Genetics Final

In the above diagram, each white box represents a gene, and four of these are numbered (#1#4). Which of the following is true? A) #1 and #2 could be different alleles of the same gene B) #2 and #3 could be different alleles of the same gene C) #3 and #4 could be different alleles of the same gene D) #1, #2, and #3 could be three different alleles of the same gene None of the above

#1 and #2 could be different alleles of the same gene

An E. coli merodiploid has the following genotype: lacI- lacO+ lacZ+ lacY- lacA- / F' lacI+ lacOc lacZ- lacY+ lacA+ What is this strain's phenotype without and with IPTG? A) - IPTG: LacZ- LacY+ LacA+ + IPTG: LacZ- LacY+ LacA+ B) - IPTG: LacZ+ LacY- LacA- + IPTG: LacZ- LacY+ LacA+ C) - IPTG: LacZ- LacY- LacA- + IPTG: LacZ+ LacY+ LacA+ D. - IPTG: LacZ- LacY+ LacA+ + IPTG: LacZ+ LacY+ LacA+ E. - IPTG: LacZ- LacY- LacA- + IPTG: LacZ- LacY- LacA-

- IPTG: LacZ- LacY+ LacA+ + IPTG: LacZ+ LacY+ LacA+

A husband and wife have normal vision, although both of their fathers are red-green colorblind, an X-linked recessive condition. The wife is pregnant with a daughter. What is the likelihood that this child will be colorblind? A) 0 B) 1/8 C) 2/9 D) 1/4 E) 3/4

0

The p value for this analysis is in the range of: A) 0.90 - 0.50 B) 0.50 - 0.20 C) 0.20 - 0.05 D) 0.05 - 0.01 E) 0.01 - 0.001

0.90 - 0.50

If individuals II-2 and II-4 were to have a child, what is the likelihood the child would be affected by this condition? (A) 1/9 (B) 1/4 (C) 1 (D) 1/2 (E) 0

1/4

If individuals II-5 and II-6 had a third child, what is the likelihood that this child would be a carrier female? A) 0 B) 1/8 C) 1/4 D) 1/3 E) 1/2

1/4

If individuals II-4 and II-5 were to have a child, what is the probability that their child would be male and be affected by this condition? I. 1 is a circle and is blank I. 2 is a square and is blank I. 3 is a circle and is blank I. 4 is a square and is blank II. 1 is a circle and blank II. 2 is a square and is filled II. 3 is a circle and is filled II. 4 is a square and is blank II. 5 is a circle and is blank II. 6 is a square and is filled II. 7 is a circle and is filled II. 8 is a square and is blank (A) 1/8 (B) 1/9 (C) 0 (D) 1/36 (E) 1/18

1/18

In chickens, there is a condition known as "creeper," in which the bird has very short legs and wings and appears to be "creeping" when it walks. Creeper chickens never breed true, and if a creeper is bred to a wild-type chicken, approximately half of the offspring will be creepers and the other half will be wild type. Based on what you have learned, if you mated two creeper chickens together, what is the likelihood that you would get a wild-type offspring? (A) 2/3 (B) 1/3 (C) 1/2 (D) 1/4 (E) 1

1/3

From a cross between two individuals with the above genotype (AABbccDdEe x AABbccDdEe), what proportion of the progeny would you expect to have the genotype AAbbccddEe? A) 27/64 B) 9/16 C) 3/4 D) 1/2 E) 1/32

1/32

In Labrador retriever dogs, coat color is controlled by the B and E genes. B (black) is dominant to b (brown), and E is recessive epistatic to B. In a cross between Bb; ee and bb; Ee individuals, what is the likelihood that their second puppy will have a black coat? (A) 1/4 (B) 3/16 (C) 1/2 (D) 9/16 (E) 4/16

1/4

The following Punnett square shows the F2 offspring from one of Mendel's dihybrid crosses (a=axial; d=dwarf). If you were to set up a cross between plants from the two starred boxes, what proportion of their progeny should be tall plants with axial flowers? AD Ad aD ad x AD Ad aD ad What will be the ratio of the 2nd box in the 3rd column and the last box in the last column? (A) 5/16 (B) 1/2 (C) 3/4 (D) 1/4 (E) 1/8

1/4

From a cross between two tetrahybrid individuals with the genotype AaBbCcDd, what proportion of their progeny should you expect to have the genotype aaBBCcDd? (A) 1 (B) 1/32 (C) 1/64 (D) 0 (E) 1/128

1/64

Red hair is a recessive autosomal trait. The MN blood type system is controlled by the autosomal L gene. The alleles LM and LN are codominant with one another, and heterozygotes express both M and N antigen on their red blood cells. What is the probability that a red-haired woman with MN antigen phenotype and a brown-haired man (who is a carrier for the red allele) with an MN antigen phenotype will have a red-haired child with an N antigen phenotype? A) 0 B) 1/4 C) 1/8 D) 1/16 E) 1/32

1/8

In a testcross between a+/+b and ab/ab flies, what proportion of the progeny would you expect to have a wild-type phenotype if these genes are 20 cM apart? (A) 0% (B) 5% (C) 10% (D) 20% (E) 50%

10%

The Drosophila yellow gene is located on the X chromosome, and it is haplosufficient. Wild-type flies have gray bodies, and flies with homozygous loss-of-function yellow alleles have yellow bodies. You cross a true-breeding gray female to a yellow male. What ratio of phenotypes and sexes should you expect in their offspring? A) 1:1 yellow females : gray males B) 1:1 gray females : yellow males C) 1:1 gray females : gray males D) 3:1 gray females: yellow males E) 1:2:1 gray females : gray males : yellow females

1:1 gray females : gray males

If you perform the above cross in the reciprocal direction, with a true-breeding yellow female and a gray male, what ratio of phenotypes and sexes should you expect in their offspring? A) 1:1 yellow females : gray males B) 1:1 gray females : yellow males C) 1:1 gray females : gray males D) 3:1 gray females: yellow males E) 1:2:1 gray females : gray males : yellow females

1:1 gray females : yellow males

Assuming Mendel's four postulates are being followed, what phenotypic ratio would you expect to see in the progeny of this testcross? A) 9:3:3:1 B) 9:3:4 C) 1:2:1 D) 1:1:1:1 E) 1:1:4:4

1:1:1:1

The progeny resulting from a cross between two individuals that are heterozygous for a Mendelian trait will exhibit a _______ genotypic ratio and a _______ phenotypic ratio. A) 1:2:1 ; 3:1 B) 1:2:1 ; 1:2:1 C) 1:1:1:1 ; 9:3:3:1 D) 3:1 ; 9:3:3:1 E) 1:2:2:1; 3:3:3:1

1:2:1 ; 3:1

Perform a chi-square analysis of this dataset. How many degrees of freedom are there in your analysis? A) 0 B) 1 C) 2 D) 3 E) 4

2

The following figure shows the results of DNase digestion of chromatin. How many nucleosomes are present in the ~400 base-pair (bp) band? A) 1 B) 2 C) 3 D) 4 E) 5

2

You have a red molecule that specifically binds to inactivated X chromosomes (Barr bodies), and a blue molecule that binds to all X chromosomes. You apply these two molecules to cheek cells from an atypical human male with an XXXY karyotype. When looking at these cells under the microscope, you should see ___ red signals and ___ blue signals in the nucleus of each cell. A) 0 ; 1 B) 0 ; 3 C) 1 ; 3 D) 2 ; 3 E) 3 ; 3

2 ; 3

Imagine that you are strolling through Mendel's garden observing the results one of his dihybrid cross experiments involving stem height (where tall is dominant over dwarf) and flower color (where violet is dominant over white). You select an F2 plant that has a tall stem and violet flowers. What is the probability that this F2 plant has the genotype DDWw? A) 3/16 B) 1/4 C) 9/16 D) 4/9 E) 2/9

2/9

Assume the mass of DNA in a Drosophila gamete is 50 picograms. How many picograms of DNA should a typical Drosophila cell contain in G2? (A) 400 (B) 100 (C) 200 (D) 25 (E) 50

200

A human sperm contains ___ autosomes and ___ sex chromosomes. A) 22 ; 1 B) 22 ; 2 C) 23 ; 2 D) 44 ; 2 E) 46 ; 1

22 ; 1

In razorback hogs, coat color is under the control of multiple genes. For the red gene, the wild-type R allele (brown hair phenotype) is dominant over the r allele (red hair phenotype). However, a recessive allele of a second gene e is epistatic to the red gene: ee hogs always have white hair, regardless of the genotype of the red gene. In a cross between two Rr; Ee hogs, what is the likelihood that a given offspring will have red hair? A) 1/16 B) 2/16 C) 3/16 D) 4/16 E) 9/16

3/16

Consider a trihybrid cross involving three of Mendel's seven pairs of traits (stem height, flower color, and pea pod shape), where the dwarf height (d), white flower color (w) and constricted pod shape (c) alleles are recessive. What proportion of the progeny from the cross DdWwCc x DdWwCc will be dwarf plants with white flowers and full pea pods? A) 1/64 B) 3/64 C) 6/64 D) 9/64 E) 27/64

3/64

The ability to taste the chemical phenylthiocarbamide is an autosomal dominant phenotype, and the inability to taste it is recessive. If a taster man (with a nontaster mother) has a child with a taster woman (who in a previous relationship had a nontaster son), what is the probability that this child will be a taster and girl? A) 0 B) 1/8 C) 2/9 D) 3/8 E) 3/4

3/8

Referring to the question directly above, what would you expect if you measured Ade2 activity in individual cells where ADE2 was moved to the tested location, instead of measuring the activity of the entire culture? A) All of the cells would have 32% of wild-type Ade2 activity. B) Half of cells will have 64% of wild-type Ade2 activity, and half will have no Ade2 activity. C) All of the cells would have no Ade2 activity. D) 68% of the cells would have full Ade2 activity, and 32% would have no Ade2 activity. E) 32% of the cells would have full Ade2 activity, and 68% would have no Ade2 activity.

32% of the cells would have full Ade2 activity, and 68% would have no Ade2 activity

Genes q and r are located on the same chromosome, 20 map units apart. You perform a testcross with a Qr/qR individual and observe 360 offspring. How many of these offspring should you expect to display a double-recessive phenotype? A) 20 B) 36 C) 40 D) 72 E) 80

36

House flies (Musca domestica) are diploid (2n=12). How many chromosomes will be present in a gamete of a house fly? A) 2 B) 4 C) 6 D) 12 E) 24

6

You are characterizing a new mutation in fruit flies that causes a blue-eye (b) phenotype. You have a true-breeding line that has blue eyes and curved wings, and when you cross these to wild-type flies, all the F1 progeny appear wild type (red eyes and straight wings). You cross these F1 dihybrids back to your original true-breeding blue-eyed, curved wings strain and you obtain the following F2 progeny. 154 red-eyed, straight wings 148 blue-eyed, curved wings 115 blue-eyed, straight wings 111 red-eyed, curved wings You perform a chi-square analysis and conclude that these two genes do not show independent assortment. Based on these data, you can conclude that these two genes are located ____ cM apart. A) 12 B) 23 C) 43 D) 49 E) 55

43

The following is a template strand DNA sequence: 5'-ATTGGTAACTG-3' Which of the following would be the product of transcription? A) 5'-ATTGGTAACTG-3' B) 5'-AUUGGUAACUG-3' C) 5'-CAGTTACCAAT-3' D) 5'-CAGUUACCAAU-3' E) None of the above.

5'-CAGUUACCAAU-3'

The complementary sequence of 5'-GCGCAAATTATGCGGA-3' is ... A) 5'-TCCGCATAATTTGCGC-3' B) 5'-CGCGTTTAATACGCCT-3' C) 3'-GCGCAAATTATGCGGA-5' D) 3'-ATATGGGCCGCATAAG-5' E) 5'-GCGCAAATTATGCGGA-3'

5'-TCCGCATAATTTGCGC-3'

You suspect that your pet ball python, although normally pigmented, is a carrier of the recessive albinism trait. You have allowed her to mate with an albino male snake, and the first of the resulting eggs is about to hatch. If you are correct about your snake's genotype, what is the probability that the first snake that hatches will be albino? A) 0% B) 25% C) 50% D) 75% the probability cannot be predicted from this information

50%

If you were to perform a test cross using the above F2 plant (genotype DDWw), what proportions of phenotypes would you expect to observe in the testcross progeny? A) 100% tall and violet B) 50% tall and violet, 50% tall and white C) 50% dwarf and violet, 50% tall and violet D) 25% tall and violet, 25% tall and white, 25% dwarf and violet, 25% dwarf and white 75% tall and violet, 25% dwarf and white

50% tall and violet, 50% tall and white

Biotin is an essential vitamin in humans that wild-type E. coli can naturally produce. You have been isolating and analyzing E. coli mutants that cannot grow in the absence of biotin. Your biochemist friend has kindly provided you with intermediates in the pathway. You analyzed the growth of each mutant when given each supplement, and marked growth with "+" and no growth with a "-". The results are below: Based on the feeding experiment, what is biochemical pathway for biotin biosynthesis? A) DAPA -> DTB -> 7-KAP -> biotin B) DTB -> DAPA -> 7-KAP -> biotin C) DAPA -> 7-KAP -> DTB -> biotin D) 7-KAP -> DAPA -> DTB -> biotin E) 7-KAP -> DTB -> DAPA -> biotin

7-KAP -> DAPA -> DTB -> biotin

Red hair in humans is a recessive trait caused by a mutant allele of the MC1R gene, which regulates pigment production in skin and hair. If a non-red-haired woman and a non-red-haired man have one red-haired child, what is the probability that their next child will not have red hair? A) 0% B) 25% C) 50% D) 75% E) 100%

75%

How many different gamete types can be produced by an individual with the genotype AABbccDdEe? A) 2 B) 4 C) 8 D) 16 E) 32

8

What blood types are theoretically possible to see in the offspring of a woman with type A blood and a man with type B blood? (A) Only AB (B) Only O (C) A or B (D) A, B, or AB (E) A, B, AB, or O

A, B, AB, or O

What blood types are theoretically possible to see in the offspring of a woman with type AB blood and a man with type B blood? (A) Only O (B) A, B, AB, or O (C) A or B (D) Only AB (E) A, B, or AB

A, B, or AB

The sketch below represents a replication fork. Based on the letters, what are the correct terms for each component? A) A: leading strand; B: Okazaki fragment (DNA); C: primer (RNA); D: lagging strand; E: template strand B) A: template strand; B: primer (RNA); C: Okazaki fragment (RNA); D: lagging strand; E: leading strand C) A: template strand; B: Okazaki fragment (RNA); C: primer (DNA); D: lagging strand; E: leading strand D) A: template strand; B: Okazaki fragment (DNA); C: primer (RNA); D: lagging strand; E: leading strand E) A: template strand; B: Okazaki fragment (RNA); C: primer (RNA); D: lagging strand; E: leading strand

A: template strand; B: Okazaki fragment (DNA); C: primer (RNA); D: lagging strand; E: leading strand

Consider the following weird pedigree. What is the most likely genotype of individual III-5? (A) AA (B) Aa (C) A/a (D) aa (E) It is impossible to make any sort of educated guess based on this pedigree alone.

AA

In summer squash, white fruit (A) is dominant over yellow (a), and disk-shaped fruit (B) is dominant over sphere-shaped fruit (b). A cross between a plant producing white, disk fruit and a plant producing yellow, sphere fruit produces progeny with the following phenotypes: 1/4 white, disk 1/4 white, sphere 1/4 yellow, disk 1/4 yellow, sphere From the above information, the genotypes of the parents must be: A) AABb x aabb B) Aabb x Aabb C) aaBB x AAbb D) AaBb x Aabb E) AaBb x aabb

AaBb x aabb

How does Barbara McClintock's Ac element "activate" Ds, allowing it to mobilize? A) Ac is a transcriptional activator of the transposase gene of Ds. B) Ac provides functional transposase enzyme that allows Ds to mobilize. C) Ac repairs the defective inverted repeats of Ds. D) Ac activates the enzyme responsible for purple kernel formation. E) Ac relaxes heterochromatin to un-silence Ds.

Ac provides functional transposase enzyme that allows Ds to mobilize

In general, what are the consequences of balanced homozygous translocations? A) Affected individuals would experience severe phenotypic defects, including sometimes lethality. B) Affected individuals would experience no immediate effects on phenotype, but would be semi-sterile. C) Affected individuals would experience no immediate effects on either phenotype or reproduction, but offspring would likely be semi-sterile. D) Affected individuals would experience semi-useful superpowers, like being able to sit through an entire Harry Potter movie marathon without needing to use the bathroom. E) Affected populations would note recombination suppression.

Affected individuals would experience no immediate effects on either phenotype or reproduction, but offspring would likely be semi-sterile

Which of the following is not true about genes? (A) Genes are DNA sequences (except in some viruses) (B) All genes have some effect on phenotype (C) All genes encode messenger RNAs (D) Genes are located on chromosomes (E) Genes are located in the nuclei of eukaryotic cells

All genes encode messenger RNAs

For Barbara McClintock's Ac/Ds system, let's assume the Ds element is currently inserted into the c gene, leading to the white (mutant) kernel phenotype. What is the expected phenotype for the kernels if you deleted only the inverted repeat sequences of the Ds element? A) The kernels would spontaneously combust into popcorn. B) Purple spots would randomly appear on the kernels. C) White spots would randomly appear on the kernels. D) All kernels would remain white. E) All kernels would revert to completely purple.

All kernels would remain white

The human genome contains ~25,000 protein-coding genes, yet has the capacity to produce several hundred thousand proteins. Which of the following can account for the vast difference in gene number and protein number? A) Alternative splicing. B) Exon shuffling. C) There are more introns than exons. D) There are more exons than introns. E) Most genes have multiple start sites and overlapping reading frames.

Alternative splicing

You have discovered a new kinase named "Awe" that phosphorylates "Some". You hypothesize that a surface-exposed Glutamic Acid (Glu-183) residue on Awe is necessary for the Awe-Some protein-protein interaction. If your hypothesis is correct, substituting Awe Glu-183 for which amino acid would be most likely to disrupt the interaction? A) Arginine B) Valine C) Aspartic Acid D) Leucine E) Serine

Arginine

A Labrador retriever that is a "carrier" of the recessive brown coat allele will produce gametes of which of the following genotypes? A) B and b B) BB, bb, and Bb C) B only D) b only E) Bb only

B and b

Which of the following is a true difference between bacterial and eukaryotic genomes? A) Bacteria tend to have linear chromosomes, while eukaryotes tend to have circular chromosomes. B) Eukaryotes often carry extra-chromosomal DNA in the form of plasmids, while plasmids generally do not occur in bacteria. C) Bacteria tend to rely solely on supercoiling to package their DNA, while eukaryotes require nucleosomes. D) Eukaryotes tend to be haploid, while bacteria tend to be diploid. E) None of those statements are true differences.

Bacteria tend to rely solely on supercoiling to package their DNA, while eukaryotes require nucleosomes

Why do bacterial mRNAs, but not eukaryotic mRNAs, require a Shine-Dalgarno sequence? A) The eukaryotic poly-A tail serves the same function. B) Bacterial mRNAs are shorter lived. C) Eukaryotic mRNAs must exit the nucleus. D) Bacterial mRNAs are often polycistronic. E) mRNA splicing would remove Shine-Dalgarno sequences.

Bacterial mRNAs are often polycistronic

Which of the following would you not expect to find as constitutive heterochromatin? A) centromere. B) telomere. C) highly repetitive DNA. D) Barr body. E) All of the above would be found in regions of constitutive heterochromatin.

Barr body

Why is lacZ required for lacY induction by lactose, but not IPTG? A) Because LacZ is a transcriptional regulator of lacY. B) Because LacZ produces cAMP required for induction. C) Because LacZ produces allo-lactose required for induction. D) Because LacZ allosterically inactivates the LacI repressor. E) None of the answers are correct.

Because LacZ produces allo-lactose required for induction

Why are heterozygous inversions said to suppress genetic recombination? A) Because gametes resulting from crossing-over within the inverted region are unbalanced. B) Because crossing-over physically can never occur within an inversion. C) Because inversions lead to reduced expression of the recombinase enzymes. D) Because inversions make potential mates less attractive. E) Because inversions damage the reproductive tract of females.

Because gametes resulting from crossing-over within the inverted region are unbalanced

In the above diagram, crossing over might occur between which chromatids? A) Between A and B B) Between B and C C) Between C and D D) Between D and E None of these would recombine.

Between A and B

Based on the results from the question above, which enzyme is responsible for producing DAPA? A. BioA B. BioD C. BioB D. Wild Type E. none of the above

BioA

You have isolated E. coli mutants deficit in serine biosynthesis, and you have identified compounds A, B, and C as intermediates in serine biosynthesis. Based on the feeding experiment below, which enzyme is responsible for producing Compound A? (Note: +/- refers to growth or no growth, respectively; and mutant bioA corresponds to enzyme BioA, etc.). A) BioB B) Wild Type C) BioD D) Not enough information E) BioA

BioD

Genes A, B, and C are located on human chromosomes 17. You perform three linkage mapping experiments, and you determine that genes A and B are 7 m.u. apart, genes A and C are 12 m.u. apart, and genes B and C are 20 m.u. apart. Which of the following linkage maps is most consistent with your results? A) A - B - C B) A - C - B C) B - C - A D) C - B - A E) C - A - B

C - A - B

Imagine an alternative history of life on our planet, where we all share a completely different universal triplet genetic code. (In other words, to answer the question you cannot just use a codon table.) You are helping Har Gobind Khorana to fill in the final gaps in the genetic code. Using repeating mRNA copolymers, you have found that: CG repeating di-nucleotide result in Trp-Arg-Trp-Arg... polypeptides. CCG repeating trinucleotides result in either Pro-Pro-Pro..., Trp-Trp-Trp..., or Phe-Phe-Phe... polypeptides. Based on these data, which codon can be assigned to Trp? A) Cannot be determined from these data. B) GCG C) CCG D) CGC E) GCC

CGC

Most cells in the human body do not express telomerase, but cancer cells frequently have mutations leading to high telomerase expression. What do you expect the effects of mutations increasing telomerase expression in cancer cells? A) Cancer cell DNA synthesis will halt. B) Cancer cell chromosomes will become shorter every cell division. C) Cancer cell DNA synthesis will become more error prone. D) Cancer cell chromosomes will not experience telomere shortening every cell division. E) Cancer cell mitosis will be arrested.

Cancer cell chromosomes will not experience telomere shortening every cell division

Which of the following was not a key experiment that led to our understanding of eukaryotic chromatin structure? A) Visualization of nucleosomes under an electron microscope. B) Nuclease digestion of nucleosomal DNA. C) Generation of X-ray crystal structures of histones bound to DNA. D) Characterization of chromatin structure in yeast mutants lacking histones. E) All of the answers include key experiments for understanding nucleosome structure.

Characterization of chromatin structure in yeast mutants lacking histones

The diagram below represents a eukaryotic gene, with the nucleotides above highlighting important features of the DNA. In which region would the insertion of a single base-pair into the DNA definitely cause a frameshift mutation? A) A B) B C) C D) D E) E

D

DNA replication poses several challenges to the cell that must be resolved for replication to A. the information for the production of bacteriophages (short "phages") is encoded in the proceed. All of the following are cellular solutions to the challenges posed by DNA replication except... A) Higher eukaryotes utilize multiple origins of replication to reduce the amount of time needed for DNA replication. B) Primase synthesizes an RNA primer since DNA polymerase can only extend an existing polynucleotide chain. C) DNA polymerase synthesizes DNA in the 3' -> 5' direction for continuous DNA synthesis on the lagging strand. D) Telomerase extends the ends of linear chromosomes to counteract chromosome shortening. E) Helicase unwinds to the DNA to allow the replication fork to form.

DNA polymerase synthesizes DNA in the 3' -> 5' direction for continuous DNA synthesis on the lagging strand

What would be the consequence if there was no negative supercoiling, but instead all of the DNA in the cell was positively supercoiled? A) DNA replication and RNA transcription would be much more energetically costly for the cell B) The cell would no longer be able to compact its DNA C) Eukaryotes could no longer use nucleosomes to compact their DNA. D) The cell would no longer require helicase. E) There would be no consequence.

DNA replication and RNA transcription would be much more energetically costly for the cell

What would be the consequence if there was no negative supercoiling, but instead all of the DNA in the cell was positively supercoiled? A) Eukaryotes could no longer use nucleosomes to compact their DNA. B) There would be no consequence. C) The cell would no longer require helicase. D) DNA replication and RNA transcription would be much more energetically costly for the cell. E) The cell would no longer be able to compact its DNA.

DNA replication and RNA transcription would be much more energetically costly for the cell

Which of the following statements about alleles is true? A) Two alleles of the same gene will be found at different locations on the same chromosome. B) Different alleles of the same gene will have one or more differences in DNA sequence. C) Two alleles of the same gene can be found on non-homologous chromosomes. D) After mitosis, the resulting daughter cells will always have different alleles. E) all of the above are true

Different alleles of the same gene will have one or more differences in DNA sequence

At the time of Tsuneko and Reiji Okazaki's discovery of both continuous and discontinuous DNA synthesis, scientists knew that DNA polymerase could only synthesize DNA 5' to 3'. Based on that piece of information, what was a plausible alternative model of DNA synthesis? A) Discontinuous DNA synthesis on both the leading and lagging strand. B) Continuous DNA synthesis on both the leading and lagging strand. C) Discontinuous DNA synthesis on the leading strand, and continuous DNA synthesis on the lagging strand. D) All of the above.

Discontinuous DNA synthesis on both the leading and lagging strand

The diagram below represents a eukaryotic gene, with the nucleotides above highlighting the important features of the DNA. In which region would a single base-pair substitution very likely change the length of the final mRNA? A) A B) B C) C D) D E) E

E

The following structure represents homologous chromosome pairing during meiosis. Which type of mutation can cause this type of structure to form? A) Inversion B) Translocation C) Duplication D) Deletion E) Either duplications or deletions

Either duplications or deletions

The following figure shows a simplified pathway for methionine biosynthesis in E. coli. If you generated a mutant defective in producing functional Enzyme 4, adding which compound to minimal medium would allow the auxotrophic mutant to grow? A) cysteine. B) cystathione. C) homocysteine. D) methionine E) Either homocysteine or methionine.

Either homocysteine or methionine

Assume traits b and c are inherited according to Mendelian principles when considered independently. Based on the results of your chi-square analysis in the above question (21), you should do which of the following: (A) Reject the null hypothesis and conclude that these genes are unlinked. (B) Reject the null hypothesis and conclude that each of these traits are controlled by more than two alleles. (C) Fail to reject the null hypothesis and conclude that these genes are linked. (D) Fail to reject the null hypothesis and conclude that these genes are unlinked. (E) Reject the null hypothesis and conclude that these genes are linked.

Fail to reject the null hypothesis and conclude that these genes are unlinked

You being a sly yeast geneticist have moved the ADE2 gene very close to a region of the genome that you suspect is heterochromatin, and you measure Ade2 enzyme activity in a culture (i.e. millions of yeast cells). (Note: the error denotes the standard deviation of 3 biological replicates). True or False: these data are consistent with the tested region being heterochromatin.

False

What is the universal biological definition of a "female" organism? A) Female organisms always have two X chromosomes. B) Females are the smaller of the two sexes. C) Females produce larger gametes compared with males. D) Females carry and bear live offspring. E) All of the above are true.

Females produce larger gametes compared with males

The following figures show two competing hypotheses concerning the origin of mutations, which were formally tested by Luria and Delbrück's fluctuation test. For each of the figures, wild-type cells are depicted in white, antibiotic resistant mutants are depicted in black, and treatment with biocide (phage in this case) is depicted by the horizontal bar. Which figure depicts the hypothesis that mutations arise randomly and not due to biocide exposure? A) Figure #1 B) Figure #2

Figure #1

Which of the following are not consistent with Erwin Chargaff's rules? A. A = T B. G = C C. A + G = C + T D. G + C = T + A

G + C = T + A

Student-sumitted question! In what phase of the cell cycle do cells neither grow nor divide? (A) S phase (B) Mitosis (C) G2 (D) G0 (E) G1

G0

An individual with the genotype GgWw can produce which of the following gamete types? A) GgWw only B) GW and gw only C) Gg and Ww only D) GG, Gg, gg, WW, Ww, and ww E) GW, Gw, gW, and gw

GW, Gw, gW, and gw

Consider the following scenario for questions 23-24 You are examining two traits in cucumbers. For flower color, the dominant allele (W) produces yellow flowers, and the recessive allele (w) produces white flowers. For fruit texture, the dominant allele (R) produces smooth cucumbers, and the recessive allele (r) produces rough cucumbers. You mate a dihybrid plant showing both dominant traits to plant showing both recessive traits. You obtain the following numbers of offspring: yellow, smooth 92 white, rough 93 yellow, rough 7 white, smooth 8 Based on the above information, what is most likely true concerning genes w and r? (A) Genes w and r are located closely on non-homologous chromosomes. (B) Genes w and r are located closely on the same chromosome. (C) Genes w and r are located on opposite ends of the same chromosome. (D) We can't infer anything about the physical relationship of these genes from this dataset. (E) Genes w and r are located on opposite ends of non-homologous chromosomes.

Genes w and r are located closely on the same chromosome

If a gene is considered haploinsufficient, this means that: (A) Heterozygotes carrying a wild-type allele and a loss-of-function allele have a mutant phenotype. (B) Homozygotes carrying two loss-of-function alleles have a mutant phenotype. (C) One half of the gene sequence is not necessary for wild-type function. (D) Heterozygotes carrying a wild-type allele and a gain-of-function allele have a mutant phenotype. (E) Haploids carrying a wild-type allele and a loss-of-function allele have a mutant phenotype.

Heterozygotes carrying a wild-type allele and a loss-of-function allele have a mutant phenotype

Fragile X syndrome is a caused by a dominant X-linked mutation that causes a variety of learning defects and cognitive impairments (assume that this allele is rare in the general population and fully penetrant in heterozygotes). If a female with Fragile X syndrome has a child with an unaffected male, which of the following should be true? A) All their male children should be affected, but none of their female children. B) All their female children should be affected, but none of their male children. C) All of their children should be affected, regardless of sex. D) Half of their children should be affected, regardless of sex. E) None of their children should be affected.

Half of their children should be affected, regardless of sex

When Mendel performed his experiments, he knew which of the following? (A) He didn't know any of these things. (B) Genes exist on chromosomes. (C) Meiosis creates haploid gametes. (D) Natural selection changes allele frequencies. (E) DNA is the genetic material.

He didn't know any of these things

Which of the following statements about chromosomes is true? (A) Human chromosomes exist in pairs. (B) Chromosomes consist of multiple DNA double-helix molecules. (C) Chromosomes are composed entirely of protein. (D) Genes make up the majority of human chromosomes. (E) Chromosomes were linked to heredity well before the work of Mendel.

Human chromosomes exist in pairs

Which of the following individuals must be a carrier for this genetic disease? A) IV-3 B) I-1 C) II-3 D) II-4 E) III-5

III-5

What is the effect of de-acetylation of histone tail lysine residues? A) It increases histone affinity for binding DNA. B) It increases histone affinity for other non-histone proteins. C) It helps activate transcription. D) It increases translational efficiency. E) It helps with RNA export out of the nucleus.

It increases histone affinity for binding DNA

Using new genetic engineering techniques, you are able to create a Drosophila zygote with four X chromosomes, two Y chromosomes, and four copies of each autosome. Assume this zygote survives and becomes an adult fly. Based on what you've learned about sex determination in Drosophila, what sexual phenotype should this fly display? (A) It should have both male and female genitals. (B) It should have female genitals. (C) It should have male genitals. (D) It should have no sexual characteristics. (E) There is a 50:50 chance that it will be male or female

It should have female genitals

Seymour Benzer found that co-infection of two different rII- A mutants or two different rII- B phage mutants gave rise to plaques at an extremely low frequency. What were the implications of this finding? A) It suggests that crossing-over can occur within a gene. B) It suggests that different mutant alleles of the same gene can complement each other. C) It suggests that intragenic suppression cannot occur. D) It suggests that back mutations are rare phenomena. E) It suggests that recombination occurs more often at mutational hotspots.

It suggests that crossing-over can occur within a gene.

Which protein is responsible for cleaving lactose into galactose and glucose monomers? A) LacZ B) LacY C) LacA D) LacI E) CRP

LacZ

If you were to compare intestinal cells between lactose-tolerant and lactose-intolerant individuals, what should you expect to observe? A) The lactase gene will be present in cells from the lactose-tolerant individual, and absent in cells from the lactose-intolerant individual. B) Cells from the lactose-tolerant individual will be diploid, and cells from the lactose-intolerant individual will be haploid. C) Lactase mRNA will be present in cells from the lactose-tolerant individual, and absent in cells from the lactose-intolerant individual D) Cells from the lactose-intolerant individual will exhibit a sickle-cell phenotype, and cells from the lactose-tolerant individual will look wild type. E) A mutant lactase protein will be present in the lactose-intolerant individual

Lactase mRNA will be present in cells from the lactose-tolerant individual, and absent in cells from the lactose-intolerant individual

Which of the following is false concerning DNA electrophoresis? A) It uses an agarose gel matrix to separate DNA molecules according to size. B) Negatively charged DNA migrates toward the positive electrode. C) Larger DNA fragments migrate faster through the gel matrix. D) DNA bands are generally visualized using fluorescent dyes that bind DNA. E) None of the answers are false.

Larger DNA fragments migrate faster through the gel matrix

Regarding the figure in the question above, what is the difference between the observed results for lanes 1 (low DNase amount) and 2 (medium DNase amount)? A) Low levels of DNase digest the histone H1 protein, while medium levels digest the core histone octamer proteins. B) Low levels of DNase digest between every nucleosome, while medium levels completely digest the linker DNA. C) Low levels of DNase digest occasionally to leave multiple nucleosomes intact, while medium levels digest the DNA between every nucleosome. D) Low levels of DNase digest the linker DNA, while medium levels digest the nucleosome core DNA. E) Low levels of DNase digest the DNA between every nucleosome, while medium levels of DNase digest occasionally to leave multiple nucleosomes intact.

Low levels of DNase digest occasionally to leave multiple nucleosomes intact, while medium levels digest the DNA between every nucleosome

What is the biological definition of a "male" organism? (A) Males produce smaller gametes compared with females. (B) Males are the more visually striking of the two sexes. (C) There is no biological definition of a male organism. (D) Male organisms always have a Y chromosome. (E) Males are the larger of the two sexes.

Males produce smaller gametes compared with females

Regarding the figure in the question above, what is the difference between the observed results for lanes 2 (medium DNase amount) and 3 (high DNase amount)? (A) Medium levels of DNase digest between every nucleosome, while high levels completely digest the linker DNA. (B) Medium levels of DNase digest occasionally to leave multiple nucleosomes intact, while high digest the DNA between every nucleosome. (C) Medium levels of DNase digest occasionally to leave multiple nucleosomes intact, while high digest the linker DNA. (D) Medium levels of DNase digest the linker DNA, while high levels digest the nucleosome core DNA. (E) Medium levels of DNase digest the histone H1 protein, while high levels digest the core histone octamer proteins.

Medium levels of DNase digest between every nucleosome, while high levels completely digest the linker DNA

Genetically identical agouti mice, when fed low or high levels of folate in their diet, show remarkably different phenotypes. What is the molecular basis for the phenotypic differences? A) Mice with the pseudo-agouti phenotype inherit a repressor protein for the agouti gene. B) Mice with the pseudo-agouti phenotype inherit an activator protein for the agouti gene. C) Mice with the pseudo-agouti phenotype inherit extra folate biosynthetic genes. D) Mice with the pseudo-agouti phenotype inherit an agouti gene with high levels of promoter methylation. E) Mice with the pseudo-agouti phenotype inherit an agouti gene with high levels of unacetylated histones.

Mice with the pseudo-agouti phenotype inherit an agouti gene with high levels of promoter methylation

Which of the following is not an example of a cis element? A) lac operator B) GAL upstream activating sequence (UAS) C) CRP/CAP DNA-binding sequence D) a silencer E) Mig1

Mig1

Males bees are haploid. Because of this, they use ________ to produce gametes: (A) Aneuploidy (B) Mitosis (C) Meiosis (D) X-chromosome inactivation (E) Fertilization

Mitosis

About 2% of all people have inversions that are noticeable by karyotype, yet the vast majority are of no phenotypic consequence. Why is this the case? (A) The looping structure of inversions protect the DNA from mutation. (B) Actually, most inversions do cause noticeable phenotypic effects. (C) Inversions cannot get passed down to offspring. (D) Most inversions disrupt a gene, but most genes tolerate being disrupted. (E) Most inversions do not disrupt a gene.

Most inversions do not disrupt a gene

Which of the following are untrue regarding Down syndrome? A) It is most often caused by meiotic non-disjunction in the developing egg. B) It is an example of chromosomal aneuploidly. C) It can be caused by Robertsonian translocation. D) All of the above are untrue. E) None of the above are untrue.

None of the above are untrue

Which of the following is not a molecular solution to one of the cellular challenges posed by DNA replication? A) Okazaki fragments are produced for discontinuous DNA synthesis on both the leading and lagging strand. B) Eukaryotes use multiple origins of replication to reduce the time needed to replicate the genome. C) Telomerase ensures the linear chromosomes do not get progressively shorter after each replication cycle. D) Helicase unwinds the DNA double helix to facilitate formation of the replication fork. E) Ligase closes remaining open phosphodiester bonds

Okazaki fragments are produced for discontinuous DNA synthesis on both the leading and lagging strand

In the above question (26), which of the following could be the genotype of an offspring from one of the "parental" classes? A) qr / qr B) Qr / QR C) QR / qr D) Qr / qr E) qR / qR

Qr / qr

Meselson and Stahl used the heavy nitrogen isotope 15N to test the prevailing models of DNA replication. They allowed bacteria with 15N-labeled DNA to replicate their DNA twice in medium containing exclusively 14N ("light") nitrogen sources. They then used equilibrium density gradient centrifugation on DNA extracted after both the first and second replication cycles. (Reminder: heavy 15N = high density, light 14N = low density). If DNA replication was dispersive, what would you expect for the second replication cycle? (A) Two bands, one of low density and one of intermediate density. (B) Two bands, one of high density and one of intermediate density. (C) One band of high density. (D) One band of intermediate-to-low density. (E) Three bands, one of low density, one of intermediate, and one of high density.

One band of intermediate-to-low density

Which of the following inversions would very likely alter phenotype via affecting an essential gene's function or expression? A) The inversion repositions the gene into a euchromatic region. B) The inversion repositions the gene into a heterochromatic region. C) The inversion breakpoint happens in the middle of the gene. D) All the above are likely to alter the gene's function or expression. E) Only "B" and "C" are likely to alter the gene's function or expression.

Only "B" and "C" are likely to alter the gene's function or expression

You are isolating mutations in sweA, the first gene in the swe operon. One mutant had an interesting phenotype—it produced smaller levels of detectable SweA protein than in the wildtype strain. Which of the following mutations are likely to give you this result? A) Mutation in the sweA promoter. B) Mutation in the sweA Shine-Dalgarno sequence. C) A missence mutation in the sweA open reading frame. D) All of the above. E) Only A and B.

Only A and B

Which of the following is false concerning the differences between DNA and RNA? A) DNA contains thymine, while RNA contains uracil. B) RNA is a polar molecule, while DNA is non-polar. C) DNA contains 2-deoxyribose, while RNA contains ribose. D) DNA is generally double stranded, while RNA is generally single stranded. E) None of those statements are false.

RNA is a polar molecule, while DNA is non-polar

Hemophilia A is a human blood disorder caused by a recessive X-linked allele. Which of the following pedigrees is most consistent with the inheritance of Hemophilia A? A) Pedigree A B) Pedigree B C) Pedigree C D) Pedigree D E) None of these pedigrees are consistent with a recessive X-linked condition.

Pedigree D

Before the 1940's, many scientists hypothesized that protein was more likely to be the genetic material than DNA. What best contributed to the logic of this hypothesis? A) Pheobus Levene's contention that the 4 bases of DNA repeated in the same order. B) The finding that the nucleus was phosphorus rich, and that proteins are the major phosphorus containing biomolecule. C) The chemical instability of DNA was though to be too high for it to reliably store genetic information. D) The spontaneous chemical instability of amino acids could explain known mutation rates. E) The finding that genes were partially made up of protein.

Pheobus Levene's contention that the 4 bases of DNA repeated in the same order

The process of gene expression involves which of the following? A) Transporting DNA from the nucleus to the cytoplasm B) Inducing a mutation to produce a loss of function allele C) Translating a protein sequence into RNA D) Splicing frog DNA to fill in gaps in the genetic code E) Producing a functional RNA via transcription

Producing a functional RNA via transcription

Either strand of the double helix can serve as a template for transcription. How does the cell determine which strand to use for any given gene? A) Promoters determine which strand RNA polymerase binds to. B) Start codons determine which strand RNA polymerase binds to. C) Stop codons determine which strand RNA polymerase binds to. D) The Shine-Dalgarno sequence determines which strand RNA polymerase binds to. E) Actually, the cell cannot distinguish and randomly chooses.

Promoters determine which strand RNA polymerase binds to

For Barbara McClintock's Ac/Ds system, let's assume the Ds element is currently inserted into the c gene, leading to the white (mutant) kernel phenotype. What is the expected phenotype for the kernels if you deleted only the inverted repeat sequences of the Ac element? (A) All kernels would revert to completely purple. (B) Purple spots would randomly appear on the kernels. (C) The kernels would fail to develop fully. (D) White spots would randomly appear on the kernels. (E) All kernels would remain white.

Purple spots would randomly appear on the kernels

Perform a chi-square analysis on this dataset. Based on your results you should: A) Reject the null hypothesis and conclude these genes are unlinked. B) Reject the null hypothesis and conclude these genes are linked. C) Fail to reject the null hypothesis and conclude these genes are unlinked. D) Fail to reject the null hypothesis and conclude these genes are linked. E) Fail to reject the null hypothesis and conclude these genes are epistatic.

Reject the null hypothesis and conclude these genes are linked

If mutations were specifically induced as a direct response to selective pressure, what would have been the result of Esther and Joshua Lederberg's replica printing experiment? (Reminder: the experimental design was to isolate colonies on a plate grown without antibiotic, and then replica print to multiple plates with antibiotic). A) Resistant colonies would always arise in the exact same location on each of the different antibiotic plates. B) Resistant colonies would never appear on any of the different antibiotic plates. C) The number of resistant colonies on each of the different antibiotic plates would greatly fluctuate. D) Resistant colonies would appear to be randomly distributed across the different antibiotic plates. E) Every single colony from the plate grown without antibiotic would also grow on each of the different antibiotic plates.

Resistant colonies would appear to be randomly distributed across the different antibiotic plates

Based on the information in the above question (33), assume a brown-haired hog and a white-haired hog produce multiple litters of offspring with brown or red hair (never white). Which of the following are likely genotypes for the parents? A) RR; Ee and Rr; ee B) Rr; Ee and Rr; Ee C) RR; EE and Rr; ee D) Rr; EE and rr; ee E) None of these are likely genotypes.

Rr; EE and rr; ee

Wild-type humans have sweat glands distributed across most of their skin. Anhidrotic ectodermal dysplasia is a recessive X-linked condition caused by a loss-of-function allele of the EDA gene. Males affected by this condition have no sweat glands. What phenotype should an XX female display if she is heterozygous for this loss-of-function EDA allele? A) She should have no sweat glands. B) She should have a normal number of sweat glands. C) She should show a mosaic phenotype, with some patches of skin with sweat glands and some patches of skin without. D) She should have a 50:50 chance of having no sweat glands or normal sweat glands. E) She should have twice as many sweat glands as normal, because genes on the X chromosome are more highly expressed in females.

She should show a mosaic phenotype, with some patches of skin with sweat glands and some patches of skin without

Which of the following disorders would not be diagnosed during karyotype analysis? A) Cris-du-chat syndrome B) Down syndrome C) Turner syndrome D) Klinefelter syndrome E) Sickle-cell anemia

Sickle-cell anemia

What is a plausible explanation for the fact that trisomy 21 is the only human aneuploidy with survival past infancy? (A) Smaller chromosomes decrease the likelihood that gene dosage imbalance will be lethal. (B) Smaller chromosomes that are aneuploid segregate more efficiently during mitosis. (C) Smaller chromosomes with an aneuploidy can more easily be lost to restore euploidy. (D) Smaller chromosomes can be inactivated to compensate for aneuploidy. (E) Smaller chromosomes with an aneuploidy can be digested by nucleases to restore euploidy.

Smaller chromosomes decrease the likelihood that gene dosage imbalance will be lethal

A geneticist found that a particular mutation had no effect on the function of an enzyme. This mutation most likely involved ... A) Substitution of one nucleotide within the open reading frame. B) Deletion of the entire gene. C) An insertion of one nucleotide in the open reading frame. D) An alteration of the start codon. E) An alteration of the stop codon.

Substitution of one nucleotide within the open reading frame

Oswald Avery and his colleagues used several different treatments to understand the nature of Fred Griffith's "transforming principle." Based on their results, what is the most likely explanation for the transformation of avirulent R strain bacteria into virulent S strain bacteria? A) The R strain bacteria coated themselves with S strain lipids. B) The R strain bacteria coated themselves with S strain polysaccharide. C) The R strain bacteria took up S strain virulence proteins. D) The R strain bacteria took up S strain RNA containing virulence genes. E) The R strain bacteria took up S strain DNA containing virulence genes.

The R strain bacteria took up S strain DNA containing virulence genes

Your friend Brian has a new cologne called Sex Panther, and he wants you to test it for mutagenicity using the Ames Test. (For the sake of the question, assume that the compound in question absorbed into the body and metabolized like any other drug). You obtain the following results: SAMPLE: #His+ Relavent Colonies: - saline --> 5 - rate liver enzyme in saline --> 7 - cologne in saline --> 6 - cologne plus rat liver enzymes in saline --> 138 What conclusion is most consistent with this data? A) The cologne is mutagenic, but it is metabolized into non-mutagenic metabolites. B) Both the cologne and its metabolites are mutagenic. C) The cologne is not mutagenic, but it is metabolized into mutagenic metabolites. D) The cologne increases the mutagenic activity of rat liver enzymes. E) 60% of the time, it causes mutations all of the time.

The cologne is not mutagenic, but it is metabolized into mutagenic metabolites

Why are large chromosomal deletions often lethal, even in heterozygotes? A) The deletion often spans one or more essential genes. B) The cell is unable to repair double stranded breaks that span a large area. C) Large deletions cause the chromosome to condense into heterochromatin. D) Because the deletion chromosome cannot pair with its homolog during mitosis. E) Actually, large deletions are rarely lethal.

The deletion often spans one or more essential genes

Which of the following is most directly responsible for Mendel's Fourth Postulate of Independent Assortment? (A) The fact that the genes he was studying were haplosufficient (B) Mutations caused by errors during DNA replication (C) Random matching of sperm and egg during fertilization (D) Swapping of alleles during crossing over (E) The fact that genes can be located on different chromosomes

The fact that genes can be located on different chromosomes

When studying proflavin-induced mutants, Crick and colleagues observed that combining 3 single base-pair deletions or 3 single base-pair insertions restored the phage to Wild Type. However, wild-type phage were only recovered if the 3 deletions or insertions mapped very close together. What is the most likely explanation for this observation? A) Proflavin induced mutations naturally cluster next to each other. B) Proflavin induced mutations always occur in threes. C) Cellular repair machinery prevents insertions or deletions from occurring at great distances. D) Recombination reduces the distance between insertions or deletions. E) The further the mutations are separated from each other, the more of the open reading frame remains frameshifted.

The further the mutations are separated from each other, the more of the open reading frame remains frameshifted

Which of the following would you expect to find on a region of the genome that is facultative heterochromatin? A) The gene ACT1 encoding actin - an essential cytoskeletal component expressed in all cell types in the body. B) The gene HBE1 encoding hemoglobin epsilon - expressed only in the red blood cells during embryo development. C) Centromeric DNA. D) Telomeric DNA. E) All of the answers include regions that you would expect to be facultative heterochromatin.

The gene HBE1 encoding hemoglobin epsilon - expressed only in the red blood cells during embryo development

Before the discovery of the actual genetic material in all organisms, what was a known property that the genetic material must possess? A. The genetic material must be a type of nucleic acid B. The genetic material must be present in two copies C. The genetic material must be heritable D. The genetic material must be perfectly stable E. None of these answers are required properties for the genetic material

The genetic material must be heritable

Which of the following is a required property for the genetic material of any organism? A) The genetic material must contain exactly four nucleotides to reliably express genetic information. B) The genetic material must be heritable. C) The genetic material must consist of DNA. D) The genetic material must be replicated with perfectly fidelity. E) The genetic material must consist of protein.

The genetic material must be heritable

You have identified a lac mutant that consumes both lactose and glucose at the same time. Which of the following statements about the mutant cannot be true. A) The mutant is defective in catabolite repression. B) The mutation might cause the cAMP-receptor protein (CRP or CAP) to activate transcription even in the absence of cAMP. C) The mutation might cause adenylate cyclase to generate high cAMP levels even when glucose is present. D) The mutant is able to grow on lactose as the sole source of carbon and energy. E) The mutation is a deletion of lacI.

The mutation is a deletion of lacI

Why are histone proteins rich in arginine and lysine amino acids? A) The positive charge of these residues is important for interacting with the DNA. B) The negative charge of these residues is important for interacting with chromatin. C) The positive charge of these residues is important for non-histone protein interactions. D) The negative charge of these residues is important for nucleosome positioning. E) None of the above.

The positive charge of these residues is important for interacting with the DNA

Imagine an alternative universe where the Crick proflavin-induced mutagenesis experiments were performed. Imagine following results were obtained when analyzing T4 phage frame-shift mutations ('+' = single base insertion and '-' = single base deletion): Based on your codon-length assumptions, what can you say about proteins in this alternative universe? A) The proteins would not have any primary structure B) The proteins would potentially be no different from our proteins C) The proteins would have up to 15 amino acids instead of 20 D) The proteins would have up to 255 different amino acids instead of 20

The proteins would have up to 15 amino acids instead of 20

Student-submitted question! Which of the following best explains why fruit flies with 2X:2A and 3X:3A genotypes both develop as female? (A) In both cases, all but one X chromosome are turned into Barr bodies (B) The ratio of X chromosomes to sets of autosomes is 1 in both cases (C) None of these (D) The absence of a Y chromosome confers femaleness (E) The ratio of X chromosomes to sets of autosomes is 0.5 in both cases

The ratio of X chromosomes to sets of autosomes is 1 in both cases

You are a zebrafish geneticist, and you have two true-breeding strains of fish with the same mutant phenotype: they are completely missing their pectoral fins. You cross these two strains together, and all of the resulting offspring have wild-type pectoral fins! What should you conclude from this miraculous result? A) There is a third gene that is epistatic to both of these genes. B) The same mutant phenotype can be caused by mutations in two different genes. C) The two true-breeding lines have mutations in the same gene. D) The two true-breeding lines are heterozygous for two different genes. E) This phenotype is due to environmental, not genetic, causes.

The same mutant phenotype can be caused by mutations in two different genese

All of the following were part of Watson and Crick's model of DNA structure except... A) The double helix is held together by hydrogen bonds between complementary nucleotides. B) Each DNA strand is polar, consisting of unique 5' and 3' ends. C.) The two DNA strands assume a twisted helical structure. D.) The sugar-phosphates of the nucleotides make up the outside "backbone" DNA. E) The two DNA strands are parallel with identical nucleotide sequences.

The two DNA strands are parallel with identical nucleotide sequences

Which of the following are features of the double helix model of DNA proposed by Watson and Crick? A. The DNA consists of a single polynucleotide strand that folds onto itself to form a double helix. B. Two polynucleotide strands are bound together by specific hydrogen bonding between the sugar-phosphate backbone. C. The sugar-phosphate backbone of the two polynucleotide strands are on the inside and the paired bases on the outside. D. The two polynucleotide strands are anti-parallel with complementary nucleotide sequences. E. The sugar-phosphate backbone contains 5' to 5' phosphodiester linkages.

The two polynucleotide strands are anti-parallel with complementary nucleotide sequences

In their historic paper describing the structure of DNA, Watson and Crick wrote: "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material." Which feature of the two DNA strands suggests a possible copying mechanism? A) The two DNA strands are antiparallel (5' end of one strand is where 3' end of the other strand is). B) Separation of the two strands requires very little energy. C) The two strands have complementary sequences, with one strand determining the nucleotide sequence of the other strand. D) The two strands have identical sequences. E) The two strands have identical sequences, except one is reversed with respect to the other.

The two strands have complementary sequences, with one strand determining the nucleotide sequence of the other strand

Which of the following is true regarding histones? A) Their positively charged amino acid residues are important for interacting with the negatively charged DNA backbone. B) They are weakly conserved across eukaryotes. C) They can be seen under the electron microscope as aggregates with extremely variable linker lengths. D) They play an essential role in compacting bacterial chromosomes. E) The linker histone H1 is a key nucleosomal histone.

Their positively charged amino acid residues are important for interacting with the negatively charged DNA backbone

Which of the following are false of mutations in somatic cells? A) They are not heritable. B) They can affect the phenotype of individuals who carry them. C) They do not occur in gametes. D) They are highly relevant to evolution through being subjected to natural selection. E) All of the answers are false.

They are highly relevant to evolution through being subjected to natural selection

Which of the following statements about mutations is false? A) They are much more common than would be expected based on the frequency of DNA "lesion" formation. B) Beneficial mutations are rare compared to neutral and deleterious mutations. C) They generally occur spontaneously at low frequencies. D) They occur randomly and not as a directed response to environmental change. E) Mutagens can increase the frequency of mutations.

They are much more common than would be expected based on the frequency of DNA "lesion" formation

Which of the following concerning gene deletions is false? A) They are not usually visualizable through karyotype analysis. B) Cris-du-chat syndrome is an example of a medically relevant human deletion. C) They often have severe phenotypic consequences, including lethality. D) They can be caused by chromosomal breaks due to ionizing radiation. E) They can be caused by unequal crossing over during meiosis.

They are not usually visualizable through karyotype analysis

Which of the following is not true of chromosomal duplications? (A) They form visible loops during mitosis and meiosis. (B) They can be caused by unequal crossing-over. (C) They play an important role in the evolution of paralogs. (D) They can be caused by X-ray radiation. (E) They are usually lethal when homozygous.

They are usually lethal when homozygous

Which of the following are true of mutations in somatic cells? A) They can be passed on to offspring. B) They may contribute to cancer. C) They are always harmful. D) They occur in DNA of the gametes. E) All of the answers are true.

They may contribute to cancer

Which of the following concerning gene deletions is false? A) They can be caused by chromosomal breaks due to ionizing radiation. B) They can be caused by unequal crossing over due to homologous chromosome misalignment at similar/repetitive DNA sequences. C) They often have no phenotypic consequence in homozygotes. D) They produce characteristic chromosome loops that are visible during mitosis/meiosis. E) Cris-du-chat syndrome is an example of medically relevant human deletion.

They often have no phenotypic consequence in homozygotes

Which of the following concerning gene duplications is true? A) They produce characteristic chromosome loops that are easily cytologically distinguishable from deletion loops. B) They provide a potential source of raw genetic material for the evolution of paralogs. C) They are only caused chromosomal breaks due to ionizing radiation. D) They almost always cause severe phenotypic effects due to increased gene dosage. E) They are only caused by unequal crossing over.

They provide a potential source of raw genetic material for the evolution of paralogs.

Meselson and Stahl used the heavy nitrogen isotope 15N to test the prevailing models of DNA replication. They allowed bacteria with 15N-labeled DNA to replicate their DNA twice in medium containing exclusively 14N ("light") nitrogen sources. They then used equilibrium density gradient centrifugation on DNA extracted after both the first and second replication cycles. (Reminder: heavy 15N = high density, light 14N = low density). If DNA replication was conservative, what would you expect for the first replication cycle? A) Three bands, one of low density, one of intermediate, and one of high density. B) Two bands, one of intermediate density and one of low density. C) One band of low density. D) Two bands, one of high density and one of low density. E) One band intermediate density.

Two bands, one of high density and one of low density

What amino acid is encoded by the fourth codon of the following coding sequence? ATGCCTACGTATGAG (A) Met (B) Tyr (C) Pro (D) Thr (E) Trp

Tyr

If Fred Griffith's "transforming principle" were the polysaccharide capsule itself instead of DNA, which treatment of purified transforming principle would eliminate bacterial transformation? A) Protease B) DNase C) RNase D) Ultracentrifugation

Ultracentrifugation

All of the following are general properties of DNA polymerases except... A) Require a "primer" to initiate DNA synthesis. B) Use single-stranded DNA as a template. C) DNA synthesis occurs in the 5' to 3' direction. D) Use ATP as substrate to close remaining open phosphodiester bonds. E) Use nucleoside triphosphates as substrate for DNA polymerization.

Use nucleoside triphosphates as substrate for DNA polymerization

What genetic phenomenon explains the following paradox: There are 64 possible codons, but only 30 to 40 different tRNA types? A) Non-overlapping genetic code. B) Comma-less code. C) Unambiguous genetic code. D) Non-redundancy. E) Wobble.

Wobble

Imagine an alternative history of life on our planet, where we all share a completely different universal triplet genetic code. (In other words, to answer the question you cannot just use a codon table.) You are helping Leder and Nirenberg with their triplet binding experiment. You just tested the GUC triplet with every possible radiolabeled amino acid, and you never observe radioactivity on the filter. How do you interpret this result? A) You conclude that GUC may code for multiple different amino acids. B) You conclude that GUC may be a stop codon. C) You conclude that GUC definitely codes for valine. D) You conclude that genetic code must be a doublet.

You conclude that GUC may be a stop codon

The swe operon contains a three-gene operon (sweABC) with all of the genes necessary to break down the common (albeit fictional) sugar, sweetose. Right next to the swe operon, you have identified a gene named sweR. You hypothesize that SweR is a regulatory protein. To test this, you generate deletions in sweR, and find that these deletion mutants are unable to grow on sweetose, and the operon is constitutively "off." Based on this observation, SweR is likely which type of regulatory protein? A) repressor B) activator C) promoter D) operator E) none of the above

activator

Which of the following is not true about genes? A) genes are located on chromosomes B) genes control traits C) genes are found in the nuclei of eukaryotic cells D) all genes encode mRNAs, which are translated into protein E) the function of a gene is determined by its nucleotide sequence

all genes encode mRNAs, which are translated into protein

Fragile X Syndrome is an X-linked dominant trait. A father with Fragile X syndrome should expect to pass this trait on to: (A) all of his sons and none of his daughters. (B) none of his children (C) all of his daughters and none of his sons. (D) 50% of his daughters and none of his sons. (E) all of his children, regardless of sex.

all of his daughters and none of his sons

Fruit flies with one functional copy of the white gene and one broken copy exhibit a wild-type level of red eye pigment. This means that: A) the wild type allele is dominant over the loss of function allele B) the white gene is haplosufficient C) heterozygous flies are indistinguishable from homozygous wild-type flies D) the white-eye phenotype is recessive E) all of the above

all of the above

A transcription factor: (A) can activate or repress many different genes. (B) is a protein that binds to DNA sequences and alters gene transcription. (C) is a protein that acts as a molecular on/off switch for specific genes. (D) All of the above are true (E) None of the above are true

all of the above are true

Which of the following phenomena demonstrate that Beadle and Tatum "one gene-one enzyme hypothesis" is an oversimplification? A) unambiguous genetic code B) degenerate genetic code C) transcriptional coupling D) Wobble E) alternative splicing

alternative splicing

Two homologous chromosomes in a diploid cell: (A) will pair with each other (synapse) during mitosis. (B) are always identical in DNA sequence. (C) each carry different genes (D) are the same length and have the same centromere position. (E) All of these statements are true.

are the same length and have the same centromere position

This pedigree is most consistent with which of the following patterns of inheritance? A) Autosomal recessive B) X-linked recessive C) Autosomal dominant D) X-linked dominant E) This trait must be inherited in a non-Mendelian fashion.

autosomal recessive

The following Punnett square shows the F2 offspring from one of Mendel's dihybrid crosses. Which of the following accurately describes the phenotype of an organism from the starred box? AD Ad aD ad x AD Ad aD ad What will be the 3rd box in the last column? (A) axial, dwarf (B) axial, terminal (C) axial, tall (D) terminal, dwarf (E) terminal, tall

axial; tall

Why does the Barbara McClintock's Ds element require Ac to be present in order to mobilize? A) because Ds is a DNA only transposon, while Ac is a retrotransposon. B) because Ds does not contain its own inverted repeats. C) because Ds lost its mojo. D) because Ds is a retrotransposon, while Ac is a DNA only transposon. E) because Ds lacks a functional transposase enzyme.

because Ds lacks a functional transposase enzyme

You have isolated a mutant with a deletion in lacI. What is the expected phenotype? A) unable to grow on lactose B) able to grow on lactose C) lac operon is constitutively ON D) lac operon is constitutively OFF E) both B and C

both B and C

The secondary structure of a protein . . . A) can include α-helices and β-sheets. B) refers to the amino acid sequence of a protein. C) is the three-dimensional shape of a protein. D) refers to the oligomeric state of a protein. E) none of the above.

can include α-helices and β-sheets

Mutations are rare because ... A) cells have machinery to prevent and repair DNA damage that would otherwise lead to mutations. B) they only occur in adaptation to changing environmental conditions. C) they only arise due to mutagens, which are rare in the environment. D) DNA polymerase actively introduces mutations at a tightly controlled rate. E) the spontaneous rate of DNA "lesion" formation is extremely low.

cells have machinery to prevent and repair DNA damage that would otherwise lead to mutations

The wild-type allele of gene Z encodes antigen ZA, which is expressed on the surface of liver cells. A mutant allele of the Z gene encodes antigen ZB, which has a slightly different amino-acid sequence, but is still present at the cell surface. Based on your understanding of gene products, you should expect the wild-type allele to be ______ the ZB allele. A) completely dominant to B) completely recessive to C) codominant with D) recessively epistatic to E) dominantly epistatic to

codominant with

Which of the following is a reasonable way (i.e., one of the ways we learned) of describing a diploid organism that is heterozygous for recessive alleles of three genes located on the same chromosome? (A) g h i + + + (B) + / g ; h i / + + (C) g g / h h / i i (D) g + i / + h + (E) g / + ; h / + ; i / +

g + i / + h +

Genes are least likely to be found in which type of chromatin? A) euchromatin B) facultative heterochromatin C) constitutive heterochromatin D) variegated chromatin E) Barr bodies

constitutive heterochromatin

The following figure shows a simplified pathway for methionine biosynthesis in E. coli. If you generated a mutant defective in producing functional Enzyme 4, which compound would you expect to accumulate inside of the cells? A) cystathione B) cysteine C) both homocysteine and methionine D) homocysteine E) methionine

cystathione

For a pair of alleles that behave in a Mendelian fashion, the phenotype of the _______ allele will be visible in a heterozygote. (A) dominant (B) loss-of-function (C) haplosufficient (D) recessive (E) gain-of-function

dominant

Which of the following is not required when performing Nirenberg and Leder's triplet binding assay? A) a small mRNA triplet. B) radiolabeled "test" amino acids. C) filter paper with very large pores so that ribosomes are able to pass through. D) E. coli cell-free extract containing ribosomes. E) All of the answers include something that is required.

filter paper with very large pores so that ribosomes are able to pass through

Which of the following would be a reasonable and accurate way of describing an individual that is dihybrid for recessive alleles at two linked genes, g and h? A) g + / + h B) g h + + C) g / + ; h / + D) + / g ; h /+ E) g g / h h

g + / + h

You have isolated 2 new rII - T4 phage mutants and wish to determine whether they are located in either the rII A gene or rII B gene. Fortunately, you have previously characterized a mutant with a mutation in the rII A gene (Mutant A1). You performed complementation analysis by co-infecting mutant A1 with either Mutant 2 or Mutant 3. The results are shown below. Note that lysis only occurs if wild-type rII + phage are recovered from co-infection. Which genes are mutated in Mutants 2 and 3, respectively? A) gene B, gene A B) gene A, gene B C) gene C, gene C D) gene B, gene B E) gene A, gene A

gene A, gene B

Unlike most animals, male bees produce sperm using mitosis, not meiosis. This is because male bees are _______ organisms. A) heterogametic B) homogametic C) diploid D) haploid E) trisomic

haploid

Genes in which wild-type alleles show incomplete (partial) dominance over loss-of-function alleles are defined as _________. A) Haploinsufficient B) haplosufficient C) hemizygous D) heterologous E) co-dominant

haploinsufficient

Based on what you know about X chromosome inactivation in humans, you should conclude that all genes on the human X chromosome are _____. A) isogamous B) anisogamous C) haplosufficient D) haploinsufficient E) homogametic

haplosufficient

Unequal crossing-over is more likely to occur at ... A) highly similar sequences. B) highly dissimilar sequences. C) euchromatin. D) random sequences. E) genes.

highly similar sequences

A diploid individual that carries two identical alleles of the same gene is _______ , while an individual that carries two different alleles of the same gene is _______ . A) male; female B) wild type; mutant C) homozygous; heterozygous D) haplosufficient; haploinsufficient E) dominant; recessive

homozygous; heterozygous

You have isolated a mutation in a promoter that leads to increased expression of a gene. This is an example of which type of mutation? A. hypermorphic B. hypomorphic C. haplosufficient D. null E. loss-of-function

hypermorphic

In snapdragons, plants that are homozygous for the R1 allele have red flowers, plants that are homozygous for the R2 allele have white flowers, and R1/R2 heterozygotes have pink flowers. You cross two pink plants together and you obtain the following progeny: 13 red plants 22 pink plants 9 white plants The inheritance of this trait is most consistent with: A) recessive epistasis B) haplosufficiency C) complete (simple) dominance D) incomplete (partial) dominance E) codominance

incomplete (partial) dominance

Using new genetic engineering techniques, you are able to create a Drosophila zygote with four X chromosomes, four Y chromosomes, and four copies of each autosome. Based on what you know about Drosophila sex determination, what sexual phenotype should this fly display? A) It should have both male and female genitals. B) It should have female genitals. C) It should have male genitals. D) It should have no sexual characteristics. E) There is a 50:50 chance that it will be male or female.

it should have female genitals

You are studying two genes in grapes: one that controls fruit color (purple versus green) and one that controls fruit size (small versus large). You generate a dihybrid plant that produces small purple fruit, and you perform a testcross. In your testcross progeny, you observe the following phenotypic classes: small, purple: 55 large, green: 59 large, purple: 191 small, green: 195 In the above scenario, which phenotypes are recessive? A) small and purple B) large and green C) large and purple D) small and green E) It is impossible to conclude which are recessive based on this information.

large and green

Which of the following would you expect to be the least disruptive amino acid substitution in regard to protein function? A) arginine to aspartic acid B) tryptophan to glycine C) histidine to glutamic acid D) lysine to arginine E) lysine to glutamic acid

lysine to arginine

Which of the following is true about mitosis and meiosis? A) mitosis produces two diploid daughter cells, but meiosis does not B) crossing over occurs during mitosis, but not during meiosis C) sister chromatids separate during mitosis, but not during meiosis D) DNA replication occurs before mitosis, but not before meiosis E) mitosis reduces the chromosome number to haploid, but meiosis does not

mitosis produces two diploid daughter cells, but meiosis does not

Mutations in the gene encoding isocitrate dehydrogenase (IDH) are associated with several different types of cancers. Wild-type IDH converts isocitrate to alpha-ketoglutarate + CO2, while the mutant IDH instead produces 2-hydroxyglutarate (an "oncometabolite" that promotes cancer progression). This is what type of mutation? A) null B) hypomorphic C) hypermorphic D) neomorphic E) dominant negative

neomorphic

What are the consequences of having a balanced heterozygous translocation? A) severe phenotypic defects including sometimes lethality. B) no effects of either phenotype or reproduction. C) no effects of phenotype, but results in semi-sterility. D) suppression of recombination during meiosis. E) higher frequency of cancer.

no effects of phenotype, but results in semi-sterility

Which of the following occurs during metaphase of mitosis? A) the cell's DNA is replicated B) chromatin condenses into distinct chromosomes C) crossing over occurs between non-sister chromatids D) tetrads form and align near the middle of the cell E) none of the above

none of the above

What are the basic building blocks of DNA? A) legos B) nucleotides C) histones D) nucleosomes E) phosphodiesters

nucleotides

If a gene is haplosufficient, this means that: A) one functional copy is sufficient to produce a wild-type phenotype B) a loss-of-function allele will likely be dominant over the wild-type allele C) this gene is expressed at a higher level than normal D) there is a copy present on each of our 23 chromosomes E) a mutation has removed one half of the gene

one functional copy is sufficient to produce a wild-type phenotype

In the famous Hershey-Chase experiment, bacteriophage (phage for short) containing either radioactive sulfur (35S) or phosphorus (32P) were used to determine whether DNA or protein was the genetic material of phage. For this experiment's actual results, where was 35S detected? A) Infected E. coli cells and the phage that emerged from infected cells. B) Phage ghosts and infected E. coli cells. C) Phage ghosts, infected E. coli cells, and the phage that emerged from infected cells. D) Phage ghosts. E) The phage that emerged from infected cells.

phage ghosts

The following demonstrates which method of transcriptional regulation: - ON state: an Activator protein is bound to an operator sequence - OFF state: an inhibitor molecule binds to the Activator, causing the Activator to fall off the DNA. A) negative-inducible control B) positive-inducible control C) negative-repressible control D) positive-repressible control E) none of the above

positive-repressible control

If DNA polymerases could initiate DNA synthesis without needing a pre-existing 3' -OH to extend, which DNA replication component would be unnecessary? A) primase B) ligase C) telomerase D) helicase E) Okazaki fragments

primase

Sister chromatids separate during _______ . A) anaphase I and anaphase II B) metaphase and anaphase C) anaphase and anaphase II D) prophase I and metaphase II E) anaphase, anaphase I, and anaphase II

prophase I and metaphase II

If Fred Griffith's "transforming principle" was protein instead of DNA, which treatment of purified transforming principle would eliminate bacterial transformation? A. Protease B. DNase C. RNase D. Ultracentrifugation E. None of the above

protease

Pea plants in the F1 generation of Mendel's monohybrid crosses: A) were heterozygous for two different genes B) displayed a 3:1 phenotypic ratio C) were haploid D) showed the same phenotype as only one of the parental plants E) all of the above are true

showed the same phenotype as only one of the parental plants

Erwin Chargaff's experiments on the nucleotide composition of DNA had all of the following implications except... A) showing that the ratio of pyrimidines to purines in DNA was always equal. B) showing that DNA was the genetic material of a cell. C) showing that the DNA from different organisms can have different GC to AT ratios. D) suggesting the base-pairing arrangement of the nucleotides with Watson and Crick's double helix model of DNA structure. E) disproving the Phoebus Levene's tetranucleotide hypothesis.

showing that DNA was the genetic material of a cell

In the above diagram, which are be considered to be sister chromatids? A) the DNA molecules carrying #1 and #2 B) the DNA molecules carrying #2 and #3 C) the DNA molecules carrying #3 and #4 D) the DNA molecules carrying #1, #2, and #3 are all sister chromatids None of the above

the DNA molecules carrying #2 and #3

The Stubble (Sb) gene in Drosophila controls hair shape. Wild-type flies have thin, pointy hairs, whereas flies with one copy of the dominant Sb1 allele have thick, blunt hairs. You perform the same experiment multiple times, crossing male and female Sb1/+ flies together, and you consistently see offspring in the ratio of 1/3 wild-type flies to 2/3 flies with thick, blunt hairs. Which of the following would best explain your results? A) The Sb1 allele is recessive lethal. B) The Sb1 allele is codominant with the wild-type allele. C) The Sb1 allele is X-linked. D) The Sb1 allele is Y-linked. E) The Sb1 phenotype is incompletely penetrant.

the Sb^1 allele is recessive lethal

Which of the following is true about genes on the Drosophila X chromosome? A) They are all involved in female sex development. B) They are all involved in male sex development. C) They are upregulated in male flies. D) They are downregulated in female flies. E) They are randomly inactivated in the early embryo.

they are all upregulated in male flies

You have identified a mutation that deletes a gene's promoter. Without knowing anything else about the gene in question, how would you classify the allele produced by this mutation? A) this is likely to be a dominant allele B) this is likely to be a haplosufficient allele C) this is likely to be a gain-of-function allele D) this is likely to be a loss-of-function allele E) both A and C are correct

this is likely to be a loss-of-function allele

Seedless varieties of fruit have been developed by producing plants with abnormal euploidy, which causes abnormal meiosis and thus few seeds. Which of the following ploidies would you expect to be common in seedless varieties? A) triploidy B) octaploidy C) diploidy D) haploidy E) tetraploidy

triploidy

You being a sly yeast geneticist have moved the ADE2 gene into a region that you suspect is heterochromatin, and measure Ade2 enzyme activity in a culture (i.e. million of yeast cells): True or False: these data are consistent with the tested region being heterochromatin.

true

The diagram above shows two types of mitotic chromosomes, and each white box represents a gene. Which of the following statements is true? (A) #1 and #2 could be different alleles of the same gene. (B) None of these statements are true. (C) #1, #2, #3 and #4 could be different alleles of the same gene. (D) #3 and #4 could be different alleles of the same gene. (E) #1 and #2 must be different alleles of the same gene.

#1 and #2 could be different alleles of the same gene

The diagram below shows two types of mitotic chromosomes, and each white box represents a gene. Which of the following is true? (A) #1 and #2 could be different alleles of the same gene. (B) #1 and #3 could be different alleles of the same gene. (C) #3 and #4 could be different alleles of the same gene. (D) #1, #2, and #3 could be different alleles of the same gene. (E) None of the above.

#1 and #2 could be different alleles of the same gene.

Consider the following cross involving four pairs of alleles that behave in a Mendelian fashion: Aa bb cc Dd x AA BB Cc dd What is the probability that an offspring will show the following combinations of phenotypes? dominant A, recessive b, recessive c, recessive d (A) 1 (B) 1/4 (C) 0 (D) 3/8 (E) 1/8

0

Perform a chi-square analysis on the dataset from the previous question (20) to test whether these genes are behaving in a Mendelian fashion. You should get a p value in the range of: (A) 0.90 - 0.50 (B) 0.50 - 0.20 (C) 0.20 - 0.05 (D) 0.05 - 0.01 (E) 0.01 - 0.001

0.20 - 0.05

Mendel crossed tall pea plants with green pea pods to dwarf plants with yellow pea pods. All F1 plants were tall with green pods. What phenotypic ratio would you expect if you performed a testcross using one of these F1 plants? (A) 1 dwarf green : 1 dwarf yellow : 1 tall green : 1 tall yellow (B) 9 tall green : 3 tall yellow : 3 dwarf green : 1 dwarf yellow (C) 1 tall green: 1 dwarf yellow : 1 yellow green : 1 dwarf yellow (D) 9 tall green : 3 dwarf yellow : 3 dwarf green : 1 tall yellow (E) 3 tall, green : 1 dwarf, yellow

1 dwarf green : 1 dwarf yellow : 1 tall green : 1 tall yellow

Consider the following situation involving coat color and tail shape in mice. There is an allele of the agouti gene (AY) that is dominant to the wild-type allele (A) for coat color (gives a yellow coat in heterozygotes) but is also recessive lethal. Tail shape is controlled by a separate gene curly, and a recessive allele (c) causes mice to have curly (rather than straight) tails. In a cross between two mice of the genotype A/AY; C/c, what proportion of the living progeny would you expect to have yellow fur and curly tails? (A) 1/2 (B) 1/16 (C) 3/16 (D) 3/6 (E) 1/6

1/6

In humans, albinism is a recessive phenotype. Imagine that two individuals who are carriers for albinism and have blood type AB have a child. What is the likelihood that their child will have blood type AB and albinism? (A) 9/16 (B) 3/16 (C) 1/8 (D) 3/8 (E) 1/16

1/8

The Drosophila miniature gene is located on the X chromosome. Flies that are homozygous or hemizygous for a recessive m allele are significantly smaller than wild-type flies. You cross a homozygous miniature female to a wild-type male. What proportions of phenotypes and sexes should you expect in their offspring? (A) 75% normal females and 25% miniature males (B) 25% normal females, 25% miniature females, and 50% miniature males (C) 50% miniature males and 50% normal females (D) 50% miniature females and 50% normal males (E) 100% normal size, regardless of sex

100% normal size, regardless of sex

The Drosophila miniature gene is located on the X chromosome. Flies that are homozygous or hemizygous for a recessive m allele are significantly smaller than wild-type flies. You cross a true-breeding wild-type female to a miniature male. What proportions of phenotypes and sexes should you expect in their offspring? (A) 50% miniature females and 50% normal males (B) 75% normal females and 25% miniature males (C) 25% normal females, 25% miniature females, and 50% miniature males (D) 50% miniature males and 50% normal females (E) 100% normal size, regardless of sex

100% normal size, regardless of sex

Cows are diploid organisms with a haploid number (n) of 30. How many chromatids does a typical cow cell contain during the G2 phase of the cell cycle? (A) 15 (B) 30 (C) 60 (D) 120 (E) 240

120

Horses (Equus caballus) are diploid organisms (2n=64). How many chromatids does a horse cell contain during prophase of mitosis? (A) 128 (B) 32 (C) 64 (D) 256 (E) 16

128

How many different gametes can be produced by an individual with the following genotype? aaBbCcDdeeFf (A) 64 (B) 8 (C) 16 (D) 24 (E) 32

16

House cats (Felis domesticus) are diploid organisms (2n=38). A cat cell contains _____ chromosomes and _____ chromatids during prophase II of meiosis. (A) 19; 19 (B) 38; 72 (C) 72; 72 (D) 38; 38 (E) 19; 38

19; 38

You have a red molecule that specifically binds to Barr bodies, and a blue molecule that binds to any X chromosomes. You apply these two molecules to cheek cells from an atypical human with an XXY karyotype. When looking at these cells under the microscope, you should see ___ red signal(s) and ___ blue signal(s) in the nucleus of each cell. (A) 1 ; 0 (B) 1 ; 1 (C) 2 ; 1 (D) 0 ; 1 (E) 1 ; 2

1; 2

Typical human females have _____ autosomes and _____ sex chromosomes? (A) 22 ; 1 (B) 23 ; 2 (C) 44 ; 1 (D) 22 ; 2 (E) 44 ; 2

22; 1

Drosophila body color is controlled by an X-linked gene called yellow. Wild-type flies have gray bodies. What ratio of phenotypes should you expect to find in the progeny of a heterozygous gray-bodied female and a yellow-bodied male? (A) 100% gray offspring (B) 100% yellow offspring (C) 25% gray females; 25% yellow females; 25% gray males; 25% yellow males (D) 50% gray males; 50% yellow females (E) 25% gray females; 25% yellow females; 50% yellow males

25% gray females; 25% yellow females; 25% gray males; 25% yellow males

You isolate some cheek cells from someone with a karyotype XXXXYYYY, and you stain these cells with a fluorescent molecule that binds to alpha-4x-methH3-K9. How many bright dots should you expect to see in the nucleus of each cell? (A) 0 (B) 1 (C) 2 (D) 3 (E) 4

3

Consider the following cross involving four pairs of alleles that behave in a Mendelian fashion: AA bb Cc Dd x Aa Bb Cc dd What is the probability that an offspring will show all of the dominant phenotypes? (A) 1/4 (B) 3/16 (C) 9/16 (D) 1/8 (E) 3/8

3/16

If individuals III-5 and III-6 had a sixth child, what is the likelihood that this child would be unaffected? (A) 1/4 (B) 1/8 (C) 0 (D) 3/4 (E) 1/6

3/4

A black lab and a brown lab produced a litter consisting of yellow, black, and brown puppies. The mother is pregnant again with a second litter from the same father. What is the likelihood that the first puppy from this second litter will be brown? (A) 1/4 (B) 3/8 (C) 3/4 (D) 3/16 (E) 2/3

3/8

In the famous Hershey-Chase experiment, bacteriophage (phage for short) containing either radioactive sulfur (35S) or phosphorus (32P) were used to determine whether DNA or protein was the genetic material of phage. What was the result of the Hershey-Chase experiment? (A) 35S and 32P were both detected in infected E. coli cells and the phage that emerge from infected cells, suggesting that phage chromosomes contain both protein and DNA. (B) 32P was only detected in phage ghosts, suggesting that protein was being left behind. (C) 32P was detected in infected E. coli cells and the phage that emerge from infected cells, suggesting that DNA was the genetic material. (D) 35S was detected in phage ghosts, infected E. coli cells, and the phage that emerge from infected cells, suggesting that DNA was the genetic material. (E) 35S was detected in phage ghosts, infected E. coli cells, and the phage that emerge from infected cells, suggesting that protein was the genetic material.

32P was detected in infected E. coli cells and the phage that emerge from infected cells, suggesting that DNA was the genetic material

A group of 4 haploid organisms can contain, at most, how many alleles of a given gene? (A) 1 (B) 2 (C) 4 (D) 8 (E) 16

4

The following figure shows the results of DNase digestion of chromatin. How many nucleosomes are present in the ~800 base-pair (bp) band? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5

4

Assume a normal diploid Drosophila cell in G1 contains 100 picograms of DNA. Exactly how many picograms of DNA would a Drosophila gamete contain? (A) 25 (B) 50 (C) 100 (D) 200 (E) 400

50

Imagine a population of 100 diploid organisms. Each organism is homozygous with respect to gene A. What is the maximum number of different alleles for gene A that can exist in this population? (A) 1 (B) 50 (C) 2 (D) 100 (E) 200

50

Assume hair color in humans is a Mendelian trait controlled by a single gene, with blonde hair being recessive to black hair. If a black-haired man and a blonde-haired woman have one daughter who is blonde, and one son who is black-haired, what is the probability that their third child will have blonde hair? (A) 50% (B) 75% (C) 25% (D) 67% (E) 33%

50%

Genes c and d lie on opposite ends of the same chromosome (more than 50 cM apart). Assume recombination occurs once between the c and d genes in 100% of meiotic events. What percentage of the resulting gametes should be of the parental type? (A) 100% (B) 50% (C) 0% (D) It's impossible to say without knowing the exact map distance. (E) 25%

50%

Red-green colorblindness is a recessive X-linked condition. A woman who can see color but who had a colorblind father decides to have children with a man who is not colorblind. Their first son can see color. They are expecting another child, and they know it will be a boy. What is the probability that this child will be colorblind? (A) 0% (B) 25% (C) 33% (D) 50% (E) 67%

50%

Red-green colorblindness is a recessive X-linked condition. A woman who can see color but who had a colorblind father decides to have children with a man who is not colorblind. Their first son is colorblind. They are expecting another child, and they know it will also be a boy. What is the probability that their second son will be colorblind? (A) 50% (B) 66.7% (C) 25% (D) 0% (E) 100%

50%

You cross a true-breeding strain of eggplants that produces dark purple fruit to a true-breeding strain that produces white fruit. All of the resulting progeny produce light purple fruit. You take one of these F1 plants and cross it to the white-fruit strain. What proportions of phenotypes should you expect to see in the F2 offspring? (A) 100% light purple fruit (B) 50% dark purple; 50% light purple (C) 50% dark purple; 50% white (D) 50% light purple; 50% white (E) It is impossible to say, because these two traits may be linked.

50% light purple; 50% white

Cows are diploid organisms with a haploid number of 30. Immediately before S phase of mitosis, a typical cow cell contains _____ chromosomes and _____ chromatids? (A) 30 ; 60 (B) 15 ; 15 (C) 60 ; 60 (D) 15 ; 30 (E) 30 ; 30

60; 60

In the scenario described in the above question (23), the map distance between genes w and r is: (A) 7.5 mu (B) 0.75 mu (C) 1.5 mu (D) 15 mu (E) 30 mu

7.5 mu

Consider the following scenario for questions 27 and 28. Genes t and u are located 18 map units apart. You cross a Tu/tU individual to a tu/tu individual and examine 800 of their offspring. How many completely wild-type (phenotype TU) offspring should you expect to see? (A) 144 (B) 72 (C) 36 (D) 0 (E) 18

72

Consider three of Mendel's traits (stem height, flower color, and pea pod shape), where the dwarf height (d), white flower color (w) and constricted pod shape (c) alleles are recessive. What proportion of the progeny from a DdWwCc x DdWwCc cross will be tall plants with violet flowers and constricted pods? (A) 3/64 (B) 2/64 (C) 9/64 (D) 6/64 (E) 1/64

9/64

Which of the following is not a valid definition of a gene? (A) A region of a chromosome that controls a trait. (B) A sequence of nucleotides that encodes a functional RNA. (C) A molecular unit of heredity. (D) A region of DNA that is transcribed into RNA. (E) A portion of protein that is translated into RNA.

A portion of a protein that is translated into RNA

If one strand of DNA has the sequence ATTCGT, then the complementary strand will have the sequence: (Note: Your answer should be in the 5' to 3' orientation) (A) TAAGCA (B) TGCTTA (C) ATTCGT (D) ACGAAT (E) None of the above

ACGAAT

Which of the following genotypes corresponds to the starred box in the Punnett square below? AD Ad aD ad x AD Ad aD ad What will be the 2nd box in the last row? (A) Aadd (B) AADD (C) aaDd (D) AaDd (E) AaDD

Aadd

What is the most likely pattern of inheritance for the condition shown in this pedigree? I. 1 is a circle and is blank I. 2 is a square and is blank I. 3 is a circle and is blank I. 4 is a square and is blank II. 1 is a circle and blank II. 2 is a square and is filled II. 3 is a circle and is filled II. 4 is a square and is blank II. 5 is a circle and is blank II. 6 is a square and is filled II. 7 is a circle and is filled II. 8 is a square and is blank (A) X-linked Recessive (B) Autosomal Recessive (C) X-linked Dominant (D) Y-linked Dominant (E) Autosomal Dominant

Autosomal Recessive

In the diagram below, crossing over might occur between which chromatids? (A) Between C and D (B) Between A and D (C) Between A and B (D) Between D and E (E) Between E and F

Between A and D

Which of the following genotypes describes an individual that is hemizygous for X-linked genes? (A) 46, XY (B) Both 45, XO and 46, XY (C) 45, XO (D) Both 45, XO and 46, XX (E) 46, XX

Both 45, XO and 46, XY

You have identified a novel antibiotic and want to test it for mutagenicity using the Ames Test. You obtain the following results: Sample ................ Number of His+ revertant colonies saline............................... 7 rat liver enzymes in saline............................... 9 antibiotic in saline............................ 103 antibiotic plus rat liver enzymes in saline ............. 212 What conclusion is most consistent with this data? (A) Neither the antibiotic nor its metabolites are mutagenic. (B) The antibiotic increases the mutagenic activity of rat liver enzymes. (C) The antibiotic is not mutagenic, but its metabolites are. (D) The antibiotic is mutagenic, but it is metabolized into non-mutagenic metabolites. (E) Both the antibiotic and its metabolites are mutagenic.

Both the antibiotic and its metabolites are mutagenic

Cystic fibrosis is an autosomal recessive disorder. Which of the following pedigrees is most consistent with the inheritance of cystic fibrosis? (A) A (B) B (C) C (D) A and C are equally good answers

C

An individual with the genotype CCDd can produce which of the following gamete types? (A) CC and Dd (B) CD, Cd, cD and cd (C) CD and Cd (D) CCDd (E) C, c, D and d

CD and Cd

If you were to compare red blood cells from a typical human and a human with sickle-cell anemia, what should you expect to find? (A) The wild-type cell would contain more alleles of the beta-globin gene. (B) Aggregated strands of hemoglobin in the wild-type cells. (C) Comparable amounts of beta-globin mRNA in both samples. (D) No beta-globin mRNA in cells from the sickle-cell patient. (E) The cells would look identical.

Comparable amounts of beta-globin mRNA in both samples

Phoebus Levene's tetranucleotide hypothesis, if true, would have eliminated the possibility that DNA was the genetic material because... (A) DNA would not possess the nucleotide sequence diversity required to store information. (B) DNA would not be able to associate with chromosomes. (C) DNA would not be stable enough to reliably store information. (D) DNA could not undergo semi-conservative replication. (E) DNA would not be transmissible to gametes.

DNA would not possess the nucleotide sequence diversity required to store information

Gammarus duebeni is a sexually reproducing species of crustacean. Offspring produced early in the mating season develop as male, whereas offspring produced late in the season develop as female. What is the most likely explanation for this phenomenon? (A) G. duebeni uses an environmental sex determination system. (B) Males are haploid and females are diploid in this species. (C) G. duebeni uses a genetic sex determination system. (D) G. duebeni is an anisogamous species. (E) G. duebeni is an isogamous species.

G. duebeni uses an environmental sex determination system

Consider the following DNA sequence: 5'-ATCGTTAGC-3' If the fourth nucleotide of this strand were mutated to an A, what would be the sequence of the complementary strand? (Answer in the 5' to 3' direction) (A) TAGTAATCG (B) GCTAATGAT (C) TAGCAATCG (D) GCTAACGAT (E) ATCATTAGC

GCTAATGAT

Most novel (new) mutations that occur in humans are not harmful because: (A) Most mutations are gain-of-function, causing them to work better. (B) Genes represent only about 10% of your genome. (C) Most mutations are haplosufficient. (D) Most genes are haploinsufficient. (E) Most mutations occur in the promoter regions of genes.

Genes represent only about 10% of your genome

If mutations were specifically induced as a direct response to selective pressure, what would have been the result of Esther and Joshua Lederberg's replica printing experiment? (Reminder: the experimental design was to isolate colonies on a plate grown without antibiotic, and then replica print to multiple plates with antibiotic). (A) Every single colony from the plate grown without antibiotic would also grow on each of the different antibiotic plates. (B) Resistant colonies would never appear on any of the different antibiotic plates. (C) Resistant colonies would always arise in the exact same location on each of the different antibiotic plates. (D) Resistant colonies would appear to be randomly distributed across the different antibiotic plates. (E) The number of resistant colonies on each of the different antibiotic plates would greatly fluctuate.

Resistant colonies would appear to be randomly distributed across the different antibiotic plates

Which of these statements is true concerning diploid cells in metaphase of mitosis? (A) Chromatin is in relaxed open state. (B) Non-sister chromatids have undergone crossing over. (C) Tetrads are aligned at the equatorial plate. (D) Sister chromatids share a common centromere. (E) Non-sister chromatids always contain the same alleles.

Sister chromatids share a common centromere.

The human ABO blood type system is controlled by three alleles of the I gene (IA, IB, and i), which encodes an enzyme that attaches sugars to the H substance protein on the surface of red blood cells. Both IA and IB are dominant to i, and they are codominant with one another. What best explains why alleles IA and IB are codominant? (A) This gene is located on the X chromosome. (B) The I^A and I^B alleles are both functional but encode different gene products. (C) The I^A and I^B alleles inactivate one another. (D) This gene is haploinsufficient. (E) The i allele is due to a loss-of-function mutation.

The I^A and I^B alleles are both functional but encode different gene products

You have a true-breeding Drosophila line that has blue eyes and curved wings, and when you cross these flies to wild-type flies, all of the F1 progeny look wild type (red eyes and straight wings). You cross an F1 dihybrid male to several of your true-breeding blue-eyed, curved-wing females and you obtain the following F2 progeny. 154 red-eyed, straight wings 148 blue-eyed, curved wings 115 blue-eyed, straight wings 111 red-eyed, curved wings You decide to perform a chi-square analysis to test whether these two traits are behaving in a Mendelian fashion. Your null hypothesis should be: (A) The b and c genes assort independently, and we should observe 1:1:1:1 phenotypic ratio in the F2. (B) The b and c genes assort independently, and we should observe 9:3:3:1 phenotypic ratio in the F2. (C) The b and c genes do not assort independently, and we should observe a 1:1:1:1 phenotypic ratio in the F2. (D) The b and c genes do not assort independently, and we should observe a 9:3:3:1 phenotypic ratio in the F2. (E) The b and c genes do not assort independently, therefore we cannot make any predictions about ratios in the F2.

The b and c genes assort independently, and we should observe 1:1:1:1 phenotypic ratio in the F2

Consider the following scenario for questions 20-22. You are characterizing a new mutation in fruit flies that causes a blue-eye (b) phenotype. You have a true-breeding line that has blue eyes and curved wings, and when you cross these flies to wild-type flies, all the F1 progeny are wild type (red eyes and straight wings). You know that the curved wing trait is controlled by the c gene on the second chromosome. You cross your F1 dihybrids back to your original true-breeding blue-eyed, curved wings strain and you obtain the following F2 progeny. 109 red-eyed, straight wings 115 blue-eyed, curved wings 85 blue-eyed, straight wings 91 red-eyed, curved wings You decide to perform a chi-square analysis to determine whether gene b is also located on the second chromosome. Your null hypothesis should be: (A) The b and c genes assort independently, and we should observe a 1:1:1:1 phenotypic ratio in the F2. (B) The b and c genes do not assort independently, and we should observe a 1:1:1:1 phenotypic ratio in the F2. (C) The b and c genes do not assort independently, and we should observe more parental gametes in the F2. (D) The b and c genes assort independently, and we should observe a 9:3:3:1 phenotypic ratio in the F2. (E) The b and c genes do not assort independently, and we should observe a 9:3:3:1 phenotypic ratio in the F2.

The b and c genes assort independently, and we should observe a 1:1:1:1 phenotypic ratio in the F2

Immediately after S phase of meiosis II, a typical human cell contains _____ chromosomes and ________ chromatids? (A) 23; 23 (B) 23; 46 (C) 46; 46 (D) 46; 92 (E) There is no S phase during meiosis II, so this question makes no sense.

There is no S phase during meiosis II, so this question makes no sense.

Tortoiseshell cats are almost always female. However, there are rare examples of male tortoiseshell cats. Based on what you have learned about sex determination and dosage compensation in mammals, what is the most likely explanation for this phenomenon? (A) These are XO males (B) Trick question! All cats are female. (C) These are XY males with mutations in the SRY region (D) These are XXY males (E) They had a large number of spontaneous mutations in their fur during development

These are XXY males

You are a pea plant geneticist and you have isolated a new recessive mutation that creates dwarf pea plants. You also happen to have some of Mendel's original stock of true-breeding dwarf plants. For fun, you cross one of your newly isolated dwarf plants to one of Mendel's original dwarf plants, and you find that all of their offspring are tall! What is the most likely explanation for this miraculous result? (A) These two alleles are codominant. (B) These are recessive alleles of two different haplosufficient genes. (C) These are recessive alleles of two different haploinsufficient genes. (D) Mendel's alleles have expired. (E) Mendel's dwarf allele is dominant to my new allele.

These are recessive alleles of two different haplosufficient genes

Which of the following is true about genes on the X chromosome in mammals? (A) They are all involved in male sexual development. (B) They are all involved in female sexual development. (C) They are upregulated in males compared with females. (D) They are all haploinsufficient (E) They have evolved to function properly in a hemizygous state.

They have evolved to function properly in a hemizygous state

One of Mendel's monohybrid cross experiments involved crossing true-breeding green-pod plants with true-breeding yellow-pod plants. All F1 progeny had green pods. Using the symbol system we learned in class, which of the following would be an accurate way of depicting the parental cross? (A) GY x gy (B) YG x yg (C) GG x yy (D) GG x gg (E) YY x yy

YY x yy

Telophase begins with the initiation of which process? (A) cytokinesis (B) movement of centrioles to opposite poles (C) alignment of mitotic chromosomes at the equatorial plate (D) condensation of DNA into compact mitotic chromosomes (E) breakdown of the nuclear envelope

cytokinesis

A chi-square value is a measure of the total ________ between observed and expected outcomes for a set of measurements. (A) rescuscitution (B) recessiveness (C) deviation (D) domination (E) degrees of freedom

deviation

A version of a gene that encodes an enzyme with only 30% of the activity of the wild-type protein is best described as a ____________: (A) haplosufficient allele (B) haploinsufficient allele (C) hypomorphic allele (D) amorphic allele (E) null allele

hypomorphic allele

Sexual reproduction is likely an evolutionary adaptation to: (A) increase genetic diversity so diploid organisms can evolve faster. (B) decrease genetic diversity and remove harmful mutations from the gene pool. (C) increase genetic diversity so diploid populations can withstand attacks from pathogens. (D) decrease the rate of molecular evolution and create living fossils. (E) decrease genetic diversity so haploid organisms can hide from pathogens.

increase genetic diversity so diploid populations can withstand attacks from pathogens

What amino acid is encoded by the third codon of the following coding sequence? ATGCATATTATTTAG (A) Trp (B) lle (C) Met (D) Ala (E) Tyr

lle

A _____ allele will be recessive to a wild-type allele for a gene that is ______. (A) loss-of-function ; dominant (B) loss-of-function ; haplosufficient (C) gain-of-function ; haploinsufficient (D) haplosufficient ; gain-of-function (E) gain-of-function ; loss-of-function

loss-of-function ; haplosufficient

If DNA polymerase could synthesize DNA in both the 5' to 3' direction and 3' to 5' direction, what would not be needed? (A) telomerase (B) dNTPs (C) primase (D) helicase (E) ligase

telomerase

Gene expression involves which of the following processes? (A) mutating DNA sequences to create gain-of-function alleles (B) transcription of a functional RNA by RNA polymerase (C) translating a protein sequence into RNA via the ribosome (D) duplication of chromosomes by DNA polymerase (E) transporting chromosomes from the nucleus to the cytoplasm

transcription of a functional RNA by RNA polymerase

In the above question (27), which of the following could be the genotype of an offspring from one of the "recombinant" classes? (A) Tu / tu (B) TU / TU (C) TU / Tu (D) Tu / tU (E) tu / tu

tu / tu

You have two male flies that are visually identical; one carries a valuable new mutation that you are interested in studying, while the other is just a standard wild-type fly. Unfortunately, you have mixed them up. However, even though they both have red eyes, you do know that the fly with the valuable mutation is also heterozygous (Ww) for the white eye color allele, whereas the other fly is homozygous (WW) for the wild-type eye-color allele. You decide to perform test crosses to tell them apart. If you mate each male with females of the genotype _____, you should expect ______% of the progeny from the fly with the valuable mutation to have white eyes. (A) Ww; 100% (B) Ww; 50% (C) ww; 50% (D) ww; 25% (E) ww; 100%

ww; 50%

Perform a chi-square analysis on the dataset from question 2 using the proper expected phenotypic ratio. You should obtain a chi-square value of approximately _______ and a p value in the range of _______. (A) x^2 = 1.9 ; p= 0.90-0.50 (B) x^2 = 3.3 ; p= 0.50-0.20 (C) x^2 = 4.9 ; p= 0.20-0.05 (D) x^2 = 11.1 ; p= 0.05-0.01 (E) x^2 = 15.3 ; p= 0.01-0.001

x^2 = 11.1 ; p= 0.05-0.01