amniocentesis
B) fetal cell sorting
C) chorionic villus sampling
D) fluorescence (ital)in situ(/ital) hybridization - CORRECT ANSWER D) fluorescence (ital)in situ(/ital) hybridization
Which of the following procedures uses fetal cells that are obtained from the mother's bloodstream?
A) amniocentesis
B) fetal cell sorting
C) chorionic villus sampling
D) fluorescence in situ hybridization - CORRECT ANSWER B) fetal cell sorting
Which of the following utilizes labeled DNA probes?
A) amniocentesis
B) fetal cell sorting
C) chorionic villus sampling
D) fluorescence (ital)in situ(/ital) hybridization - CORRECT ANSWER D) fluorescence (ital)in situ(/ital) hybridization
In _____ the karyotype of a villus cell differs from that of an embryo cell.
A) Robertsonian translocation
B) reciprocal translocation
C) male nondisjunction
D) chromosomal mosaicism - CORRECT ANSWER D) chromosomal mosaicism
An individual with two normal sets of autosomes and a single X chromosome has _____.
A) Down syndrome
B) Patau syndrome
C) Turner syndrome
D) Klinefelter syndrome - CORRECT ANSWER C) Turner syndrome
The most common autosomal aneuploid is _____.
A) trisomy 13
B) trisomy 15
C) trisomy 18
D) trisomy 21 - CORRECT ANSWER D) trisomy 21
In nondisjunction, which parent leads to the sex chromosome aneuploid XYY?
A) mother
B) father
C) either parent
D) both parents - CORRECT ANSWER B) father
A triploid human karyotype has how many chromosomes?
A) 23
B) 46
C) 69
D) 92 - CORRECT ANSWER C) 69
Nondisjunction of chromosome 21 during meiosis II in human females can result in all of the following chromosome complements in a zygote except _____. (Assume the oocyte is fertilized by a sperm with a normal chromosome set.)
A) no chromosome 21
B) euploid for chromosome 21
C) monosomic for chromosome 21
D) trisomic for chromosome 21 - CORRECT ANSWER A) no chromosome 21
About 90% of trisomy 21 Down conceptions are due to nondisjunction during _____.
A) meiosis I in the female
B) meiosis II in the female
C) meiosis I in the male
D) meiosis II in the male - CORRECT ANSWER A) meiosis I in the female
Approximately ____ percent of spontaneous abortions result from extra or missing chromosomes.
A) 10
B) 25
C) 50
D) 75 - CORRECT ANSWER C) 50
How many chromosomes does a person with Edward syndrome have?
A) 45
B) 46
C) 47
D) 48 - CORRECT ANSWER C) 47
All of the following aneuploids can result from female nondisjunction except _____.
A) Klinefelter syndrome
B) triplo-X
C) Turner syndrome
D) Jacobs syndrome - CORRECT ANSWER D) Jacobs syndrome
In a(n) ____, the short arm of two acrocentric chromosomes break, and the long arms join forming a single large chromosome with two long arms.
A) Robertsonian translocation
B) reciprocal translocation
C) inversion
D) duplication - CORRECT ANSWER A) Robertsonian translocation
Cri-du-chat syndrome is associated with _____.
A) a missing chromosome number 5
B) an additional chromosome number 5
C) a deletion of the long arm of chromosome number 5
D) a deletion of the short arm of chromosome number 5 - CORRECT ANSWER D) a deletion of the short arm of chromosome number 5
When chromatids divide along the wrong plane, structures with identical arms called ____ are formed.
A) ring chromosomes
B) translocations
C) isochromosomes
D) satellites - CORRECT ANSWER C) isochromosomes
Consider the following normal sequence of genes: a b c d e f g h. The sequence a b f e d c g h represents a(n) _____.
A) deletion
B) duplication
C) inversion
D) translocation - CORRECT ANSWER C) inversion
Which of the following karyotypes is NOT possible in the offspring of a translocation carrier (involving chromosomes 14 and 21) and a normal individual?
A) deficient 14 or deficient 21
B) normal
C) translocation Down syndrome
D) all are possible outcomes. - CORRECT ANSWER D) all are possible
An inversion that includes the centromere is called _____.
A) pericentric
B) paracentric
C) Robertsonian
D) lethal - CORRECT ANSWER A) Pericentric
A couple seeks testing and counseling after they have a child with cystic fibrosis. Testing reveals that the mother is a carrier, but the father is not. How can these results be explained?
A) The man tested is not the biological father.
B) A mutation altered the child's normal allele.
C) Uniparental disomy (from the mother).
D) All are possible explanations; additional testing is needed. - CORRECT ANSWER D) All are possible, we need testing
A chromosome is ____ if the centromere divides it into two arms of approximately equal length.
A) telocentric
B) submetacentric
C) metacentric
D) acrocentric - CORRECT ANSWER C) metacentric
The centromere generally divides the chromosome into a ____ p arm and a ____ q arm.
A) shorter; longer
B) longer; shorter - CORRECT ANSWER A) shorter; longer
The tips of chromosomes contain repeated sequences that shorten with each mitotic division. These regions are called _____.
A) p arms
B) centromeres
C) q arms
D) telomeres - CORRECT ANSWER D) telomeres
____ cells have extra or missing chromosomes, while ____ cells contain a normal number of chromosomes.
A) Aneuploid; euploid
B) Polyploid; autosomal
C) Autosomal; polyploid
D) Euploid; aneuploid - CORRECT ANSWER A) Aneuploid; euploid
____ is a common cause of aneuploidy resulting in a gamete with one extra chromosome and another gamete with one missing chromosome.
A) Chromosome pairing
B) Nondisjunction
C) Segregation
D) Replication - CORRECT ANSWER B) nondisjunction
The alleles in a population comprise its _____.
A) gene allocation
B) gene flow
C) gene pool
D) genotype - CORRECT ANSWER C) gene pool
____ is the source of new alleles in a population.
A) Genetic drift
B) Mutation
C) Selection
D) Nonrandom mating - CORRECT ANSWER B) Mutation
Small scale shifts in allele frequencies is the defining characteristic of _____.
A) microevolution
B) macroevolution
C) natural selection
D) nonrandom mating - CORRECT ANSWER A) microevolution
Hardy-Weinberg equilibrium explains _____.
A) the introduction of new alleles into a population.
B) the formation of a new species.
C) the reasons for migration.
D) constant allele frequencies in a population. - CORRECT ANSWER D) constant allele frequencies in a population
Consider a gene in a population where the dominant allele G occurs in 56% of the gametes. What is the frequency of the recessive allele?
A) 56%
B) 44%
C) 0%
D) Cannot be determined - CORRECT ANSWER B) 44%
Assuming Hardy-Weinberg equilibrium, what percentage of individuals are heterozygous if p = 0.6?
A) 16%
B) 24%
C) 35%
D) 48% - CORRECT ANSWER D) 48%
Approximately 1/2000 individuals have a recessive genetic disorder. What is the frequency of the recessive allele?
A) 0.0005
B) 0.995
C) 0.978
D) 0.022 - CORRECT ANSWER D) 0.022
Which of the following represents the proportion of individuals within a population displaying a dominant phenotype?
A) p2
B) 2pq
C) p2 + 2pq
D) p2 + 2pq + q2 - CORRECT ANSWER C) p2 + 2pq
In a population in Hardy-Weinberg equilibrium, the frequency of a recessive allele will ____ over time.
A) increase
B) decrease
C) remain the same
D) vary - CORRECT ANSWER C) Remain the same
Assume that the incidence of an X-linked recessive disorder is 1 in 200 male births. What is the frequency of the mutant allele?
A) 0.000025
B) 0.005
C) 0.071
D) 0.995 - CORRECT ANSWER B) 0.005
Again assuming that an X-linked recessive disorder occurs in 1 in 200 male births, what is the frequency of affected females?
A) 0.000025
B) 0.005
C) 0.071
D) 0.995 - CORRECT ANSWER A) 0.000025
Assume that the incidence of an X-linked recessive disorder is 1 in 200 female births. What is the frequency of the mutant allele?
A) 0.000025
B) 0.005
C) 0.071
D) 0.995 - CORRECT ANSWER C) 0.071
Again assuming that an X-linked recessive disorder occurs in 1 in 200 female births, what is the frequency of affected males?
A) 0.000025
B) 0.005
C) 0.071
D) 0.995 - CORRECT ANSWER C) 0.071
The chance of carrying the cystic fibrosis allele is 1/23 in the Caucasian population. For two unrelated Caucasian individuals with no family history of CF, the risk of having an affected child is _____.
A) 1/4 x 1/4
B) 1/23 x 1/23 x 1/4
C) 1/23 x 1/23
D) 1/4 x 1/4 x 1/23 - CORRECT ANSWER B) 1/23 x 1/23 x 1/4
The Mennonite and Amish populations have many autosomal recessive illnesses that are extremely rare elsewhere. Which of the following factors is NOT a cause?
A) They descended from a few founding families.
B) They marry among themselves.
C) Spontaneous mutations occur at a very high rate.
D) All of the above account for the prevalence of recessive disorder. - CORRECT ANSWER C) Spontaneous mutations occur at a very high rate
Given that cystic fibrosis affects 1 in 2000 Caucasian newborns, what is the frequency of the recessive allele for cystic fibrosis in the population?
A) 0.0005
B) 0.025
C) 0.022
D) 0.978 - CORRECT ANSWER C) 0.022
Using the information from Question 17, what is the carrier frequency in the population?
A) 0.043
B) 0.025
C) 0.022
D) 0.978 - CORRECT ANSWER A) 0.043
Using the information from questions 17 and 18, what is the chance that two Caucasian individuals with no family history of cystic fibrosis will produce a child with cystic fibrosis?
A) 0%
B) 1 in 4
C) 1 in 529
D) 1 in 2116 - CORRECT ANSWER D) 1 in 2116
In a recent case, a professor accused of murder was exonerated when it was shown that when he and his wife shared a towel earlier in the morning, his skin cells had been transferred to her face. Later, when the murderer touched her face, he picked up the husband's cells and transferred them to his weapon. This is an example of _____.
A) polymorphism
B) primary transfer
C) secondary transfer
D) a familial DNA search - CORRECT ANSWER C) secondary transfer
The differences in DNA fragment sizes resulting from differences in restriction enzyme cutting sites are called _____.
A) polymorphisms
B) VNTRs
C) STRs
D) RFLPs - CORRECT ANSWER D) RFLPs
Short sequences of DNA can be amplified by _____ before they are analyzed.
A) RFLP
B) STR
C) PCR
D) None of the above; small sequences are not used in DNA analysis. - CORRECT ANSWER C) PCR
The ____ rule is used to calculate the likelihood that someone other than the suspect in a forensic case may have left the crime scene sample.
A) sum
B) product
C) additive
D) None of the above; probability is not used to calculate matches. - CORRECT ANSWER B) product
Electrophoresis separates DNA fragments of different sizes with ____ fragments moving faster to the ____ pole.
A) shorter; negative
B) shorter; positive
C) longer; negative
D) longer; positive - CORRECT ANSWER B) shorter; positive
DNA collected from a crime scene and from a suspect both have the following genotype: A1 A2 B2 C1 C2. If the frequencies of the A1, B1, and C1 alleles are 0.9, 0.99, and 0.8 respectively, calculate the probability that another person in the suspect's group has the same pattern of these alleles.
A) 1.44 x 10-6
B) 5.76 x 10-6
C) 0.400
D) 0.600 - CORRECT ANSWER B) 5.76 x 10-6
Who was the first person in the United States to be convicted of a crime on the basis of DNA evidence?
A) Nancy Hodge
B) Alec Jeffreys
C) Lonnie David Franklin Jr.
D) Tommie Lee Andrews - CORRECT ANSWER D) Tommie Lee Andrews
Which of the following is INCORRECT regarding VNTRs?
A) They are also called microsatellites.
B) Their distribution in the genome is not uniform.
C) The repeat length is 10-80 bases.
D) All of the above are correct. - CORRECT ANSWER A) They are also called microsatellites
Which of the following is best used in cases when the DNA of the victim is highly fragmented?
A) RFLPs
B) STRs
C) VNTRs
D) None of the above can be used. - CORRECT ANSWER B) STRs
The use of copy number variants of very short repeats to identify or distinguish individuals is called _____.
A) biotargeting
B) DNA profiling
C) bioethics
D) biostatistics - CORRECT ANSWER B) DNA profiling
The Hardy-Weinberg equilibrium is best described as _____.
A) the ratio of genotype classes expected in the progeny of a particular cross
B) a biotechnology that detects differences in the number of copies of certain DNA repeats among individuals
C) an idealized state in which allele frequencies in a population do not change from generation to generation
D) the number of new cases of a disease during a certain time in a particular location - CORRECT ANSWER C) an idealized state in which allele frequencies in a population do not change from generation to generation
Macroevolution describes _____.
A) genetic change sufficient to form a new species
B) the change of allele frequency in a population
C) a characteristic associated with increased likelihood of developing a particular medical condition
D) all the alleles in a given population - CORRECT ANSWER A) genetic change sufficient to form a new species
Challenges to DNA profiling in mass disasters include _____.
A) climate conditions that hasten decay
B) lack of relatives
C) poor DNA quality
D) All of the above - CORRECT ANSWER D) All of the above
A(n) ____ is a group of interbreeding members of the same species in a particular area.
A) frequency
B) incidence
C) population
D) equilibrium - CORRECT ANSWER C) Population
Which of these criteria must be met for a biobank to be effective?
A) have data and tissue samples from at least 1000 people
B) include family trees that link generations
C) draw conclusions based on data from one or two families
D) assume that all traits in the population are in Hardy-Weinberg equilibrium - CORRECT ANSWER B) include family trees that link generations [Show Less]