GSS Week 3 JeopardyChapters 2-69/24, 9/25Chromosomes100- How many chromosomes does a human egg cell have?A- 23, In haploid form200- How many classifications of chromosomes are there?A- 4, metacentric, submetacentric, acrocentric, telocentric300- What holds sister chromatids together until anaphase in mitosis?A- Cohesin400-What classification of chromosomes do humans NOT have?A- Telocentric500- What is the difference between euchromatin and heterochromatin?A- Euchromatin will be expressed while heterochromatin will not be expressed.Mitosis and Meiosis100- How many checkpoints are there in the cell cycle?A-3; G1, G2, Metaphase200- In what stage of mitosis do sister chromatins separate and move to opposite poles?A- Anaphase300- In what phase of meiosis do chiasmata form?A- Prophase I400- Down’s syndrome is an example of what sort of disjunction?A- Trisomy (2n+1)500- Why don’t sister chromatids separate during Anaphase I of Meiosis?A- Shugoshin protects cohesin at the centromere of the sister chromatids and is degraded at anaphase II so that the cohesin can be degraded.Mendelian Genetics and Probability100- What term do we use to describe alternate forms of the same trait?A- Alleles200- A test cross is a cross between what phenotype and which genotype?A- Dominant phenotype x Homozygous recessive300- What occurs in a reciprocal cross?A- The phenotypes of the male and female parents are reversed.400- What is the expected phenotypic ratio in a dihybrid cross of two heterozygous parents?A- 9:3:3:1500- In a progeny of 200 offspring, how many will be AabbCcDD with the parental cross of AaBbCCDD x aaBbccDD?A- ½ x ¼ x 1 x1 x 200= 25 Pedigrees100- What does a double line in a pedigree indicate?A- Consanguinity200- If an individual marries into a pedigree of a specific trait, we can assume that he/she is what genotype?A- Homozygous for not having the trait300- Tay Sachs disease is an example of what sort of trait?A- Autosomal recessive400- Which two traits can skip generations in a pedigree?A- Autosomal recessive and X-linked recessive500- What sort of trait could NOT show a pedigree where all carriers are male but not all males are carriers?A- X-linked dominant would have to have a female carrierSex-Linked Characteristics100- In humans, which sex is heterogametic.A- Male; XY200- How much of a population has to have a trait to consider it wild-type?A- >1%300- In drosophilia, if the ratio between X chromosomes and autosomal chromosomes is between .5 and 1, what is its sex?A- “Intersex”400- If an SRY gene accidentally crosses over to an X chromosome and that X chromosome is used to make a baby, what sexual phenotype will the child have?A-Male, but genotype will be female.500- Why are all calico cats female?A- Calico cats have a distinct fur pattern that comes about due to the inactivation of one X chromosome, meaning that they must have two X chromosomes. Extensions of Mendelism100- What is the only genotype for someone who has O-type blood?A- ii200- Which blood genotype could accept a donor of any blood type?A- IAIB300- What is a full color chinchilla’s genotype if, when mated with a albino chinchilla, there are some offspring that are Himalayan?A- CCh400- What is the phenotypic ratio in a recessive epistasis dihyrbid heterozygous cross?A- 9:3:4 Labrador retrivers500- Why, in the case of lethal alleles in the yellow mice, is lethality recessive?A- Because it takes two alleles to cause death. A mouse can have the dominant allele and be yellow but the one dominant allele is not enough to cause death.GSS Week 4 WorksheetChapter 710/1 , 10/3Short Answer1.) Who did the fruit fly experiments that were the foundation for the research of linked genes?Thomas Hunt Morgan2.) How many centiMorgans is a recombination frequency of 10%?103.) What are the gene ratios between parental and recombinants in a test cross when the genes are not linked?1:1:1:1 parental: parental: recombinant: recombinant4.) Genes farther apart on the chromosome will have a higher or lower recombination frequency?Lower, less likely to cross over with one another.Problem Solving1.) In the garden pea, orange pods (orp) are recessive to green pods (Orp) and sensitivity to pea mosaic virus (mo) is recessive to being resistant to the virus (Mo). A plant with orange pods and sensitivity to the virus was crossed with a true-breeding plant with green pods and resistance. The F1 plants were then testcrossedwith plants with orange pods and sensitivity to the virus. The following results were obtained:160 orange pods, virus sensitive165 green pods, virus resistant36 orange pods, virus resistant39 green pods, virus sensitive.A. Conduct a Chi-Square to see if these genes are linked.If they weren’t linked the ratio would be 1:1:1:1, so 100 progeny of each. Chi squareyields 60^2/100 + 65^2/100 + -64^2/100 + -61^2/100 = 156.5 so we reject the hypothesis that the genes separate independently. So, genes are linked.B. Draw the chromosomes of the parental generation, the F1 generation and the testcross.Parental will be Orp/Mo Orp/Mo x orp/mo orp/moF1 will be Orp/Mo orp/mo Test cross will be orp/mo orp/moC. If they are linked, calculate the map distance between the genes on the chromosome.# recombinants/total progeny x 100 = (36+39)/ (36+39+160+165) x 100= 18.8 mu2.) The following numbers were obtained for testcross progeny in Drosophilia:+ M + 218W + F 236+ + F 168W M + 178+ M F 95W + + 101+ + + 3W M F 1Total 1000A.) Based on this chart, what are the parental phenotypes, the single crossovers, anddouble cross overs?Top two are parentals, middle 4 are single cross overs, bottom two are double crossovers.B.) What gene is in the middle?Double crossovers are different from parentals by M, so M is in the middle.C.) Construct a genetic map with units of these three genes on a chromosome.Between W and M: 168+178+3+1= 350/1000= 35 muBetween F and M: 95+101+3+1= 200/1000= 20 muI will then draw the chromosome on the board with correct units labeled.GSS Week 5 WorksheetChapter 7 & 1210/8 , 10/10Short Answer1.) Sea urchin DNA, which is double stranded, was shown to contain 17.5% of its bases are cytosine. What percentages are the other three base pairs?C=G so 17.5% G, A=T=32.5%2.) What are the four major steps in DNA replication?Initiation, unwinding, elongation, and termination.3.) Which nitrogenous bases are purines and which are pyrimidines? What’s the difference between the two?Adenine and Guanine are purines and Cytosine and