PCB3063 Final Exam Review
A somatic cell in G1 of interphase has 12 chromosomes. How many pairs of chromosomes will be found per cell after cytokinesis of meiosis II?
0
An egg cell of a certain organism has 8 chromosomes. How many DNA molecules will be found per cell when this cell is at metaphase I of meiosis?
16
The diploid number of a cell is 12. How many DNA molecules will be found per cell when this cell is in G2?
24
A cell has 16 chromosomes at S phase. How many DNA molecules will be found per cell when this cell is just after anaphase I of meiosis I?
32
If a sample of double stranded DNA is found to have 18% guanine, the expected amount of adenine in this sample is: A. 18% B. 25% C. 32% D. 36% E. You can not tell from this information alone.
32%
A skin cell for a certain organism has 24 chromosomes. How many DNA molecules will be found per cell when this cell is at prophase of mitosis?
48
A somatic cell in G1 of interphase has 10 chromosomes. How many chromosomes will be found per cell after cytokinesis of meiosis I?
5
A somatic cell in G1 of interphase has 52 chromosomes. How many chromosomes will be found per cell when this cell is in G2?
52
In a cross of 4 independently assorting genes, the parents' genotypes are: AABBCcDd (parent #1) x aabbCcdd (parent #2). What is the chance one of their offspring would have the same genotype as parent #2 (i.e. aabbCcdd)? A. 0 B. 1/4 C. 1/2 D. 1
A. 0
In individual with Turner's System would have _____ Barr bodies in her somatic cells. A. 0 B. 1 C. 2 D. 4
A. 0
In chickens, there is a Z-linked recessive disease that causes blindness. If a female chicken who is blind is mated with a male who is homozygous dominant for the disease, what percentage of female offspring will be blind? (Hint: Remember that in chickens, ZW is a female while ZZ is a male.) A. 0% B. 25% C. 50% D. 100%
A. 0%
In a certain population, a particular recessive condition occurs in 1 out of 400 individuals. What is the frequency of the recessive allele in this population? A. 0.05 B. 0.0025 C. 0.025 D. 0.5 E. 0.95
A. 0.05
Assuming the population is in Hardy-Weinberg equilibrium, consider this question: You are a carrier of a recessive trait that is expressed in only 1% of the population. What is the probability that your classmate is also a carrier? A. 0.18 B. 0.9 C. 0.81 D. 0.1
A. 0.18
Phenylketonuria (PKU) is an autosomal recessive disease which causes the inability to break down certain amino acids and can create significant mental delays if patients do not follow special diets. The incidence of PKU in the general population is 1 out of 10,000 people. What is the frequency of the dominant allele (p) in the general population? Assume there are only 2 alleles, the mutated PKU recessive and the wildtype dominant, and that the population is in Hardy-Weinberg equilibrium. A. 0.99 B. 0.98 C. 0.0001 D. 0.01
A. 0.99
How many Barr bodies would you expect to find in the somatic cells of a Kleinfelter's male? A. 1 B. 3 C. 2 D. 0
A. 1
Wild horses can have short or long manes and brown or green eyes. Mane phenotype is controlled by a single gene with two alleles, M (long mane) and m (short mane), where M is dominant to m. The eye phenotype is also controlled by a single gene with two alleles, B (brown eyes) and b (green eyes), where B is dominant to b. The mane and eye phenotype genes assort independently. In the cross MmBb x mmBb, what is the probability of a foal having a short mane and green eyes? A. 1/8 B. 1/4 C. 1/16 D. 1/2
A. 1/8
A mammalian species has 32 total chromosomes (2n=32). Females have two X-chromosomes and males have one X and one Y chromosome. A normal female (XX) of this species would have ______ linkage groups. A. 16 B. 15 C. 17 D. 32
A. 16
List the following events of pre-mRNA splicing in the correct order: (1) Exons are joined and introns released as lariats (2) U1 attaches to the 5' splice site (3) A U4, U5, and U6 complex joins the spliceosome (4) U2 attaches to the branch point (5) U1 and U4 are released A. 2, 4, 3, 5, 1 B. 2, 3, 1, 4, 5 C. 4, 2, 3, 5, 1 D. 4, 2, 5, 3, 1 E. 3, 4, 2, 5, 1
A. 2, 4, 3, 5, 1
An organism has a diploid number of 24. A non-disjunction event occurs during meiosis I in a female of this species and an egg from that round of meiosis is fertilized by a normal sperm. What are the possible chromosome numbers for an offspring resulting from this fertilization? A. 23 or 25 only B. 25 only C. 23 only D. 23, 24, or 25
A. 23 or 25 only
If a DNA molecule that is 50 base pairs long contains 15 cytosine bases (C), how many thymine bases will it have? A. 35 B. 30 C.15 D. 10
A. 35
A human with a XO sex chromosome genotype would have a diploid number of ____ and would appear phenotypically as _______. A. 45/female B. 45.male C. 46/male D. 47/female
A. 45/female
What RNA sequence is transcribed if the DNA non-template strand is the following? 5' C A G G T T A C G C T 3' A. 5' C A G G U U A C G C U 3' B. 3' C A G G U U A C G C U 5' C. 5' G U C C A A U G C G A 3' D. 3' G U C C A A U G C G A 5'
A. 5' C A G G U U A C G C U 3'
If the sequence of an RNA transcript is 5'-GGCAUCGACG-3', what is the sequence of its non-template strand of DNA? A. 5'-GGCATCGACG-3' B. 3'-CCGTAGCTGC-5' C. 3'-GGCATCGACG-5' D. 5'-CCGTAGCTGC-3'
A. 5'-GGCATCGACG-3'
If the mother is a carrier (heterozygote) for red-green color blindness and the father is not red-green colorblind, what percentage of her sons could be affected? A. 50% B. 100% C. 25% D. 75% E. 0%
A. 50%
The recessive disease cystic fibrosis occurs in 16 out of 10,000 individuals in the United States. Using the Hardy-Weinberg equation, what is the percentage of heterozygotes for cystic fibrosis in the US? A. 7.68% B. 92.16% C. 0.16% D. 0.04%
A. 7.68%
Testcross: Aa Bb Cc x aa bb cc ABC 580 abc 592 ABc 45 abC 40 AbC 89 aBc 94 aBC 3 Abc 5 Total: 1448 What gene is in the middle? A. A B. B C. C
A. A
Linked genes A and B have a recombination frequency of 12%. Linked genes A and C have a recombination frequency of 25%. Which gene pair is closer together on the chromosome based on this data alone? A. A and B B. B and C C. A and C
A. A and B
On what site on the ribosome do the tRNA's (other than the initiator carrying methionine) bearing amino acids bind? A. A site B. P site C. E site
A. A site
Possible genotypes for the parents in the P generation of Mendel's classic monohybrid crosses could be _________ A. AA x aa. B. AA x AA C. aa x aa. D. Aa x Aa.
A. AA x aa.
A woman with Type AB blood has a child with a man with homozygous Type B blood and the child has Type O blood. Assuming the Type O child is truly their biological child, what are the possible genotypes for the Type O child? (Note: Due to formatting issues in Webcourses' Quiz answer options, the genotypes such as IAIB will be shown as AB.) A. ABhh or BBhh B. ABhh only C. BBhh only D. iiHh only E. iiHH or iiHh
A. ABhh or BBhh
In a trihybrid cross between the following 2 parents, what are the possible gametes parent #1 can produce? AAbbCc (parent 1) x AABbCc (parent 2) A. AbC or Abc B. Abc only C. ABC or ABc or AbC or Abc D. AabbCc E. AbC only
A. AbC or Abc
Familial precocious puberty is an autosomal dominant trait which causes males to undergo very early puberty, often by the age of 5. Females who possess the trait do NOT undergo early puberty. A male who is heterozygous for this trait has children with a woman who is homozygous dominant. What would be the expected phenotypes by sex of their children? A. All males will have precocious puberty and none of the females will. B. None of the males will have precocious puberty and all of the females will. C. None of the offspring, male or female, will have precocious puberty. D. All of the offspring, male and female, will have precocious puberty.
A. All males will have precocious puberty and none of the females will.
In a species of birds, there is an autosomal maternally influenced gene that has 2 alleles, one allele (L) is responsible for making large sized chicks and the other allele (l) causes small sized chicks. The size of the chicks is determined by whether or not their mother is capable of producing a protein herself that is deposited in the developing eggs. If two heterozygous parents (Ll) are mated, what would be the expected phenotypes of their offspring? A. All of the offspring will be large sized. B. None of the offspring will be large sized. C. 1/2 of the offspring will be large sized and 1/2 will be small sized. D. 3/4 of the offspring will be large sized and 1/4 will be small sized.
A. All of the offspring will be large sized.
A gene that contributes to birth weight is known to be influenced by a maternal effect. A dominant allele (L) contributes to large birth weights while the recessive allele (l) produces lower weight babies. In this case, the mother produces a gene product based on her genotype into the uterus which influences the birth weight of her babies. Two heterozygotes (Ll) have children. What is the expected phenotypes of their offspring? A. All offspring will have large birth weights. B. All offspring will have low birth weights. C. 1/2 of the offspring will have large birth weights and 1/2 will have low birth weights. D. 3/4 of the offspring will have large birth weights and 1/4 will have low birth weights.
A. All offspring will have large birth weights.
Which of the following would be FALSE about a disorder inherited through mitochondrial DNA? A. An individual can inherit it from their father. B. The disorder could show widely variable phenotype patterns between different cell types due to random distribution of mitochondria during early cell division. C. Males and females can be affected by the disorder. D. Reciprocal crosses will show different results between the sexes.
A. An individual can inherit it from their father.
Which of the following would be FALSE about a disorder inherited through mitochondrial DNA? A. An individual can inherit it from their father. B. The disorder could show widely variable phenotype patterns between different cell types due to random distribution of mitochondria during early cell division. C. Males and females can be affected by the disorder. D. Reciprocal crosses will show different results between the sexes.
A. An individual can inherit it from their father.
Which of the following statements about bacterial transcription is TRUE? A. Bacterial transcripts include the Shine-Dalgarno sequence. B. Transcription and translation must take place in different locations in bacterial cells. C. The 5′ and 3′ ends of mRNA transcripts are modified in bacteria. D. Most bacterial genes contain a large number of introns.
A. Bacterial transcripts include the Shine-Dalgarno sequence.
The recombination frequencies between 3 linked genes (A, B, C) has been calculated as follows: AC 5% CB 15% AB 20% Which of the following could be the order of these 3 genes along the chromosome? A. Both ACB and BCA B. Both CBA and ABC C. BCA only D. ACB only
A. Both ACB and BCA
The recombination frequencies between 4 linked genes (A, B, C and D) has been calculated as follows: AC 24% CB 5% BD 7% AD 12% CD 12% Which of the following could be the order of these 4 genes along the chromosome? A. CBDA B. CDBA C. DBCA D. ABDC E. BADC
A. CBDA
Which of the following best demonstrates the Central Dogma of molecule biology? A. DNA > RNA > Protein B. RNA > DNA > Protein C. Protein > DNA > RNA D. Protein > RNA > DNA E. DNA > Protein > RNA
A. DNA > RNA > Protein
Over evolutionary time, DNA replaced RNA as the primary molecule holding the code for genetic information because DNA is believed to be more chemically stable. Which attribute of DNA is the reason behind its chemical stability? A. DNA lacks a free hydroxyl group on the 2′-carbon atom of its sugar. B. Unlike RNA, DNA is usually double-stranded. C. DNA does not usually form hairpin loops. D. One of the two pyrimidines found in DNA does not involve uracil. E. DNA contains thymines, which make it more chemically stable.
A. DNA lacks a free hydroxyl group on the 2′-carbon atom of its sugar.
A cell with defective __________ would not be able to join Okasaki fragments or seal repaired DNA segments. A. DNA ligase B. helices C. primate D. DNA polymerase E. nuclease
A. DNA ligase
Which of the following is an appropriate description of a nucleosome? A. DNA wrapped around a histone octamer B. DNA wrapped around a kinectochore octamer C. DNA wrapped around a shelterin octamer D. DNA wrapped around a binding protein octamer E. DNA wrapped around a histone octamer + linker DNA
A. DNA wrapped around a histone octamer
Which of the following is an appropriate description of a nucleosome? A. DNA wrapped around a histone octamer B. DNA wrapped around a kinectochore octamer C. DNA wrapped around a shelterin octamer D. DNA wrapped around a binding protein octamer E. DNA wrapped around a histone octamer + linker DNA
A. DNA wrapped around a histone octamer
A mutation which causes a cell's EF-Ts to be less functional would have what DIRECT effect? A. EF-Tu would not be regenerated during the elongation process of translation. B. Translocation of the ribosome would not occur. C. EF-Tu would not be regenerated during the elongation process of transcription. D. tRNAs would not become charged with amino acids.
A. EF-Tu would not be regenerated during the elongation process of translation.
What is the difference between euchromatin and heterochromatin? A. Euchromatin is decondensed early in the cell cycle, whereas heterochromatin remains highly condensed. B. Euchromatin contains methylated cytosines; Heterochromatin lacks methlyated cytosines. C. Euchromatin decondenses to form DNA without histones; Heterochromatin remains packaged with histones at all times. D. Euchromatin is almost never transcribed; Most transcription takes place in heterochromatin.
A. Euchromatin is decondensed early in the cell cycle, whereas heterochromatin remains highly condensed.
For the same scenario described in question #6, which statement is accurate? A. Genetic variation has increased in Population B. B. Genetic variation has decreased in both populations. C. Genetic variation has stayed the same in both populations. D. Genetic variation has increased between the populations.
A. Genetic variation has increased in Population B.
Which of the following statements about human sex determination is TRUE based on what we know from sex chromosome aneuploidies? A. In absence of Y chromosome, female development occurs. B. Extra copies of X has no affect on development in both sexes. C. A male with a non-functioning SRY gene will still be phenotypically male if he has a Y chromosome. D. Genes affecting fertility found only on the X chromosome. E. Presence of Y chromosome is female determining.
A. In absence of Y chromosome, female development occurs.
Mutation has what effect on populations? A. It creates or increases potential genetic variation. B. It allows fixation to occur. C. It reduces genetic variation. D. It creates Hardy-Weinberg equilibrium. D. It makes populations less likely to evolve.
A. It creates or increases potential genetic variation.
Jane has an X-linked recessive disease (i.e. She has the recessive phenotype). Which of the following would be a true statement about how Jane inherited this disease? A. Jane's paternal grandmother (i.e. Jane's dad's mom) either had the disease or was a heterozygote for this disease. B. Jane's mother must also have the disease. C. Only Jane's father has the recessive allele. D. Only Jane's mother has the recessive allele. E. Jane's father can not have the disease.
A. Jane's paternal grandmother (i.e. Jane's dad's mom) either had the disease or was a heterozygote for this disease.
Consider this statement: Pea plants carry two copies of the gene for flower color but their gametes only have one copy. This statement is an application of Mendel's __________ A. Law of segregation. B. Law of independent Assortment. C. idea that genes come in different versions. D. concept of dominant and recessive alleles.
A. Law of Segregation .
Three women give birth to babies on the same day at the same hospital. In a terrible mistake, the three babies are mixed up in the nursery so that the nurses do not know for sure which baby belongs to which mom. The hospital determines the blood types of all the parents and babies. Mom #1 and her husband both have Type A. Mom #2 has Type AB and her husband has Type B. Mom #3 and her husband both have Type O. Baby X has Type O blood. Baby Y has Type A. Baby Z has Type B. The nurses now know which baby belongs to which mom. Which combination is correct? (Note: There is NO Bombay Phenotype occurring with any of these parents or babies.) A. Mom #1 had Baby Y, Mom #2 had Baby Z and Mom #3 had Baby X. B. Mom #1 had Baby Z, Mom #2 had Baby Y and Mom #3 had Baby X C. Mom #1 had Baby X, Mom #2 had Baby Z and Mom #3 had Baby Y D. Mom #1 had Baby X, Mom #2 had Baby Y and Mom #3 had Baby Z
A. Mom #1 had Baby Y, Mom #2 had Baby Z and Mom #3 had Baby X.
In the Hershey and Chase experiment, if the radioactive sulfur had been found inside the bacteria rather than the radioactive phosphorus, what conclusion would they have made? A. Proteins are the molecules that encode heredity. B. DNA is the molecule that encodes heredity. C. RNA is the molecule that encodes heredity. D. Both RNA and DNA are molecules that could encode heredity. E. This result does not show any evidence for what molecule encodes heredity.
A. Proteins are the molecules that encode heredity.
Match the correct human sex chromosome aneuploidy with the correct statement. XXY A. Sterile male with feminine characteristics B. Fatal C. Only known human viable monosomy D. Phenotypically fertile females E. Phenotypically fertile male
A. Sterile male with feminine
If the "branch point" of an intron was artificially removed or somehow altered, what affect would you expect to occur? A. The 5' end of the intron would not recognize where to bind to create the lariat and the intron would not be removed properly. B. The 3' end of the intron would not recognize where to bind to create the lariat and the intron would not be removed properly. C. The 5' end of the mRNA would not know where to bind to the ribosomal subunit. D. Exons would be removed instead of introns when making the final mRNA transcript.
A. The 5' end of the intron would not recognize where to bind to create the lariat and the intron would not be removed properly.
The graph below is demonstrating the allele frequency of a dominant allele (B) at one genetic locus in 3 populations over 50 generations. Population A and C (the top and bottom lines respectively) have 10 individuals (N = 10) and Population B (middle line) has 1000 (N = 1000). In this population, there are only 2 alleles (B, b). Using this graph and its data, which one of the following statements is accurate? http://s32.postimg.org/4hfc8or1h/question9.png A. This graph is demonstrating the effect of small population size on genetic variability due to genetic drift. B. This graph is demonstrating the effect of mutations on genetic variability. C. This graph is demonstrating the effect of natural selection on genetic variability. D. This graph is demonstrating the effect of small population size on genetic variability due to gene flow.
A. This graph is demonstrating the effect of small population size on genetic variability due to genetic drift.
A mother has Type A blood while the father has Type B blood. What are the possible blood types of their children? A. Type AB, Type A, Type B and Type O B. Type AB, Type A and Type B only C. Type A and Type B only D. Type AB only
A. Type AB, Type A, Type B and Type O
If a mother has Type AB blood and her partner has Type B blood, which of the following blood types could their children NOT have? (Assume the Bombay phenotype is NOT occurring here.) A. Tpye O B. Type A C. Type B D. Type AB
A. Type O
Which of the following was a contribution Rosalind Franklin made to the understanding of DNA? A. Used X-ray diffraction to show that the structure of DNA is helical B. Determined that DNA contains four different nitrogenous bases C. Found that "the transforming principle" is destroyed by enzymes that hydrolyze DNA D. Found that the phosphorus containing components are the genetic material of phages E. Discovered "the transforming principle" that could genetically alter bacteria
A. Used X-ray diffraction to show that the structure of DNA is helical
Consider the following pedigree. The filled in shapes indicate an individual who expresses the phenotype. Choose the MOST LIKELY mode of inheritance for the trait. Assume this is a relatively rare allele and that individuals marrying into the family are most likely not carriers. http://s32.postimg.org/sb435pqcl/Question5.png A. X-linked recessive B. autosomal recessive C. autosomal dominant D. Y-linked E. X-linked dominant
A. X-linked recessive
Duchenne's Muscular Dystrophy (DMD) is an X-linked recessive disease that results in a deterioration of muscles and eventual death. Individuals with DMD are almost always male but very rarely there are females who have the disease. What would be possible genotypes of the parents of a female with DMD? Assume "D" is the normal allele and "d" is the DMD allele. A. XDXd x XdY B. XDXD x XDY C. XDXd x XDY D. XdXd x XDY
A. XDXd x XdY
Hemophilia is a recessive X-linked genetic disease. A father who has hemophilia will give the defective allele to ___________ A. all of his daughters and none of his sons. B. all of his daughters and 1/2 of his sons. C. none of his daughters and all of his sons. D. 1/2 of his daughters and none of his sons.
A. all of his daughters and none of his sons.
Alternative processing of eukaryotic mRNA, leading to distinct products from a single section of DNA, can include all of the following EXCEPT: A. alternative start transcription sites. B. alternative cleavage and poly-adenylation sites. C. alternative splicing. D. All of these can take place.
A. alternative start transcription sites.
You would suspect a disease is inherited in the _______________ manner if you see males and females equally affected and if when there are 2 unaffected parents who are closely related (inbreeding!), 3/4 of the time they would have an unaffected child. A. autosomal recessive B. autosomal dominant C. X-linked recessive D. X-linked dominant
A. autosomal recessive
In labrador retrievers, there are two genes that are responsible for the coat color which can be black, brown or yellow. One gene has two versions, a dominant black allele and a recessive brown allele. The second gene is recessively epistatic to the black/brown gene and creates the yellow coat color regardless of the first gene's genotype. A dog with the genotype of BbEe would have what coat color? A. black B. brown C. yellow
A. black
A(n) _________ is a term given to someone who is a heterozygote for a recessive trait. A. carrier B. true breeder C. proband D. chromatin
A. carrier
Which of the following stages of translation does NOT depend on base pairing? A. charging of tRNA molecules B. initiation C. elongation D. both initiation and elongation E. both initiation and charging of tRNA molecules
A. charging of tRNA molecules
Match the stages of mitosis to the description of what is occurring that stage Metaphase A. chromosomes are arranged at the middle of the cell B. nuclear envelope reforms around each set of daughter chromosomes C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite chromosomes D. sister chromatids separate at the centromere and move towards opposite poles of the cell E. chromosomes initially condense and centrosomes begin to move apart
A. chromosomes are arranged at the middle of the cell
Linked genes do not segregate together 100% of the time due to the event of _____________. A. crossing over B. repulsion C. independent assortment D. mutations E. coupling
A. crossing over
The full name of the next nucleotide (before it actually joins) that is joining the growing strand of DNA during replication is ___________. A. deoxyribonucleoside triphosphate B. deoxyribonucleoside monophosphate C. deoxyribonucleotide triphosphate D. deoxyribonucleotide monophosphate
A. deoxyribonucleoside triphosphate
The study of heritable changes caused by the activation and deactivation of genes without any change in DNA sequence is called: A. epigenetics B. genetic drift C. Mendelian genetics D. population genetics
A. epigenetics
In species such as birds that use the ZZ/ZW sex determination system, the ______ are the heterogametic sex and have ____ for their sex chromosomes. A. females/ZW B. females/ZZ C. males/ZW D. males/ZZ
A. females/ZW
There are 2 alleles for coat color in a species of hamster, B = black and b = dark brown. Two parental hamsters, BB and bb were mated to produce a F1 generation that are all uniformly tan. The F1 offspring were allowed to mate to produce F2 offspring. In the F2 offspring, the phenotypic and genotypic ratios were both 1:2:1. What type of dominance is occurring? A. incomplete dominance B. co-dominance C. complete dominance
A. incomplete dominance
A genetic cross between two individuals reveals a phenotypic ratio of 9:3:3:1 in the offspring. A possible explanation for this ratio is that there are two genes with two possible alleles that exhibit: A. independent assortment B. linkage C. recessive epistasis D. dominant epistasis
A. independent assortment
What is the function of allolactose in regulation of the lac operon? A. inducer B. repressor C. activator D. promoter E. regulatory protein
A. inducer
Okasaki fragments are present on the _______ strand of the newly synthesized DNA. A. lagging B. leading C. both leading and lagging
A. lagging
You are shown an unknown cell under a microscope. Which of the following structures or molecule would allow you to identify it as a eukaryotic cell? A. nucleus B. DNA C. cell membrane D. ribosomes
A. nucleus
The tRNA carrying N-formylmethionine will match with its codon at the ________ site of the ribosome. A. peptidyl (P) B. aminoacyl (A) C. exit (E) D. Shine-Dalgarno
A. peptidyl (P)
The amino acid sequence of a polypeptide is referred to as the ______ sequence of the polypeptide. A. primary B. secondary C. tertiary D. initial
A. primary
What parts of DNA make up a typical bacterial transcription unit (in the correct order that they occur, 5'--3')? A. promoter, transcriptional start site, RNA coding region terminator B. transcriptional start site, RNA coding region, promoter, terminator C. promoter, transcriptional start site, terminator, RNA coding region D. enhancer, basal promoter, transcriptional start site, terminator
A. promoter, transcriptional start site, RNA coding region terminator
Which of the following does not occur during post-transcriptional processing of RNA in eukaryotes? A. removal of exons B. removal of introns C. addition of a poly-A tail at the 3/ end D. addition of a 7-methyl guanosine cap at the 5' end
A. removal of exons
An operon that is normally ON is referred to as a/an ________operon. A. repressible B. inducible C. enhanced D. promotable
A. repressible
In Mendel's original monohybrid crosses with pea plants, he discovered that for the pea seed color, yellow was the dominant trait over green seeds and round was the dominant trait over wrinkled seeds. In a dihybrid cross of a plant that had wrinkled, yellow seeds with one that had round, yellow seeds, the following offspring phenotype ratios were found. Assuming the genes for seed color and seed shape independently assort, what were the genotypes of the parents? (Note: This is NOT a classic F1 mating that is producing F2 offspring.) Offspring Phenotypes: 6 wrinkled, yellow 2 wrinkled, green 6 round, yellow 2 round, green A. rrYy x RrYy B. rrYy x RRYy C. rrYY x RrYy D. rrYy x RrYY
A. rrYy x RrYy
When an autosomal gene has zero penetrance in females, this gene is considered ____________. A. sex limited B. sex influenced C. X-linked D. Y-linked
A. sex limited
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Prophase II A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
A. spindle fibers form inside haploid cells
Translation of a bacterial mRNA requires these types of RNA: _____________. A. tRNA and rRNA B. rRNA and snRNA C. tRNA and snRNA D. rRNA, tRNA, and snRNA
A. tRNA and rRNA
DNA polymerase adds new nucleotides to _____ of the growing new daughter strand. A. the 3' end B. the 5' end C. either end
A. the 3' end
Rho dependent termination of bacterial transcription involves ______________. A. the Rut site B. inverted repeats that are transcribed into the RNA C. a string of A's on the template strand that are transcribed into U's D. the Rat1 protein E. multiple cleavage sites to release the mRNA transcript
A. the Rut site
The ends of eukaryotic DNA become progressively shorter with each round of DNA replication because _____________. A. the lagging strands do not have a free 3' end to complete the DNA replication B. the RNA primers can not be removed from the lagging strands. C. the leading strands do not have a free 3' end to complete the DNA replication D. the circular nature of eukaryotic DNA does not have a free 3' end to complete the DNA replication
A. the lagging strands do not have a free 3' end to complete the DNA replication
The genetic code is said to be "degenerate" or "redundant" because ____________. A. there are more possible codons than amino acids B. there are more amino acids than possible codons C. some codons can specify more than one amino acid D. there are more tRNAs than amino acids
A. there are more possible codons than amino acids
Assume there are 3 linked genes in Drosophila. One gene has a mutation for cut wings (ct), one has a mutation for black body (b) and the third has a mutation for vermillion eyes (v). After conducting a test cross involving these 3 genes, a researcher determines that the vermillion eyes gene is in the middle. The heterozygote used for this test cross has its alleles in the coupling configuration. Based on this information, what would be the expected phenotypes of the offspring resulting from a single cross over event between the cut wings gene and the vermillion eyes gene? A. vermillion eyes/black bodies offspring or cut wings offspring B. cut wings/vermillion eyes/black body offspring or all wild type offspring C. vermillion eyes offspring or all wild type offspring D. cut wing offspring or all wild type offspring E. cut wings/vermillion eyes/black body offspring or black body offspring
A. vermillion eyes/black bodies offspring or cut wings offspring
Considering both induction by allolactose and catabolite repression, mRNA is produced in quantity from the lac operon only: A. when lactose is present and glucose is absent. B. when lactose is present and glucose is present. C. when lactose is absent and glucose is present. D. when lactose is absent and glucose is absent.
A. when lactose is present and glucose is absent.
For 2 genes that follow independent assortment, an individual who is homozygous dominant for gene A but a heterozygote for gene B could produce which of the following gametes for these genes? A. Only AB B. AB or Ab C. Only Ab D. AABb
AB or Ab
Consider three independently assorting genes, A/a, B/b, and C/c. What is the probability of obtaining a triply recessive individual from parents that are AaBbCC and AABbCc? A. 25% B. 0% C. 75% D. 100% E. 50%
B. 0%
There are 3 possible alleles A (p), B (q) and C (r) at a gene loci in a population. Don't worry about dominance. The following genotype frequencies are found in a population of 100 people: AA: 15%; AB: 10%; AC: 12%; BB: 22%; BC: 30%; CC: 11% What is the frequency of the C allele (r) in this population? A. 0.53 B. 0.32 C. 0.27 D. 0.64
B. 0.32
If there are two alleles (A and a) at a genetic locus in a population and the population is at Hardy-Weinberg equilibrium, which frequency of "A" would produce the greatest frequency of heterozygotes? A. 1 B. 0.5 C. 0.1 D. 0.25
B. 0.5
In a certain population with two alleles, there are 58 homozygous dominant individuals, 72 heterozygotes and 20 homozygous recessive. What is the frequency of p in this population? A. 0.43 B. 0.63 C. 0.37 D. 0.87 E. 1.25
B. 0.63
For two alleles of the same gene that demonstrate incomplete dominance, you would expect to see a __________ phenotypic ratio in the F2 generation offspring. A. 3:1 B. 1:2:1 C. 9:3:3:1 D. 1:2
B. 1:2:1
If an anti-codon has this sequence: 3' A G U 5' What is the sequence of the DNA that would provide the template for the mRNA for this anti-codon? A. 5' T C A 3' B. 3' A G T 5' C. 5' U C A 3' D. 5' A G T 3'
B. 3' A G T 5'
In a species of snails, there are 2 genes on the same chromosome. One gene gives the snail a striped shell (S) and is dominant over the allele which is non-striped (s). The other gene has a dominant allele for black shells (B) and a recessive allele for brown shells (b). In a cross of snail that is heterozygous for both genes with a non-striped, brown snail, the following offspring numbers were found: striped/black: 80 non-striped/brown: 78 striped/brown: 37 non-striped/black: 41 How far apart in map units are the 2 genes? A. 25 mu B. 33 mu C. 50 mu D. 62 mu E. 57 mu
B. 33 mu
Two genes in Drosophila code for body color and eye color. The wild type body trait is gray (b+) and the mutant version is black (b). The wild type eye color is red (p+) and the mutant version is purple. These genes are right next to each other on the same chromosome and for the sake of this question, let's assume they never cross over. If you test cross a heterozygote for both genes (p+p/b+b) with a homozygous mutant for both genes (pp/bb), what is the expected ratio of offspring? A. 50% gray body/purple eyes and 50% black body/red eyes B. 50% gray body/red eyes and 50% black body/purple eyes C. All gray body/red eyes D. All black body/purple eyes
B. 50% gray body/red eyes and 50% black body/purple eyes
A female tortoiseshell cat is mated with a male black cat. Predict the possible phenotypes (orange, black or tortoiseshell), including sex, of their litter. A. All females will be black and all males will be orange. B. 50% of the females will be black and 50% will be tortoiseshell and 50% of the males will be orange and 50% of the males will be black. C. 50% of the females will be black and 50% will be orange and all males will be orange. D. 50% of the females will be black and 50% will be orange and 50% of the males will be orange and 50% of the males will be black. E. All females will be orange and all males will be black.
B. 50% of the females will be black and 50% will be tortoiseshell and 50% of the males will be orange and 50% of the males will be black.
In a species of melons, there is a dominantly epistatic gene "E" that interacts with a hypostatic gene that has two alleles, the dominant "P" allele for purple color and recessive "p" for green color. The epistatic gene will cause white melons regardless of the hypostatic genotype. If a heterozygote for both genes is mated with a homozygous dominant for the hypostatic gene who is heterozygous for the epistatic gene, what would be the expected phenotypic ratios from this mating? A. 2/8 would be white and 6/8 will be purple B. 6/8 would be white and 2/8 will be purple C. All will be white D. All will be purple
B. 6/8 would be white and 2/8 will be purple
Albinism is an autosomal recessive disorder that causes lack of pigmentation. Two parents with normal pigmentation have an albino child. What is the chance they will have a child with normal pigmentation? A. 50% B. 75% C. 100% D. 0% E. 25%
B. 75%
A species with a 2n=16 has only autosomes. This species would have ______ linkage groups A. 4 B. 8 C. 16 D. 32 E. It would depend on the sex.
B. 8
Assuming a typical dihybrid cross in which one allele is completely dominant to the other, what phenotypic ratio is expected if the F1's are self-crossed? A. 3:1 B. 9:3:3:1 C. 1:3 D. 1:1:1:1
B. 9:3:3:1
What is the Pribnow box? A. A consensus sequence found at -10 on the template strand in a bacterial promoter. B. A consensus sequence found at -10 on the non-template strand in a bacterial promoter. C. A consensus sequence found at -10 in the RNA coding region of a gene. D. A consensus sequence found at -10 in the terminator region of a gene.
B. A consensus sequence found at -10 on the non-template strand in a bacterial promoter.
If a parent has the genotype AABbCc, what possible gametes could they have? Assume the 3 genes independently assort. A. Only Abc or ABc B. ABC, AbC, Abc or ABc C. Only ABC or ABc D. Only ABC
B. ABC, AbC, Abc or ABc
Which of the following is an example of an epigenetic change? A. Loss of the bonds between base pairs B. Addition of methyl groups to cytosines of a gene to alter gene expression C. Substitution of several base pairs to alter the nucleotide sequence for a gene D. Deletion that removes two whole genes from the genome E. Change in the consensus sequences of promoter regions
B. Addition of methyl groups to cytosines of a gene to alter gene expression
Short index fingers is a sex-lnfluenced traits in humans. It is a dominant trait in males and a recessive trait in females. What would be the expected phenotype of a male offspring of a cross between a heterozygous short-fingered man with a short-fingered woman? A. All long-fingered males B. All short-fingered males C. 1/2 long-fingered males and 1/2 short-fingered males D. 3/4 short-fingered males and 1/4 long-fingered males
B. All short-fingered males
In the diagram below, which letter indicates the 3′ end of the lagging strand? http://s32.postimg.org/7wl4r209x/Question11.png A. A B. B C. C D. D E. A and B
B. B
Julie goes to a labrador retriever breeder to buy a lab puppy. Julie really wants a yellow lab but the breeder has only black labs in her breeding program. The breeder assures Julie that it will be possible to get a yellow lab puppy from a breeding between her two black labs. If the breeder is correct, what are possible genotypes for the black lab parents? Assume B = black allele; b = brown allele; E = dominant epistatic allele; e = recessive epistatic allele A. BBEE x BBEE B. BBEe x BbEe C. BbEE x BbEE D. BbEE x BbEe
B. BBEe x BbEe
Which of the following is NOT true of bacterial DNA? A. Most bacterial genomes consist of a single circular DNA molecule. B. Bacterial DNA is attached to histones that help to compact it. C. Bacterial DNA is confined to a region in the cell called the nucleoid. D. Many bacteria contain additional DNA in the form of small circular molecules called plasmids.
B. Bacterial DNA is attached to histones that help to compact it.
Which of the following is FALSE of bacterial DNA? A. Most bacterial genomes consist of a single circular DNA molecule. B. Bacterial DNA is not attached to ANY proteins that help to compact it. C. Bacterial DNA is confined to a region in the cell called the nucleoid. D. Many bacteria contain additional DNA in the form of small circular molecules called plasmids. E. Bacterial DNA is double stranded just like eukaryotic DNA.
B. Bacterial DNA is not attached to ANY proteins that help to compact it.
An organism has a mutation in the gene that codes for separase so that no functional separase can be made by this individual. What consequence would occur from this mutation? A. During meiosis, sister chromatids would never separate because cohesin could not be broken down but homologous chromosomes would separate. B. Both sister chromatids and homologous chromosomes would never separate because cohesin could not be broken down. C. During meiosis, homologous chromosomes would never separate during meiosis but sister chromatids would separate. D. Sister chromatids would separate prematurely during mitosis.
B. Both sister chromatids and homologous chromosomes would never separate because cohesin could not be broken down.
When this molecule is synthesized, both strands of a DNA molecule are used as a template. A. Both RNA and DNA B. DNA only C. Neither RNA or DNA D. RNA onyl
B. DNA only
Which of the following statements is NOT correct about the process of transcription? A. Transcription of a given gene takes place on only one of the two DNA strands. B. During transcription, the RNA molecule is synthesized in the 3' to 5' direction. C. During transcription, the RNA molecule that is synthesized is anti-parallel and complementary to the template DNA strand. D. The start site and direction of transcription are determined by a region of the DNA strand known as the promoter. E. The RNA molecule that is synthesized will have U in place of T.
B. During transcription, the RNA molecule is synthesized in the 3' to 5' direction.
True or False: A normal female chicken can be homozygous for a Z-linked gene. Hint: Compare the female chicken's sexual genotype to mammals. A. True B. False
B. False
True or False: Because there are 64 possible unique triplets and only 20 amino acids, a codon can code for more than one amino acid. A. True B. False
B. False
True or false: You can always tell the genotype of an individual who displays the dominant phenotype. A. True B. False
B. False
Match the correct human sex chromosome aneuploidy with the correct statement. Y0 A. Sterile male with feminine characteristics B. Fatal C. Only known human viable monosomy D. Phenotypically fertile females E. Phenotypically fertile male
B. Fatal
Which of the following statements about gene regulation concerning operons is FALSE? A. Negative inducible operons occur typically in catabolic pathways where precursor molecules need to be broken down into other substances. B. For an operon under negative repressible control, a small molecule called an inducer is required to prevent the gene's repressor from binding to DNA. C. For a operon under positive repressible control, the normal state is transcription of the genes, stimulated by an activator. D. A regulator gene has its own promoter and is transcribed into an independent mRNA.
B. For an operon under negative repressible control, a small molecule called an inducer is required to prevent the gene's repressor from binding to DNA.
Negatively supercoiled DNA has which of the following properties? A. It allows less transcription but allows more DNA to fit in a smaller space. B. It allows more transcription and also allows more DNA to fit in a smaller space. C. It allows more transcription but does not allow DNA to fit in a smaller space. D. It allows less transcription and allows less DNA to fit in a smaller space.
B. It allows more transcription and also allows more DNA to fit in a smaller space.
How does histone acetylation affect chromatin? A. It loosens the chromatin and allows increased transcription by making the histones more positive. B. It loosens the chromatin and allows increased transcription by making the histones less positive. C. It helps the histones have a greater attraction to DNA. D. It inhibits DNA replication by making it more difficult to separate the DNA strands.
B. It loosens the chromatin and allows increased transcription by making the histones less positive.
During DNA replication, DNA polymerase has which of the following limitations? A. It requires the use of primers and it can only synthesize DNA from one strand of template DNA. B. It requires the use of primers and it can only synthesize DNA in the 5' to 3' direction. C. It requires the use of RNA polymerase and it can only synthesize DNA in the 5' to 3' direction. D. It requires the use of primers and it can only synthesize DNA in the 3' to 5' direction.
B. It requires the use of primers and it can only synthesize DNA in the 5' to 3' direction.
Consider this diagram: Both a "green" mRNA and a "purple" mRNA can be transcribed from these DNA strands. One has the upper strand as its template strand and the other has the lower strand as its template. Which DNA strand (lower or upper) is the template strand for the GREEN gene? http://s32.postimg.org/d5fykboyt/question7.jpg A. Upper B. Lower C. Both can be the template strand for the green gene.
B. Lower
If there an abundance of glucose in the environment, the lac operon will be turned ON or OFF? A. ON B. OFF
B. OFF
Following a monohybrid P cross of two contrasting true breeders, what are the possible genotypes in the F1 offspring? (Using "A" to represent the dominant allele and "a" to represent the recessive allele) A. Only AA or aa B. Only Aa C. Only aa D. Only AA E. AA, Aa, or aa
B. Only Aa
Splicing requires all of the following EXCEPT: A. specific sequences at the 5' and 3' ends of introns. B. RNA polymerases that recognize the splicing sequences. C. two cleavages, excising the introns. D. ligation of the exons.
B. RNA polymerases that recognize the splicing sequences.
The nucleotide below is a/an _____________. http://s32.postimg.org/czz15vbol/Question10.png A. RNA purine B. RNA pyrimidine C. DNA purine D. DNA pyrimidine E. You can not tell from this structural formula
B. RNA pyrimidine
A ribozyme is a molecule that is classified as ___________ but serves the role of a/an __________molecule because it can catalyze chemical reactions. A. DNA; enzyme B. RNA; enzyme C. A protein; RNA D. an enzyme; DNA E. RNA; carbohydrate
B. RNA; enzyme
Which one of the following statements is TRUE about recombination? A. Recombination occurs between two of the sister chromatids of a homologous pair. B. Recombination occurs between two of the non-sister chromatids of a homologous pair. C. Recombination occurs between all four of the non-sister chromatids of a homologous pair. D. Recombination occurs between all four of the sister chromatids of a homologous pair.
B. Recombination occurs between two of the non-sister chromatids of a homologous pair.
If an operon is under positive inducible control, what would be the result of a mutation that eliminates the activator protein? A. The transcription of the structural genes will not be affected since an activator is not required for this type of operon. B. Since transcription will require an activator protein, transcription of the structural genes will be turned off. C. The operon will need to use a repressor protein instead to control the transcription of the structural genes. D. The structural genes' transcription will turn on permanently, producing constant mRNAs.
B. Since transcription will require an activator protein, transcription of the structural genes will be turned off.
Which of the following is a sequence of DNA which signals the initiation of eukaryotic transcription? A. sigma factor B. TATA box C. Pribnow box D. TFIID
B. TATA box
Which of the following statements distinguishes bacterial mRNA transcripts from eukaryotic mRNA transcripts? A. The 5' cap sequence is responsible for recognizing and binding to the small ribosomal subunit in bacteria but not eukaryotes. B. The Shine-Dalgarno sequence is responsible for recognizing and binding to the small ribosomal subunit in bacteria but not eukaryotes. C. Transcription and translation take place at the same time in eukaryotic cells but are separated typically in bacteria. D. Bacterial transcripts must be edited because they contain large numbers of introns. E. The 5′ end and 3′ end of mRNA transcripts are modified in bacteria but not eukaryotes.
B. The Shine-Dalgarno sequence is responsible for recognizing and binding to the small ribosomal subunit in bacteria but not eukaryotes.
What is wobble? A. The effect that occurs when the 2 subunits of the ribosome join together imprecisely. B. The breakdown of base pair rules that allow anti-codons to pair with codons that are not completely complementary. C. The existence of modified nucleotides in tRNA which creates mismatches in amino acid attachment. D. The phenomenon that occurs when a codon is made of the same nucleotides (e.g. UUU or AAA).
B. The breakdown of base pair rules that allow anti-codons to pair with codons that are not completely complementary.
The tortoiseshell coat pattern of cats is caused by X-inactivation of an X-linked gene that has two alleles, an orange version and a black version. What would be the expected genotypes of the parents of a litter of kittens in which there were 2 tortoiseshell females, 1 black female, 2 orange males and 1 black male. (Note: Don't worry about the exact ratios, just focus on what genotypes the parents must have to produce any number of these offspring phenotypes.) A. The mom is a tortoiseshell and the father is orange. B. The mom is a tortoiseshell and the father is black. C. The mom is black and the father is orange. D. The mom is orange and the father is black.
B. The mom is a tortoiseshell and the father is black.
What would happen to the lac operon in the absence of allolactose? A. The structural genes within the lac operon will be transcribed all the time. B. The repressor regulator protein will bind to the operator and prevent the transcription of the structural genes. C. The catabolite activator protein becomes inactivated and no transcription occurs. D. The cAMP levels will rise in the absence of allolactose, which in turn inactivates transcription of the structural genes.
B. The repressor regulator protein will bind to the operator and prevent the transcription of the structural genes.
Consider this scenario: Several structural genes code for the enzymes involved in manufacturing Substance X in bacteria. When enough Substance X is made, the operon turns off. Which of the following statements would be true in this situation? A. This operon is negatively repressible and Substance X is the repressor molecule. B. This operon is negatively repressible and Substance X is the corepressor molecule. C. This operon is negatively inducible and Substance X is the repressor molecule. D. This operon is negatively inducible and Substance X is the corepressor molecule.
B. This operon is negatively repressible and Substance X is the corepressor molecule.
Tall (T) is a dominant trait in corn plants over dwarf (t). A tall plant is test-crossed, and half of the offspring produced are tall and half are dwarf. What are the genotypes of the individuals that were crossed if the mating followed exactly what was predicted? A. TT x tt B. Tt x tt C. Tt x Tt D. TT x tt
B. Tt x tt
In your genetics lab, you are given 4 tubes of different samples of nucleic acids BUT you do not know which sample is what type of nucleic acid. The possible samples are: human DNA, human mRNA, single stranded DNA from a parvovirus and double stranded RNA from a rotavirus. During your lab, you are able to analyze each sample for the nucleotide percentages. Your results are in the table below. Given this information, which sample tube most likely contains the human mRNA? Tube: A, C, U, T, G 1: 32, 19, 0, 32, 19 2: 34, 16, 15, 0, 35 3: 30, 21, 0, 26, 23 4: 33, 16, 34, 0, 17 A. Tube 1 B. Tube 2 C. Tube 3 D. Tube 4
B. Tube 2
The following pedigree shows the inheritance of an X-linked recessive trait. What is the genotype of individual II-2? Assume "+" is the normal, dominant allele and "a" is the recessive allele. http://s32.postimg.org/76v2xttnp/Picture9.png A. X+X+ B. X+Xa C. XaXa D. You can not tell without more information about this family.
B. X+Xa
Testcross: Aa Bb Cc x aa bb cc ABC 580 abc 592 ABc 45 abC 40 AbC 89 aBc 94 aBC 3 Abc 5 Total: 1448 Which offspring are the double recombinant? A. ABc and abC B. aBC and Abc C. ABC and abc D. AbC and aBc
B. aBC and Abc
During the ___________ stage of _____________, sister chromatids of haploid cells are separated. A. anaphase I/meiosis I B. anaphase II/meiosis II C. anaphase/mitosis D. telophase I/meiosis I
B. anaphase II/meiosis II
Consider the following pedigree. The filled in shapes indicate an individual who expresses the phenotype. Choose the MOST LIKELY mode of inheritance for the trait. Assume this is a relatively rare allele and that individuals marrying into the family are most likely not carriers. http://s32.postimg.org/kvzjyg90l/Question4.png A. X-linked dominant B. autosomal dominant C. Y-linked D. autosomal recessive E. X-linked recessive
B. autosomal dominant
In a classic Mendelian monohybrid mating, a researcher mated one of the F1 offspring with a parental homozygous recessive parent. This type of mating is called a ___________ and you would expect to find a ___________ for the genotypic ratio in the offspring. A. test cross/1:1 (Aa:aa) B. back cross/1:1 (Aa:aa) C. reciprocal cross/1:1 (Aa:aa) D. back cross/1:1 (AA:Aa)
B. back cross/1:1 (Aa:aa)
Recombination occurs through __________ A. crossing over between sister chromatids and independent assortment. B. crossing over between non-sister chromatids of the same homologous pair and independent assortment. C. crossing over between non-sister chromatids of the same homologous pair only. D. independent assortment only. E. crossing over between sister chromatids only.
B. crossing over between non-sister chromatids of the same homologous pair and independent assortment.
A new virus has been discovered in a species of bacteria that inhabit hot springs. The viral genome is found to consist of four nucleotides in the following ratios: 8% A, 42% C, 42% G, and 8% U. The genome must be made of: A. double-stranded DNA. B. double-stranded RNA. C. single-stranded DNA. D. single-stranded RNA.
B. double-stranded RNA.
For the Hardy-Weinberg equation, which one of these does NOT represent the correct frequency of alleles or genotypes for a gene that has 2 alleles (A, a)? A. f (aa) = q x q (i.e. q squared) B. f (AA) = p C. f (A) = p D. f (a) = q E. f (Aa) = 2pq
B. f (AA) = p
In the insect sex determination system, the _______ are considered the homogametic sex because they have 2 X chromosomes. A. males B. females
B. females
The ______ is all of the genetic information for all loci within a breeding population. A. genotype B. gene pool C. genome D. gene E. generation
B. gene pool
Normal human males can be ____________ for alleles on the X chromosome. A. heterozygous B. hemizygous C. homozygous dominant D. homozygous recessive
B. hemizygous
A researcher is investigating the inheritance pattern for some varieties of roses. He knows the flower color is controlled by just one gene and there are only 2 alleles possible for that gene. When he breeds 2 two lavender roses, he ends up with some offspring that have lavender flowers like the parents, some have all white flowers and some have all deep purple flowers. Based on this information, the researcher suspects the inheritance pattern is __________ for color in these roses. A. complete dominance B. incomplete dominance C. co-dominance D. multiple alleles
B. incomplete dominance
Operons that work in catabolic pathways are typically: A. repressible B. inducible
B. inducible
Heterochromatin is characterized by all of the following EXCEPT: A. it is present all over the inactive X chromosomes in female mammals. B. it contains genes that are transcribed at high levels. C. it remains highly condensed. D. it is present at centromeres and telomeres.
B. it contains genes that are transcribed at high levels.
A human with sex chromosomes XXY would like appear to be: A. female B. male
B. male
The only way for adaptive evolution to take place is if there is ___________ within a population. A. random mating B. natural selection C. genetic drift D. gene flow E. Hardy-Weinberg equilibrium
B. natural selection
Recombinant chromosomes are created during crossing over events between ____________ A. non-sister chromatids of the same homologous pair during mitosis. B. non-sister chromatids of the same homologous pair during meiosis. C. During meiosis, homologous chromosomes would never separate during meiosis but sister chromatids would separate. D. Sister chromatids would separate prematurely during mitosis.
B. non-sister chromatids of the same homologous pair during meiosis.
Match the stages of mitosis to the description of what is occurring that stage Telophase A. chromosomes are arranged at the middle of the cell B. nuclear envelope reforms around each set of daughter chromosomes C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite chromosomes D. sister chromatids separate at the centromere and move towards opposite poles of the cell E. chromosomes initially condense and centrosomes begin to move apart
B. nuclear envelope reforms around each set of daughter chromosomes
Imagine in Meselson and Stahl's experiment on modes of DNA replication, they found 2 distinct bands (one "light" and one "heavy") after one round of replication. This result would have suggested ___________ mode(s) of DNA replication. A. only the semi-conservative B. only the conservative C. only the dispersive D. both semi-conservative and dispersive E. only conservative and semi-conservative F. all 3
B. only the conservative
Which of the following is NOT necessary for RNA polymerase to recognize the promoter of a bacterial gene? A. sigma factor B. origin of replication C. -10 consensus sequence D. -35 consensus sequence
B. origin or replication
The mutated breast cancer gene BRCA 1 is inherited in an autosomal dominant manner yet only approximately 80% of women who inherit the defective allele will develop breast cancer during their lifetime. Researchers therefore often describe the BRCA 1 gene as having incomplete ___________. A. expressivity B. penetrance C. epistasis D. dominance
B. penetrance
Which of the following could be an RNA nucleotide but not a DNA nucleotide? A. phosphate, deoxyribose, thymine B. phosphate, ribose, uracil C. phosphate, deoxyribose, uracil D. phosphate, deoxyribose, adenine E. phosphate, ribose, thymine
B. phosphate, ribose, uracil
An operon that is normally transcribed with the assistance of an activator, but can be turned off under certain conditions is known as: A. positive inducible. B. positive repressible. C. negative inducible. D. negative repressible.
B. positive repressible.
Crossing over occurs during what stage in cell division? A. prophase of mitosis B. prophase I of meiosis C. prophase II of meiosis D. metaphase I of meiosis
B. prophase I of meiosis
In negative operon control (both repressible and inducible), the regulatory protein is a/an _________. A. activator B. repressor C. inducer D. enhancer E. promoter F. terminator
B. repressor
The________ is a type of regulator protein that binds to a region of DNA in the promoter of a gene called the operator and prevents transcription from taking place. A. inducer B. repressor C. activator D. terminator
B. repressor
For the same genes in #4, assume crossing over does occur. When you test cross a heterozygote for both genes with a homozygous mutant for both genes, you obtain the following progeny: gray/purple: 48 gray/red: 11 black/purple: 13 black/red: 51 For the heterozygote, are these genes in coupling (cis) or repulsion (trans) configuration? A. coupling (cis) B. repulsion (trans)
B. repulsion (trans)
If the hydrogen bonds between complementary base pairs were disrupted, which level of organization in DNA would be immediately affected? A. primary B. secondary C. tertiary D. None of the levels would be affected.
B. secondary
Meselson and Stahl showed that DNA is replicated by a __________. A. conservative model B. semi-conservative model C. dispersive model D. semi-dispersive model E. conservative model in prokaryotes and semi-conservative model in eukaryotes
B. semi-conservative model
Consider 3 genes on the same chromosome in fruit flies with the mutant phenotypes of purple eyes, bent wings and short legs. In a trihybrid cross, a fly who is heterozygous for all three genes is testcrossed and the following offspring are produced. All mutant traits are recessive to their wildtype alternative. purple eyes-6 purple eyes, bent wings-137 purple eyes, short legs, bent wings-291 short legs-142 short legs, bent wings-3 bent wings-30 purple eyes, short legs-34 wildtype for all 3-339 What is the order of the genes on the chromosome? A. purple eyes, short legs, bent wings B. short legs, purple eyes, bent wings C. short legs, bent wings, purple eyes D. bent wings, short legs, purple eyes
B. short legs, purple eyes, bent wings
The spliceosome structure is a large complex which consists of ________________. A. snRNAs, rRNAs, mRNAs, tRNAs and assorted proteins B. snRNAs and assorted proteins C. snRNA, rRNAs and assorted proteins D. mRNAs and assorted proteins
B. snRNAs and assorted proteins
During initiation of translation, ________. A. the tRNA carrying methionine binds to the A site of the small ribosomal subunit B. specific rRNA base pairs with a sequence in mRNA to position a ribosome at the start codon C. IF-3 must be recruited to the 70S ribosome in order for the ribosome complex to assemble D. no energy is needed because simple base pair rules allow complementary base pairing E. the 30S and 70S ribosome subunits join together first for proper binding of an mRNA
B. specific rRNA base pairs with a sequence in mRNA to position a ribosome at the start codon
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Telophase II A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
B. spindle fibers break down in haploid cells without duplicated
What's the name of the protective region at the end of linear chromosomes that contains non-coding regions of DNA? A. centromeres B. telomeres C. centrosomes D. chromatids E. telophase
B. telomeres
Okazaki fragments are associated with synthesis of: A. the leading strand. B. the lagging strand. C. both the leading and the lagging strands. D. single-stranded circular DNA.
B. the lagging strand.
The next amino acid added to the growing polypeptide chain will be: Note: The diagram incorrectly has Gly (glycine) as the amino acid that matches to the "CCC" codon on the mRNA. It should be Pro (proline). This mistake however does not affect the answer of the question being asked which is what NEXT amino acid will join the chain.) http://s32.postimg.org/mwjcrs89x/Question8.png A. serine (Ser) B. threonine (Thr) C. alanine (Ala) D. glycine (Gly) E. a release factor
B. threonine (Thr)
The non-recombinant gametes from a 3 point test cross are ACB and acb. The double cross over gametes are ACb and acB. Which gene is in the middle based on these results? A. A B. B C. C
B.B
Consider the following three-point cross: http://s32.postimg.org/rav7bpv1h/Screen_Shot_2016_05_03_at_5_09_52_PM.png
C.
At a certain genetic loci, there are only 3 alleles in a given population. The frequencies of the 3 alleles are represented by p, q and r. If 36% of this population is homozygous for p and 4% homozygous for q, what is the frequency of r in this population? A. 0.36 B. 0.04 C. 0.2 D. 0.44 E. 0.56
C. 0.2
For an X-linked gene, there are two alleles, A and a. In a certain population, there are 25 homozygous dominant females, 10 heterozygous females, no homozygous recessive females and 30 males with the recessive allele and 20 males with the dominant allele. What is the frequency of the recessive allele (q) in this population? A. 0.45 B. 0.27 C. 0.33 D. 0.5
C. 0.33
Consider two independently assorting genes which demonstrate complete dominance for 2 alleles in corn. The first gene has a dominant allele for yellow kernels (Y) and a recessive allele for white kernels (y). The second gene has a dominant allele for sweet kernels (S) and a recessive allele for starchy (s). In a cross of YYSs x Yyss, what is the chance of having offspring that have yellow and starchy kernels? A. 0 B. 1/4 C. 1/2 D. 1
C. 1/2
If a human female whose father had a recessive X-linked disease has children with a male who is normal, what are the expected genotypes and phenotypes of their predicted offspring by sex? A. All female offspring will be heterozygotes and will not have the disease, all males will have the disease B. All female offspring will be heterozygotes and will not have the disease, 1/2 of the males will have the disease and 1/2 will not have the disease C. 1/2 of the female offspring will be heterozygotes and will not have the disease, 1/2 of the females will be homozygous dominant and will not have the disease, 1/2 of the males will have the disease and 1/2 will not have the disease D. 1/2 of the female offspring will be heterozygotes and will not have the disease, 1/2 of the females will be homozygous recessive and have the disease, 1/2 of the males will have the disease and 1/2 will not have the disease
C. 1/2 of the female offspring will be heterozygotes and will not have the disease, 1/2 of the females will be homozygous dominant and will not have the disease, 1/2 of the males will have the disease and 1/2 will not have the disease
How many genotypes are possible for a character if there are 4 alleles at the gene's loci? A. 2 B. 4 C. 10 D. 20
C. 10
When there is no crossing over, meiosis produces 4 non-recombinant haploid gametes. A single crossover produces ________. A. 4 recombinant diploid gamete B. 4 recombinant haploid gametes C. 2 recombinant haploid gametes and 2 non-recombinant haploid gametes D. 2 recombinant diploid gametes and 2 non-recombinant diploid gametes
C. 2 recombinant haploid gametes and 2 non-recombinant haploid gametes
Cat coat color can be determined by an X-linked gene that can have a black allele or an orange allele. Due to X-inactivation, heterozygote females will show a patchy pattern of orange and black spots called tortoiseshell. A homozyous black female is mated with an orange male. What would be the expected coat colors by sex of their offspring if they had 4 kittens? A. 1 orange female, 1 tortoiseshell female, 2 black males B. 1 black female, 1 tortoiseshell female, 1 black male, 1 orange male C. 2 tortoiseshell females, 2 black males D. All kittens regardless of sex will be black.
C. 2 tortoiseshell females, 2 black males
If in a given DNA sample, 30% of the nucleotides contain thymine, how nucleotides contain cytosine? A. 40% B. 25% C. 20% D. 30%
C. 20%
What is the minimum number of different aminoacyl-tRNA synthetases required by a cell? A. 64, on for each codon B. 61, on for each sense codon C. 20, one for each amino acid D. 4, on for each base (A, U, C, G)
C. 20, one for each amino acid
If the mRNA transcript sequence is 5' A U G C A U G 3', the non-template DNA strand sequence is ____________. A. 3' A T G C A T G 5' B. 5' T A C G T A C 3' C. 5' A T G C A T G 3' D. 3' T A C G T A C 5'
C. 5' A T G C A T G 3'
What RNA sequence is transcribed from the following DNA template strand? 3' A T T G C C A G A T 5' A. 3' U A A C G G U C U A 5' B. 5' T A A C G G T C T A 3' C. 5' U A A C G G U C U A 3' D. 3' T A A C G G T C T A 5'
C. 5' U A A C G G U C U A 3'
A tRNA has the anticodon 3' AUG 5'. What mRNA codon will bind to it? A. 5' AUG 3' B. 3' UAC 5' C. 5' UAC 3' D. 3' AUG 5' E. 3' ATG 5'
C. 5' UAC 3'
In the following diagram, "A" is labeling the end of the _____________. http://s32.postimg.org/v2d49fmsl/Question6.png A. 5' end of the lagging strand B. 5' end of the template strand creating the leading strand C. 5' end of the template strand creating the lagging strand D. 5' end of leading strand E. 3' end of the leading strand F. 3' end of lagging strand G. 3' end of the template strand creating the lagging strand H. 3' end of the template strand creating the leading strand
C. 5' end of the template strand creating the lagging strand
Suppose that some cells are grown in culture in the presence of radioactive nucleotides for many generations so that both strands of every DNA molecule include radioactive nucleotides. The cells are then placed in new medium with nucleotides that are not radioactive so that newly synthesized DNA will not be radioactive. What percentage of DNA molecules will contain radioactivity after 2 rounds of replication? A. 0% B. 25% C. 50% D. 75% E. 100%
C. 50%
Pigs have a diploid number of 38 (2n=38). At the end of anaphase of mitosis, how many chromosomes are present in a pig cell undergoing cell division? A. 19 B. 38 C. 76 D. 46
C. 76
The diploid number for the domesticated dog is 78 (2n=78). For a dog cell at the end of the anaphase II stage of meiosis, how many chromosomes and how many DNA molecules are present (in each cell)? A. 39 chromosomes and 78 DNA molecules B. 39 chromosomes and 39 DNA molecules C. 78 chromosomes and 78 DNA molecules D. 78 chromosomes and 39 DNA molecules
C. 78 chromosomes and 78 DNA molecules
Which of the following statements is TRUE? A. A negative repressible operon is normally OFF and the repressor is in an inactive form so no transcription takes place. B. A negative inducible operon is normally ON and the repressor is in an active form so transcription takes place. C. A negative inducible operon is normally OFF and the repressor is in an active form so no transcription takes place. D. A positive repressible operon is normally OFF and the activator is in an active form so no transcription takes place E. A positive inducible operon is normally ON and the activator is in an inactive form so transcription takes place.
C. A negative inducible operon is normally OFF and the repressor is in an active form so no transcription takes place.
You conduct a three-point testcross in order to determine the order of 3 genes (A, B and C) along a single chromosome. You obtain the following offspring number from your cross. Testcross: Aa Bb Cc x aa bb cc ABC 580 abc 592 ABc 45 abC 40 AbC 89 aBc 94 aBC 3 Abc 5 Total: 1448 Which offspring are the parental genotypes? A. ABC and ABc B. ABc and abC C. ABC and abc D. aBC and Abc
C. ABC and abc
When conducting a testcross to determine the recombination frequency between 2 linked genes (A and B), what would be the appropriate genotypes of the two individuals used for the test cross? A. AABB x aabb B. AaBb x AABB C. AaBb x aabb D. AaBb x AaBb
C. AaBb x aabb
A testcross is conducted involving 2 linked gene, A and B (AaBb x aabb). If the genes are in the repulsion configuration, the 2 most commonly expected genotypes in the offspring would be: A. Aabb and aabb B. Aabb and AaBb C. Aabb and aaBb D. AABB and AaBb E. aaBb and aabb
C. Aabb and aaBb
A testcross is conducted involving 2 linked genes, A and B. If the genes are in the repulsion configuration for the heterozygote, the non-recombinant gametes from the heterozygote will have which 2 combinations of alleles? A. Aa and Bb B. AA and BB C. Ab and aB D. AB and ab
C. Ab and aB
In Labrador retrievers, there is a recessively epistatic gene that will create a yellow lab regardless of the genotype for the hypostatic gene which comes in a dominant black allele to a recessive brown allele Two labs of the following genotypes are mated: Bbee x Bbee. Which of the following are possible colors of their puppies? A. All black B. All brown C. All yellow D. All 3 colors are possible: black, brown, and yello
C. All yellow
Which mechanism allows for more than one polypeptide to be encoded by a single gene? A. Alternative promoters B. RNA interference (RNAi) C. Alternative RNA processing D. Modification of histones E. DNA methylation
C. Alternative RNA processing
In Labrador retrievers, there is a recessively epistatic gene that will create a yellow lab regardless of the genotype for the hypostatic gene which comes in a dominant black allele and a recessive brown allele. In a litter of 8 puppies, the following phenotypes of the puppies were observed: 3 black 4 yellow 1 brown Given these results, what would be the expected genotypes of the parents? A. Bbee x BBEE B. bbee x BBEE C. Bbee x BbEe D. BbEe x BbEe
C. Bbee x BbEe
Albinism is an autosomal recessive disorder that causes lack of pigmentation. Two parents with normal pigmentation have an albino child. What are their genotypes? A. One AA and the other aa B. One Aa and the other aa C. Both Aa D. Both aa E. One Aa and the other AA F. Both AA
C. Both Aa
You are conducting a 3-point test cross of 3 linked genes: A, B and C. In the progeny, the most common genotypes are ABC and abc. The least common are Abc and aBC. Using this information, what is the correct order of the 3 genes along the chromosome? A. BAC only B. CAB only C. Both BAC and CAB D. ACB only E. BCA and ACB
C. Both BAC and CAB
Which of the following CORRECTLY describes ways in which siRNAs and miRNAs regulate genes? A. By binding to complementary DNA and stimulating Slicer-mediated cleavage B. By binding to 5′ UTRs and stimulating Slicer-independent cleavage C. By binding to complementary mRNAs and blocking translation D. By altering chromatin structure via Slicer activity
C. By binding to complementary mRNAs and blocking translation
What is a difference between prokaryotic and eukaryotic chromosomes that might affect the initiation of transcription? A. Eukaryotes do not use promoter regions and prokaryotes do. B. Eukaryotes use DNA polymerase to transcribe RNA while prokaryotes use RNA polymerase. C. Eukaryotes must relax chromatin to allow access to the transcription unit while prokaryotes do not. D. Eukaryotes have no consensus sequences in promoters while prokaryotes do.
C. Eukaryotes must relax chromatin to allow access to the transcription unit while prokaryotes do not.
Eukaryotic gene expression is different from prokaryotic expression in which of the following ways? A. Eukaryotes have operons. B. Prokaryotic DNA associates with histones. C. Eukaryotic DNA forms chromatin. D. Prokaryotes export mRNA from the nucleus.
C. Eukaryotic DNA forms chromatin.
Which one of the following statements concerning prokaryotic and eukaryotic genetics is TRUE? A. Prokaryotic chromosomes have telomere regions. B. Only eukaryotic chromosomes have origin(s) of replication. C. Eukaryotic chromosomes consist of DNA and protein. D. Prokaryotic DNA undergoes crossing over.
C. Eukaryotic chromosomes consist of DNA and protein.
The control of transcriptional activation by GAL4 resembles prokaryotic systems in that: A. GAL4 only binds DNA when it binds its ligand, galactose. B. GAL4 comes off DNA when it binds galactose. C. GAL4 activation is blocked by another protein in the absence of galactose. D. GAL4 activation is blocked by another protein in the presence of galactose.
C. GAL4 activation is blocked by another protein in the absence of galactose.
A child who is blood type A has a mother who is blood type B. In a paternity suit, a man is accused of being the father. He has blood type AB. Is he the father? A. Yes for sure B. No for sure C. He can not be excluded at this point. D. There is a 50% chance he is the father.
C. He can not be excluded at this point.
Griffith's experiments with bacteria added what information to our understanding of DNA? A. He determined that DNA contains four different nitrogenous bases. B. He found that the nitrogen containing components are the genetic material of phages. C. He discovered "the transforming principle" that could genetically alter bacteria. D. He used X-ray diffraction to examine the structure of DNA.
C. He discovered "the transforming principle" that could genetically alter bacteria.
In your genetics lab, you are following the expression of a given gene. In your experiment, you add acetyltransferase to a sample of DNA that contains your gene. Which of the following would you expect to see in your results, assuming you have the techniques to determine the possibilities? A. Histones would become more positive which causes the chromatin to tighten for more gene expression. B. Histones would become less positive which causes the chromatin to tighten for more gene expression. C. Histones would become less positive which causes the chromatin to loosen for more gene expression. D. Histones would become less positive which causes the chromatin to loosen for less gene expression. E. Histones would become more positive which causes the chromatin to loosen for more gene expression.
C. Histones would become less positive which causes the chromatin to loosen for more gene expression.
Which of the following is a FALSE statement comparing mitosis and meiosis? A. Microtubules move chromosomes in both mitosis and meiosis. B. DNA synthesis takes place in both mitosis and meiosis. C. Homologous chromosomes are separated in mitosis but not meiosis. D. Haploid cells are created in meiosis but not mitosis.
C. Homologous chromosomes are separated in mitosis but not meiosis.
Which of the following is a true statement about humans and their chromosomes? A. Human males have 23 pairs of homologous chromosomes. B. Human males are XX for their sex chromosomes. C. Human females have 23 pairs of homologous chromosomes. D. Human males have fewer total chromosomes than human females because they only have 1 X chromosome. E. Human males have 2 copies of every gene on every chromosome.
C. Human females have 23 pairs of homologous chromosomes.
Using the graph, which of the following is an accurate statement? http://s32.postimg.org/4hfc8or1h/question9.png A. In population B, the "B" allele has become fixed by generation 50. B. In population C, the "B" allele has become fixed by around generation 30. C. In population A, the "B" allele has become fixed by generation 50. D. In population A, the "b" allele has become fixed by generation 50.
C. In population A, the "B" allele has become fixed by generation 50.
Morgan crossed a homozygous red eyed female with a white eyed male to create the F1 generation of fruit flies and then proceeded to create a F2 generation. Which result made Morgan think that the locus affecting eye color was on the X chromosome? A. All F1 male and female flies had red eyes. B. All F1 male and female flies had white eyes. C. In the F2, all females had red eyes, and half of the males had red eyes and the other half had white eyes. D. In the F2, half of males and females had red eyes and the other half had white eyes.
C. In the F2, all females had red eyes, and half of the males had red eyes and the other half had white eyes.
Which of the following is a TRUE statement about a gene that is inherited in a classic Mendelian manner of complete dominance? A. Individuals with the recessive phenotype must have at least one parent that is homozygous recessive. B. Individuals with the recessive phenotype must have both parents who are homozygous recessive. C. Individuals with the recessive phenotype must have both parents have at least the heterozygous genotype. D. Individuals with the recessive phenotype must have both parents be true breeders.
C. Individuals with the recessive phenotype must have both parents have at least the heterozygous genotype.
How does histone acetylation affect chromatin? A. It helps the histones have a greater attraction to DNA. B. It inhibits DNA replication by making it more difficult to separate the DNA strands. C. It loosens the chromatin and allows increased transcription by making the histones less positive. D. It loosens the chromatin and allows increased transcription by making the histones more positive.
C. It loosens the chromatin and allows increased transcription by making the histones less positive.
A non-template strand on bacterial DNA has the following base sequence. What amino acid sequence will be encoded by this sequence? 5'-ATGATACTAAGGCCC-3' A. Pro-Gly-Ile-Ile-Val B. Tyr-Tyr-Asp-Ser-Gly C. Met-Ile-Leu-Arg-Pro D. Gly-Pro-(Stop) E. Met-Gln-Arg-Glu-His
C. Met-Ile-Leu-Arg-Pro
In a typical eukaryotic cell, would you expect to find more molecules of H1 histone or more molecules of the H2A histone and why? A. More H1 because nucleosomes contain 2 molecules of H1 and only 1 of H2A B. Equal amounts of H1 and H2A because each nucleosome contains 1 molecule of each. C. More H2A because nucleosomes contain 2 molecules of H2A and only 1 molecule of H1
C. More H2A because nucleosomes contain 2 molecules of H2A and only 1 molecule of H1
Which of the following is NOT an assumption of the Hardy-Weinberg law? A. Large populations B. No natural selection C. Non-random mating D. No gene flow E. No mutations
C. Non-random mating
Match the correct human sex chromosome aneuploidy with the correct statement. X0 A. Sterile male with feminine characteristics B. Fatal C. Only known human viable monosomy D. Phenotypically fertile females E. Phenotypically fertile male
C. Only known human viable monosomy
DNA synthesis during replication is initiated from _______. A. a free 5' OH B. DNA primers C. RNA primers D. telomerase E. DNA polymerase I
C. RNA primers
What is the function of the Shine Dalgarno consensus sequence? A. RNA polymerase binding site during transcription B. DNA polymerase binding site during replication C. Ribosome binding site during prokaryotic protein synthesis D. Spliceosome binding site during post-transcriptional modification E. Marking the site where the transcription should begin
C. Ribosome binding site during prokaryotic protein synthesis
During meiosis in the formation of a human sperm cell, the sex chromosomes do not separate at anaphase 1 so in the resulting daughter cells, one has XY and the other has no sex chromosome. Let's assume all 4 of the sperm from this round of meiosis are used to fertilize 4 different normal egg cells. What are the possible resulting genotypes of the offspring in regards to their sex chromosomes? A. All XO B. All XXY C. Some XO and some XXY D. Some XX, some XY, some XO and some XXY
C. Some XO and some XXY
When DNA is negatively super coiled, which of the following is a TRUE statement? A. The DNA is under-rotated and does not allow transcription easily. B. The DNA is over-rotated and does not allow transcription easily. C. The DNA is under-rotated but allows transcription easily. D. The DNA is over-rotated but allows transcription easily.
C. The DNA is under-rotated but allows transcription easily.
A mistake happens during the cell cycle of a given cell, and it is allowed to enter the M phase directly from the G1 phase, skipping the S and G2 phase. What would you expect to be wrong with this cell at the beginning of mitosis? A. The chromatids would not separate properly and one daughter cell would have more chromosomes than it should. B. The cell is considered haploid instead of diploid. C. The cell would have 1/2 the amount of DNA it should have. D. The cell would have 2x the amount of DNA it should have.
C. The cell would have 1/2 the amount of DNA it should have.
Imagine a drug that can neutralize the positive charges on the tails of histone proteins. Which of the following effects would you expect to see? A. The chromosomes would become more densely packed and more transcription would occur. B. The chromosomes would become more densely packed and less transcription would occur. C. The chromosomes would become less densely packed and more transcription would occur. D. The chromosomes would become less densely packed and less transcription would occur.
C. The chromosomes would become less densely packed and more transcription would occur.
If a bacterial cell was to suddenly run out of any cAMP, would effect on the lac operon would you expect? A. The operon would always be on and would transcribe all of its structural genes because RNA polymerase would bind fully to the promoter region. B. The operon would always be off and would transcribe all of its structural genes because RNA polymerase would bind fully to the promoter region. C. The operon would always be off and would not transcribe any of the structural genes because RNA polymerase would not be able to bind fully to the promoter region. D. The operon would always be on and would transcribe all of its structural genes because RNA polymerase would not be able to bind fully to the promoter region. E. The operon would shut down temporarily until more lactose was available
C. The operon would always be off and would not transcribe any of the structural genes because RNA polymerase would not be able to bind fully to the promoter region.
Which of the following situations will have the MOST progeny in a 3 point test cross between 3 linked genes? A. The progeny resulting from a double cross over event. B. The progeny resulting from a single cross over between the first and middle gene. C. The progeny resulting from no crossing over (i.e. non-recombinant) D. The progeny resulting from a single cross over between the middle and third gene.
C. The progeny resulting from no crossing over (i.e. non-recombinant)
What characteristic would you NOT expect to see in a pedigree of an X-linked recessive trait? A. The trait is more commonly seen in males. B. The trait can skip a generation. C. The trait is commonly passed from fathers to sons. D. Whenever a daughter expresses the trait, the father is affected. E. An affected son's mother either expresses the trait or is heterozygous (carrier).
C. The trait is commonly passed from fathers to sons.
In a certain bacterial gene, transcription fails to initiate properly. What is a possible explanation? A. DNA has not properly unwound from histones. B. The is a mutation in the inverted repeat sequence so that a hairpin can not form. C. There is a mutation at the Pribnow box at the -10 upstream location. D. There is a mutation at the Pribnow box at the -35 upstream location. E. TATA-binding protein (TBP) has not been added yet.
C. There is a mutation at the Pribnow box at the -10 upstream location.
A deletion occurs in a gene that encodes DNA polymerase III so that no functional DNA polymerase III is produced. What will be the most likely consequence of this mutation? A. The DNA strands would contain pieces of RNA. B. The DNA would not exist in a supercoiled state. C. There would be no DNA replication on the leading or lagging strands. D. There would be no RNA primers laid down. E. The DNA will not be able to unwind to initiate replication.
C. There would be no DNA replication on the leading or lagging strands.
The degenerative muscle disease Duchene muscular dystrophy is much more prevalent in human males than human females and the affected males typically come from unaffected parents. This inheritance pattern is most likely: A. X-linked dominant B. autosomal dominant C. X-linked recessive D. autosomal recessive
C. X-linked recessive
If an egg carrying 2 X chromosomes (because of a non-disjunction event) is fertilized by a normal Y carrying sperm, what would be the expected genotype of the resulting offspring and what would be that offspring sex phenotype? A. XY and female B. XY and male C. XXY and male D. XXY and female
C. XXY and male
Because of a non-disjunction event occurring during meiosis, a particular egg has no X chromosome. This egg is fertilized by a normal Y carrying sperm. What is the genotype of the resulting zygote? A. XX B. XXY C. YO D. XO
C. YO
The sister chromatids of diploid cells are separated during the ___________ stage of _____________. A. anaphase I/meiosis I B. anaphase II/meiosis II C. anaphase/mitosis D. anaphase II/mitosis
C. anaphase/mitosis
The function of aminoacyl-tRNA synthetases is to: A. transcribe tRNA genes. B. match tRNA anticodons and mRNA codons at the ribosome. C. attach appropriate amino acids to corresponding tRNAs. D. form the peptide bond between amino acids at the ribosome. E. synthesize and transport amino acids to the ribosomes
C. attach appropriate amino acids to corresponding tRNAs.
The role of sigma factors in bacterial transcription is to _____________. A. determine where RNA polymerase stops transcription B. unwind the DNA to initiate transcription C. bind to the consensus sequences to identify the start site for transcription D. provide the first nucleotide for the mRNA molecule
C. bind to the consensus sequences to identify the start site for transcription
What is the function of cAMP in regulation of the lac operon? A. cAMP joins with a repressor molecule making it inactive so that it can not bind to the lac operon's operator. D. cAMP provides energy that is needed during transcription. C. cAMP joins with catabolite activator protein (CAP) which in turns binds to DNA to allow the proper binding of RNA polymerase for transcription to occur. D. cAMP is an enzyme that will convert lactose into glucose and galactose.
C. cAMP joins with catabolite activator protein (CAP) which in turns binds to DNA to allow the proper binding of RNA polymerase for transcription to occur.
One of the roles of histone proteins in eukaryotes is ___________ A. control of gene expression by preventing digestive enzymes from degrading the DNA. B. allowing microtubules to attach to the kinetochores. C. control of gene expression by allowing transcriptional enzymes variable access to the DNA. D. keeping sister chromatids together until they should separate during cell division.
C. control of gene expression by allowing transcriptional enzymes variable access to the DNA.
A cell with defective __________ would be unable to release the tension generated ahead of the separating DNA template strand. A. helices B. DNA polymerase C. gyrate D. DNA ligase E. nuclease F. primase
C. gyrase
In birds with a ZW sex determining system, the females are: A. cytogametic B. homogametic C. heterogametic D. pleiogametic
C. heterogametic
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Anaphase I A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
C. homologous chromosomes move towards opposite sides of the cell
Which of the following is (are) NOT part of a mature mRNA in eukaryotic cells? A. 5' UTR (leader) B. 5'cap C. introns D. 3'UTR (trailer) E. None of the above are included in the mRNA.
C. introns
tRNA molecules that accept the same amino acids yet have different anticodons are referred to as: A. synonymous tRNAs. B. Wobble tRNAs. C. isoaccepting tRNAs. D. isometric tRNAs/ E. redundant tRNAs.
C. isoaccepting tRNAs.
The ends of linear chromosomes will become shorter on the _________ strands because the _____ ends can not be extended. A. leading; 5' B. leading; 3' C. lagging; 5' D. lagging' 3'
C. lagging; 5'
Which of the following amino acids has a positive charge that helps attract DNA to histones? A. alanine B. glycine C. lysine D. valine E. serine
C. lysine
The reason why sex chromosome number abnormalities are better tolerated in mammals than autosomal aneuploidies is because _________________. A. there are no important developmental genes on the X and Y chromosome B. males really only need the SRY gene present on the Y chromosome to be normal anyway C. mammals already have a built in mechanism of one X-chromosome in each female somatic cell becoming a Barr body so that gene product expression is functionally equal between males and females D. non-disjunction occurs less in the sex chromosomes than the autosomes
C. mammals already have a built in mechanism of one X-chromosome in each female somatic cell becoming a Barr body so that gene product expression is functionally equal between males and females
An operon that is normally not transcribed due to the presence of a repressor, but can be transcribed under certain conditions is known as: A. positive inducible. B. positive repressible. C. negative inducible. D. negative repressible.
C. negative inducible.
Since the lac repressor blocks transcription from the lac operon unless lactose is present, the regulation is characterized as: A. positive inducible. B. positive repressible. C. negative inducible. D. negative repressible.
C. negative inducible.
One of the assumptions for Hardy-Weinberg equilibrium is: A. no dominance B. no crossing over C. no natural selection D. no sexual reproduction
C. no natural selection
Match the stages of mitosis to the description of what is occurring that stage Prometaphase A. chromosomes are arranged at the middle of the cell B. nuclear envelope reforms around each set of daughter chromosomes C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite chromosomes D. sister chromatids separate at the centromere and move towards opposite poles of the cell E. chromosomes initially condense and centrosomes begin to move apart
C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite
If you experimentally shifted the TATA box in eukaryotes to a location 60 base pairs downstream, you would expect the RNA transcript to ______________. A. not form at all. B. occur but the RNA transcript would be 60 nucleotides longer. C. occur but the RNA transcript would be 60 nucleotides shorter. D. initiate properly but not terminate where is should
C. occur but the RNA transcript would be 60 nucleotides shorter.
If glucose and lactose are both present in the environment of E. coli, the lac operon will be _________. A. on and the structural genes will be transcribed B. on and the structural genes will not be transcribed C. off and the structural genes will not be transcribed D. off and the structural genes will be transcribed E. turned into a repressible operon
C. off and the structural genes will not be transcribed
What is one way that eukaryotes do NOT control their gene expression? A. histone modification B. RNA interference C. Operons D. coordinated response elements E. alternative mRNA processing
C. operons
What type of bonds does DNA ligase create between adjacent nucleotides? A. hydrogen B. peptide C. phosphodiester D. ionic
C. phosphodiester
Which of the following enzymes do NOT aid in the unwinding of DNA for replication? A. topoisomerase B. gyrase C. primase D. helicase
C. primase
RNA interference can repress proteins by all of the following mechanisms EXCEPT: A. blocking translation. B. promotin mRNA degradation. C. promoting histone acetylation. D. promoting histone methylation.
C. promoting histone acetylation.
Synapsis of homologous chromosomes occurs during: A. anaphase I B. telophase I C. prophase I D. prophase II
C. prophase I
If a mutation causes a cell to have non-functioning DNA polymerase I, what would that cell NOT be able to do? A. unwind double stranded DNA B. join Okazaki fragments C. remove RNA primers and replace the RNA with DNA D. add DNA nucleotides to the growing daughter strands of new DNA
C. remove RNA primers and replace the RNA with DNA
Which of the following molecules is a considered a catalytic molecule and probably began the evolution of life on Earth? A. DNA polymerase B. DNA C. Ribozyme D. RNA polymerase
C. ribozyme
DNA sequences that are involved in the regulation of transcription in eukaryotes include all of the following EXCEPT: A. the core promoter. B. the regulatory promoter. C. the operator. D. enhancers.
C. the operator.
If a phenotype is described as "wildtype", this phenotype refers to: A. the dominant phenotype B. the recessive phenotype C. the phenotype most commonly occurring in nature D. the phenotype that can only occur in nature
C. the phenotype most commonly occurring in nature
Chargaff's Rules state that in DNA molecules: A. the amount of adenine is equal to the amount of guanine. B. (cytosine amount + guanine amount)/(adenine amount + thymine amount) = 1 C. the amount of uracil in equal to the amount of adenine. D. (adenine amount + guanine amount)/(cytosine amount + thymine amount) = 1
D. (adenine amount + guanine amount)/(cytosine amount + thymine amount) = 1
Assuming the population is in Hardy-Weinberg equilibrium, consider this question: A breeder of exotic tulips find 2 tulips out of 200,000 in his field that show a unique, recessive flower shape. What is the frequency of the flowers that are NOT true-breeding? A. 0.99 B. 0.997 C. 0.003 D. 0.006
D. 0.006
In a population of 500 individuals at a given genetic locus that has 2 alleles (A, a), 235 individuals are homozygous dominant, 215 are heterozygotes and 50 are homozygous recessive. What is the frequency of heterozygotes? A. 0.47 B. 0.1 C. You can not tell from this information D. 0.43
D. 0.43
There are 3 possible alleles represented by p, q and r at a given loci in a population. The frequency of p is 0.2 and the frequency of q is 0.3. What is the frequency of r? A. 0.3 B. 0.2 C. 0.25 D. 0.5
D. 0.5
In a cross of 6 independently assorting genes, the parents' genotypes are: AABBCcDdeeFF (parent #1) x aabbCcddEeff (parent #2). What is the chance one of their offspring would have the genotype of heterozygous for genes A, B, D and F and homozygous recessive for genes C and E? A. 0 B. 1/4 C. 1/8 D. 1/16
D. 1/16
For the same genes in #4, this time assume the genes are slightly further apart. When you test cross a heterozygote for both genes with a homozygous mutant for both genes, you obtain the following progeny: gray/red: 48 gray/purple: 11 black/red: 13 black/purple: 51 How many map units apart are the genes? A. 81 B. 48 C. 52 D. 19.7
D. 19.7
If 2 genes are unlinked, what phenotypic ratio is expected in the progeny of a test cross of a heterozygous individual for both genes with a homozygous recessive for both genes individual? A. 9:3:3:1 B. 12:3:1 C. 3:1 D. 1:1:1:1 E. 9:3:4
D. 1:1:1:1
Which of the following is a correct description of bonds between DNA nitrogenous bases? A. 2 phosphodiester bonds between A and T and 3 hydrogen bonds between C and G B. 3 hydrogen bonds between A and T and 2 hydrogen bonds between C and G C. 2 hydrogen bonds between A and T and 2 phosphodiester bonds between C and G D. 2 hydrogen bonds between A and T and 3 hydrogen bonds between C and G E. 2 phosphodiester bonds between A and T and 3 phosphodiester bonds between C and G
D. 2 hydrogen bonds between A and T and 3 hydrogen bonds between C and G
Each origin of replication has which of the following correct combinations? A. 1 replication fork, 1 leading strand, 1 lagging strand B. 1 replication fork, 2 leading strands, 2 lagging strands C. 2 replication forks, 1 leading strand, 1 lagging strand D. 2 replication forks, 2 leading strands, 2 lagging strands
D. 2 replication forks, 2 leading strands, 2 lagging strands
In guinea pigs, the gene for black (B) fur is dominant over yellow (b) fur. It is known however that a homozygous black genotype is fatal. You bred two black guinea pigs and they have 12 baby guinea pigs that survive. If the offspring follow the expected genotypic/phenotypic ratio, what would you expect for the surviving offspring? A. All offspring would be "bb" and yellow. B. All offspring would be "Bb' and black. C. All offspring would be "BB" and black. D. 2/3 of the offspring would be "Bb" and black and 1/3 would be "bb" and yellow. E. 1/4 of the offspring would be "BB" and black, 1/2 would be "Bb" and black and 1/4 would be "bb" and yellow.
D. 2/3 of the offspring would be "Bb" and black and 1/3 would be "bb" and yellow.
DNA polymerases require all of the following for DNA replication, EXCEPT ____________. A. DNA template B. primer C. free 3' OH D. 3' to 5' polymerase activity E. dNTPs
D. 3' to 5' polymerase activity
Which of the following item(s) is (are) NOT added post-transcriptionally? A. CCA amino acid attachment site of tRNAs B. poly-A tail for an eukaryotic mRNA C. 5' cap for an eukaryotic mRNA D. 5' and 3' UTRs (untranslated regions)
D. 5' and 3' UTRs (untranslated regions)
Which of these sequences could possibly form a hairpin? A. 5′-GGGUUUGGGUUU-3′ B. 5′UUUUUUCCCCCC-3′ C. 5′-ACACACACACAC-3′ D. 5′-GGGGUUUUCCCC-3′
D. 5′-GGGGUUUUCCCC-3′
Which of the following could potentially introduce new alleles into a population's gene pool? A. mutation B. migration (gene flow) C. natural selection D. A and B
D. A and B
In terms of crossing over, which of the following statements is TRUE? A. A crossing over event between the non-sister chromatids of a homologous pair will result in all non-recombinant chromosomes when meiosis is over. B. A crossing over event between the non-sister chromatids of a homologous pair will result in all recombinant chromosomes when meiosis is over. C. A crossing over event between the sister chromatids of a homologous pair will result in 2 recombinant chromosomes and 2 non-recombinant chromosomes when meiosis is over. D. A crossing over event between the non-sister chromatids of a homologous pair will result in 2 recombinant chromosomes and 2 non-recombinant chromosomes when meiosis is over.
D. A crossing over event between the non-sister chromatids of a homologous pair will result in 2 recombinant chromosomes and 2 non-recombinant chromosomes when meiosis is over.
What is a response element? A. A protein that becomes more abundant in response to a stimulus B. A protein that binds DNA during times of stress and activates gene expression C. A short DNA sequence that binds numerous different factors in response to a stimulus D. A short DNA sequence that specifically binds a unique transcription factor
D. A short DNA sequence that specifically binds a unique transcription factor
What is the difference in hydrogen bonding between A/T pairs versus G/C pairs? A. There is no difference in the numbers of hydrogen bonds between G/C pairs and A/T pairs. B. G/C pairs have 1 hydrogen bond and A/T pairs have 2. C. A/T pairs have 3 hydrogen bonds and G/C pairs have 2. D. A/T pairs have 2 hydrogen bonds and G/C pairs have 3.
D. A/T pairs have 2 hydrogen bonds and G/C pairs have 3.
What controls RNA stability in eukaryotic cells? A. 5' cap B. 3' poly(A) tail C. 5' and 3' UTRs D. All of these contribute to RNA stability.
D. All of these contribute to RNA stability.
Enhancers, unlike regulatory promoters, A. do not have to be in a specific location. B. do not have to be in a specific orientation. C. re often transcribed. D. All of these things are true.
D. All of these things are true.
Which of the following is NOT a requirement for Hardy-Weinberg equilibrium? A. Gene flow does not occur B. No mutations C. Random mating D. Allele frequencies must be equal (i.e. p = q) E. Large populations
D. Allele frequencies must be equal (i.e. p = q)
Which of the following statement about regulation of gene expression is CORRECT? A. An inducible gene is transcribed when a specific substance is absent. B. In bacteria, all genes are transcribed at all times as long as they have a functional promoter. C. The regulation of gene expression is the same in both eukaryotes and prokaryotes. D. Bacteria do not have a mechanism for RNA splicing and intron removal by spliceosomes.
D. Bacteria do not have a mechanism for RNA splicing and intron removal by spliceosomes.
Which of the following is an accurate designation for 2 linked genes (A and B) for an individual that is heterozygous for both genes? A. A B a b B. A a B b C. A b a B D. Both A and C
D. Both A and C
If an individual has a recessive genetic disease, you know that _________. A. Both parents must have the disease. B. Both parents must not have the disease. C. One parent at least must have the disease. D. Both parents have to at least be heterozygotes for this gene.
D. Both parents have to at least be heterozygotes for this gene.
Use the following recombination frequencies between pairs of genes to place them along a chromosome. [Gene pair: Recombination Frequency (%)] A and D: 5 D and C: 12 A and C: 7 D and B: 20 C and B: 8 A. B-A-D-C (or C-D-A-B) B. C-D-A-B (or B-A-D-C) C. A-D-C-B (or B-C-D-A) D. D-A-C-B (or B-C-A-D)
D. D-A-C-B (or B-C-A-D)
Match the correct human sex chromosome aneuploidy with the correct statement. Triple-X A. Sterile male with feminine characteristics B. Fatal C. Only known human viable monosomy D. Phenotypically fertile females E. Phenotypically fertile male
D. Phenotypically fertile females
Which of the following elements would NOT be found on an mRNA molecule? A. Protein-coding region B. 3' untranslated region C. 5' untranslated region D. Promoter E. Start and stop codons
D. Promoter
If a cell has a mutation in the gene that creates H1 histone, what effect would you expect to see? A. No centromeres would form but everything else would be ok with the chromosomes. B. No telomeres would form but everything else would be ok with the chromosomes. C. No centromeres or telomeres would form but everything else would be ok with the chromosomes. D. Proper nucleosome formation would not occur along the entire length of the chromosomes.
D. Proper nucleosome formation would not occur along the entire length of the chromosomes.
Which of the following classes of RNAs is unique to the eukaryotes? A. Messenger RNA (mRNA) B. Ribosomal RNA (rRNA) C. Transfer RNA (tRNA) D. Small nuclear RNAs (snRNAs) E. CRISPR RNAa (crRNAs)
D. Small nuclear RNAs (snRNAs)
Which of the following is an example of an epigenetic change in eukaryotes? A. The substitution of an AT base pair by a GC base pair in a gene as a result of a mistake during DNA replication. B. The movement of a promoter region further downstream than where it should be because of a mutation. C. A deletion that removes nucleotides from a gene. D. The addition of methyl groups to cytosines in the promoter region of a gene
D. The addition of methyl groups to cytosines in the promoter region of a gene
In gerbils, the striped allele (S) is dominant over the non-striped alleles (s). A gerbil breeder breeds a gerbil with stripes to a non-striped gerbil. She gets ½ of the offspring with stripes and ½ with no stripes. She really wants all striped gerbils as a pure breeding stock so she breeds 2 striped gerbils hoping to eliminate the non-striped allele eventually but this time, 2/3 of the offspring are striped and 1/3 are not striped. No matter how hard she tries, she can't get pure breeding striped gerbils. What's going on? A. This seems to be a case of recessive epistasis. Somehow the 2 alleles, S and s, are interacting and not allowing true breeding striped individuals. B. This seems to be a case of dominant epistasis. Somehow the 2 alleles, S and s, are interacting and not allowing true breeding striped individuals. C. This seems to be a case of incomplete dominance. Somehow the 2 alleles, S and s, are creating a new phenotype and not allowing true breeding striped individuals. D. This seems to be a case of a lethal allele. The homozygous dominant genotype (SS) must be lethal so when she breeds two striped heterozygotes (Ss), 1/4 of the offspring (SS) will die.
D. This seems to be a case of a lethal allele. The homozygous dominant genotype (SS) must be lethal so when she breeds two striped heterozygotes (Ss), 1/4 of the offspring (SS) will die.
Consider the following pedigree. The filled in shapes indicate an individual who expresses the phenotype. Choose the MOST LIKELY mode of inheritance for the trait. Assume this is a relatively rare allele and that individuals marrying into the family are most likely not carriers. http://s32.postimg.org/nj4u7vp9h/Question1.png A. autosomal recessive B. autosomal dominant C. Y-linked D. X-linked dominant E. X-linked recessive
D. X-linked dominant [This is the most consistent mode of inheritance for this pedigree. Every time a father is affected (I-1, III-7 and III-14), only the daughters are affected. Seven daughters overall are affected, 5 sons are unaffected.]
Consider the following pedigree. The filled in shapes indicate an individual who expresses the phenotype. Choose the MOST LIKELY mode of inheritance for the trait. Assume this is a relatively rare allele and that individuals marrying into the family are most likely not carriers. http://s32.postimg.org/ns2ttn6hx/Question3.gif A. X-linked dominant B. autosomal dominant C. X-linked recessive D. Y-linked E. Autosomal recessive
D. Y-linked
A researcher wants to determine the recombination frequency between 2 linked genes in Drosophila. The first gene is for eye color and the second for wing shape. The researcher finds some mutations in the genes, a yellow mutation (y) for the normally red wild-type (y+) eyes and a bent wing (b) mutation for the wing shape (wild-type, not bent, b+). In order to calculate the recombination frequency, which of the following would be the correct test cross for this researcher to conduct? A. b+b+y+y+ x baby B. b+by+y+ x baby C. bbyy x baby D. b+by+y x baby E. b+b+y+y+ x b+b+y+y+
D. b+by+y x baby
If a bacterial cell had a mutation that made non-functional Rho factor, RNA transcripts would not _______________. A. occur at all B. be able to be elongated properly C. be able to be initiated properly D. be able to be terminated properly
D. be able to be terminated properly
What structures added and/or processed during eukaryotic mRNA editing aids in the binding of the transcript with ribosomes? A. 5' cap only B. poly-A tail only C. intron removal D. both 5' can and poly-A tail
D. both 5' cap and poly-A tail
Which of the following mechanisms allows for more than one polypeptide to be encoded by a single gene? A. alternative cleavage sites B. removal of different introns C. different promoter regions D. both a. and b.
D. both a. and b.
If there is only random mating in a population and no other selection pressures acting on the population, the expected outcome will be that _________ A. allelic frequencies will remain the same but the genotype distribution will change. B. genotypic frequencies will remain the same but the allelic frequencies will change. C. both the genotypic and allelic frequencies will change. D. both the genotypic and allelic frequencies will stay the same. E. No prediction about genotypic and allelic frequencies can be made from one generation to the next
D. both the genotypic and allelic frequencies will stay the same.
You are looking under the microscope at a cell undergoing cell division. You stain your slide with a chemical that will highlight the kinetochores. The areas highlighted would be expected to correspond to which type of chromatin? A. facultative euchromatin B. constitution euchromatin C. facultative heterochromatin D. constitutive heterochromatic
D. constitutive heterochromatic
The TATA box in eukaryotes can be found in the _________ region for a gene. A. terminator B. mediator C. enhancer D. core promoter E. regulatory promoter
D. core promoter
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Prophase I A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
D. crossing over
You have discovered a rare and unusual bacterial species and isolated its DNA. You have allowed this DNA to replicate in the presence of radioactive 15N for many rounds so that all of the DNA now contains the "heavy" form of nitrogen. The DNA is then placed in new medium with nucleotides that are not radioactive (14N) so that newly synthesized DNA will not be radioactive and you allow many rounds of replication with only "light" nitrogen. After conducting a similiar centrifugation procedure like Meselson and Stahl, you discover that every round of replication gives you a single, middle weight band for the nitrogen. This result suggests that this rare species uses ____________. A. semi-conservative DNA replication B. conservative DNA replication C. all 3 methods of DNA replication D. dispersive DNA replication
D. dispersive DNA replication
If translocation does not occur during protein synthesis, which specific process would be prevented? A. transcription B. initiation of translation C. termination of translation D. elongation of translation E. mRNA processing
D. elongation of translation
When a certain allele at a particular gene loci has a frequency of 1.0 in a population, it is considered _____ for that population. A. dominant B. lost C. recessive D. fixed E. balanced
D. fixed
Which of the following would NOT typically increase genetic variation within a population? A. no natural selection for some alleles over others B. mutation C. gene flow (migration into the population) D. genetic drift
D. genetic drift
A cell with defective __________ would not be able to separate the template strands of DNA to begin DNA replication. A. DNA ligase B. primate C. nuclease D. helices E. DNA polymerase
D. helicase
Human males are ___________ for X-linked traits. A. homozygous dominant B. homozygous recessive C. heterozygous D. hemizygous
D. hemizygous
When an all dark purple flower and an all white flower plant are crossed, all of the offspring flowers are a pale lavender. The most logical inheritance pattern to explain this outcome is that the purple allele is: A. dominant B. recessive C. pleiotropic D. incompletely dominant
D. incompletely dominant
A testcross is conducted between two genes that each have a dominant and recessive allele. The progeny show the resulting phenotypes: 50% show the dominant phenotype for both genes and 50% show the recessive phenotype for both genes. This result suggests that the two genes are __________. A. are completely unlinked B. linked but have crossing over 50% of the time C. linked but have crossing over 100% of the time D. linked but have crossing over 0% of the time
D. linked but have crossing over 0% of the time
When a tRNA is undergoing charging, which of the following things is not required? A. amino acid B. aminoacyl-tRNA synthetase C. ATP D. mRNA
D. mRNA
Nucleotides in DNA can be modified by: A. acetylation which increases transcription (gene expression) B. acetylation which decreases transcription (gene expression) C. methylation which increases transcription (gene expression) D. methylation which decreases transcription (gene expression)
D. methylation which decreases transcription (gene expression)
A researcher is studying two populations of squirrels who live on either side of a river and are thus completely separated. In population A, the initial allele frequencies for 2 possible alleles at a single genetic locus were p = 0.3 and q = 0.7. In population B, the initial allele frequencies for the same 2 alleles are p = 0 and q = 1. The researcher transplants several squirrels of both sexes from population A to population B and after a few years, she measures the allele frequencies for p and q in both populations and finds both alleles have a frequency of 0.5. This scenario describes _________. A. natural selection B. mutation C. genetic drift D. migration (gene flow)
D. migration (gene flow)
Consider a single gene which codes for an enzyme that is responsible for the proper breakdown of the amino acid phenylalanine. Phenylketonuria (PKU) is a recessive autosomal disease which is caused by a mutation in the gene for the necessary enzyme. Suffers of the disease show many phenotypic responses to the mutation including intellectual disability, small heads, seizures, skin rashes, fair skin and eyes and behavior problems. This is a good human example of __________. A. polygenic inheritance B. epistasis C. multiple alleles D. pleiotrophy
D. pleiotropy
A CORRECT statement about rRNAs is that they are ________________. A. cleaved and trimmed in eukaryotes but not bacteria B. the least common type of RNA C. methylated in bacteria but not eukaryotes D. processed by intron removal in eukaryotes
D. processed by intron removal in eukaryotes
Which of the following is NOT involved directly in the action of a spliceosome? A. snRNAs B. snRNPs C. pre-mRNA D. rRNA E. branch point
D. rRNA
DNA methylation leads to methyl groups being added to CpG, which in turn: A. recruits acetylases, which lead to chromatin accessibility. B. recruits acetylases, which lead to chromatin inaccessibility. C. recruits deacetylases, which lead to chromatin accessibility. D. recruits deacetylases, which lead to chromatin inaccessibility.
D. recruits deacetylases, which lead to chromatin inaccessibility.
In mammals, milk production is seen only in females. This is an example of a/an: A. Y-linked trait B. X-linked trait C. sex influenced trait D. sex limited trait
D. sex limited trait
Match the stages of mitosis to the description of what is occurring that stage Anaphase A. chromosomes are arranged at the middle of the cell B. nuclear envelope reforms around each set of daughter chromosomes C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite chromosomes D. sister chromatids separate at the centromere and move towards opposite poles of the cell E. chromosomes initially condense and centrosomes begin to move apart
D. sister chromatids separate at the centromere and move towards opposite poles of the cell
Consider two alleles of a single gene that shows complete dominance, one dominant allele for black fur (B) and the other recessive allele for brown fur (b) in gerbils. You mate a black gerbil of unknown genotype with a brown gerbil. 1/2 of the offspring are black and 1/2 are brown. This type of mating is called a __________ and your results tell you the genotype of the parental black gerbil was __________ A. test cross/BB. B. back cross/Bb. C. reciprocal cross/Bb. D. test cross/ Bb.
D. test cross/Bb.
The function of the rho protein is: A. to help terminate translation B. to help RNA polymerase to bind to DNA C. to help RNA polymerase find a promoter D. to help terminate transcription
D. to help terminate transcription
The 5′ cap on an mRNA is important for all the processes listed below EXCEPT for the _________ of an mRNA molecule. A. stability B. initiation of translation C. ribosomal interaction D. transcription
D. transcription
The Hershey Chase experiment demonstrated that: A. bacteria used DNA as the molecule of heredity. B. bacteria did not use proteins as the molecule of heredity. C. viruses used proteins as the molecules of heredity. D. viruses used DNA as the molecule of heredity.
D. viruses used DNA as the molecule of heredity.
Consider three independently assorting genes, A/a, B/b, and C/c. What is the probability of obtaining an offspring that is AABbCc from parents that are AaBbCC and AABbCc? A. 1/4 B. 1 C. 0 D. 1/2 E. 1/8
E. 1/8
In a given population for a given gene, there are 40 homozygous dominant individuals, 30 heterozygotes and 80 homozygous recessive. What is the percentage of homozygous dominant? A. 20% B. 53% C. 33% D. 25% E. 27%
E. 27%
If the sequence of one strand of a DNA molecule is 5' ATGGCAT3", the complementary strand sequence would be: A. 5" ATGGCAT 3' B. 3' ATGGCAT 5' C. 5' TACCGTA 3' D. 3' UACCGUA 5' E. 3' TACCGTA 5' F. 5' UACCGUA 3'
E. 3' TACCGTA 5'
Following a monohybrid cross of 2 F1 offspring, what are the possible genotypes in the F2 offspring? (Using "A" to represent the dominant allele and "a" to represent the recessive allele) A. Only AA or aa B. Only aa C. Only AA D. Only Aa E. AA, Aa, or aa
E. AA, Aa, or aa
Which of the following events of meiosis creates genetic variation among the gametes? A. Crossing over B. Independent assortment of maternal and paternal chromosomes C. Separation of homologues so that each gamete only gets one copy of each chromosome D. Only A. and B. E. All of the above
E. All of the above
What is a way you could DECREASE transcription in eukaryotes? A. Cause a mutation in the TATA box B. Cause a mutation in RNA polymerase II C. Move the regulatory promoter region far downstream from the transcription unit D. Alter chromatin structure so it is more compact E. All of these actions would inhibit transcription
E. All of these actions would inhibit transcription
In Avery and Griffiths' experiments, they demonstrated: A. harmless bacteria could become pathogenic by picking up material from pathogenic strains. B. proteins did not serve as the molecule of heredity. C. RNA did not serve as the molecule of heredity. D. DNA served as the molecule of heredity. E. All of these options are correct.
E. All of these options are correct.
In a _________ operon, the regulatory protein is referred to as a repressor. A. negatively repressible B. negatively inducible C. positively repressible D. positively inducible E. Both a. and b. are correct
E. Both a. and b. are correct.
Which of the following terms is least relevant to the assembly of basal transcription apparatus for transcription? A. Core promoter B. General transcription factors C. TATA box D. RNA polymerase E. Enhancer
E. Enhancer
A researcher is trying to determine the pattern of gene expression for a group of 5 genes. She is able to measure the amount of DNA methylation levels of the 5 genes. The table below shows her results with a greater number of plus signs indicating a higher level of methylation. Based on this information, which of the genes would you expect to have the highest rate of transcription and thus the most gene expression? Gene: Methylation Level 1: +++ 2: +++++ 3: ++++ 4: ++ 5: + A. Gene 1 B. Gene 2 C. Gene 3 D. Gene 4 E. Gene 5
E. Gene 5
Which of the following statements is FALSE regarding TFIID? A. It contains a TATA binding protein. B. It aids in initiation of transcription. C. It binds to the core promoter. D. It binds to the TATA box. E. It is a transcriptional activator protein.
E. It is a transcriptional activator protein.
An mRNA has the stop codon 5' UAA 3'. What tRNA anticodon will bind to it? A. 5' AUU 3' B. 5' ATT 3' C. 3' AUU 3' D. 3' ATT 3' E. No anti-codon will bind.
E. No anti-codon will bind.
tRNA molecules: A. form extensive and variable tertiary structures. B. are comprised of only the standard four nucleotides. C. have a triplet parallel codon that interacts with mRNA. D. have their amino acid attached covalently at the 5' end. E. None of the above
E. None of the above.
Match the correct human sex chromosome aneuploidy with the correct statement. XYY A. Sterile male with feminine characteristics B. Fatal C. Only known human viable monosomy D. Phenotypically fertile females E. Phenotypically fertile male
E. Phenotypically fertile male
An individual with the genotype AaBb is test-crossed with an individual with the genotype aabb. Four classes of offspring are produced in equal frequencies: 25% AaBb; 25% Aabb; 25% aaBb and 25% aabb. Which of the following statements is TRUE about this cross? A. The A and B genes must be linked and are very close together. B. The A and B genes must be on the same chromosome but very far apart. C. The A and B genes must be on the same chromosome, about 10 map units apart. D. The A and B genes must be on different chromosomes. E. The A and B genes could be on the same chromosome but very far apart or could be on different chromosomes.
E. The A and B genes could be on the same chromosome but very far apart or could be on different chromosomes.
What would happen to the lac operon if there was a mutation in the lacI promoter region of the regulatory gene so that no repressor would ever be made? A. The lac operon would always be off and would transcribe all the structural genes only if lactose was present. B. The lac operon would always be on and would transcribe all the structural genes only if lactose was absent. C. The lac operon would always be on and would transcribe all the structural genes only if lactose was present. D. The lac operon would always be off and would transcribe all the structural genes only if lactose was absent. E. The lac operon would always be on and would transcribe all the structural genes regardless if lactose was present or not.
E. The lac operon would always be on and would transcribe all the structural genes regardless if lactose was present or not.
A certain organism has a mutation in the shelterin gene that makes it non-functional. Which of the follow consequence would you expect from this mutation? A. Nucleosomes would not be formed so DNA can not be compacted as tightly. B. Epigenetic control would not be possible. C. The phosphodiester bonds between nucleotides would not be formed. D. DNA could not be repaired if it underwent damage. E. The telomere overhand region would become accidentally repaired, thus lengthening the chromosomes unintentionally.
E. The telomere overhand region would become accidentally repaired, thus lengthening the chromosomes unintentionally.
Which of the following statements describes 'wobble' correctly? A. There is flexible pairing between tRNA and the amino acids as there are more tRNAs than the number of amino acids. B. There are not enough tRNA's for all 20 amino acids. C. The third base pair rules between template DNA and mRNA is relaxed. D. There are codons that can code for more than one amino acid. E. The third base pair rules between the tRNA and mRNA is relaxed.
E. The third base pair rules between the tRNA and mRNA is relaxed.
If a sample of single stranded DNA has 18% guanine, the expected amount of adenine in this sample is: A. 18% B. 25% C. 32% D. 36% E. You can not tell from this information alone.
E. You can not tell from this information alone.
Consider the following pedigree. The filled in shapes indicate an individual who expresses the phenotype. Choose the MOST LIKELY mode of inheritance for the trait. Assume this is a relatively rare allele and that individuals marrying into the family are most likely not carriers. http://s32.postimg.org/atjwgi8px/Question2.gif A. Y-linked B. Autosomal dominant C. X-linked dominant D. X-linked recessive E. autosomal recessive
E. autosomal recessive
Match the stages of mitosis to the description of what is occurring that stage Prophase A. chromosomes are arranged at the middle of the cell B. nuclear envelope reforms around each set of daughter chromosomes C. nuclear envelope disintegrates and the sister chromatids become attached to microtubules from opposite chromosomes D. sister chromatids separate at the centromere and move towards opposite poles of the cell E. chromosomes initially condense and centrosomes begin to move apart
E. chromosomes initially condense and centrosomes begin to move apart
Imagine there is a biochemical pathway in bacteria that converts Molecule A into Molecule Z. This conversion requires 3 enzymes and they are coded for by structural genes in an operon system. In this operon, when Molecule Z binds with a regulatory protein, the operon is shut "off" and the structural genes are not transcribed. Molecule Z is thus referred to as a/an _______ and this is a/an ________ operon. A. activator; repressible B. co-repressor; inducible C. repressor; inducible D. repressor; repressible E. co-repressor; repressible
E. co-repressor; repressible
Which of the following does NOT enhance the binding of the ribosome to the 5' end of eukaryotic mRNA? A. 5' cap B. 3' poly-A tail C. cap binding proteins D. poly(A) proteins E. enhancer
E. enhancer
In a strand of DNA, a ________ bond connects the phosphate group of one nucleotide to the sugar of the adjacent nucleotide. A. peptide B. sugar C. hydrogen D. phosphate E. phosphodiester
E. phosphodiester
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Anaphase II A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
E. sister chromatids separate
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Telophase I A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
F. separated chromosomes reach end of the cell
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Metaphase I A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
G. homologous pairs of chromosomes line up at the metaphase plate
For the stages of Meiosis I and II below, match the stage with the correct description of events during that stage. Metaphase II A. spindle fibers form inside haploid cells B. spindle fibers break down in haploid cells without duplicated chromosomes C. homologous chromosomes move towards opposite sides of the cell D. crossing over E. sister chromatids separate F. separated chromosomes reach end of the cell G. homologous pairs of chromosomes line up at the metaphase plate H. chromosomes line up at the metaphase plate with sister chromatids on each side
H. chromosomes line up at the metaphase plate with sister chromatids on each side
An analysis of a sample of nucleic acids reveals that it has 30% adenine, 21% guanine, 22% thymine and 27% cytosine. This sample is most likely a ________________. A. double stranded DNA molecule B. single stranded DNA molecule C. single stranded RNA molecule D. double stranded RNA molecule
b. single stranded DNA molecule
Jennifer and Steve are both heterozygotes for the autosomal recessive disease sickle cell anemia. Their first born child has sickle cell disease. Jennifer is pregnant with their second child. What is the chance BOTH children will have sickle cell disease (i.e. Child 1 has sickle cell, AND child 2 has sickle cell.)? A. 1/2 B. 1/4 C. 1/8 D. 1/16
d. 1/16
A human with XXY sex chromosomes would have a diploid number of ____ and would appear phenotypically as _______ A. 45/female. B. 45/male. C. 46/male. D. 47/male.
d. 47/male
Is a cell haploid or diploid at anaphase II of meiosis II?
haploid
The________ is a type of regulator protein that binds to a region of DNA in the promoter of a gene called the operator and prevents transcription from taking place. A. inducer B. repressor C. activator D. terminator
repressor