Legend: S spotted Genotypes: P1 SS & ss F1 Ss ss plain F2 (with ratio) 1SS :2 WSs: 1ss. Legend W white White bull 1 Ww red cows ww ww red

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1 On my honor, this is my work GENETICS 310 EXAM 1 June 8, 2018 I. Following are 3 sets of data collected from crosses: 1. Spotted by Plain gave all spotted in the F1 and 9 spotted and 3 plain in the F2. Create a legend to define the results and use your legend to show genotypes in each generation: Legend: S spotted Genotypes: P1 SS & ss F1 Ss ss plain F2 (with ratio) 1SS :2 WSs: 1ss 2. White bull 1 was mated to 8 red cows. Four of the calves were white and four were red. When a male (2) and a female (3) among the white progeny from this cross were mated, their calf was red. Use this information to create a legend for this trait and use it to provide the genotypes of the designated animals: Legend W white White bull 1 Ww red cows ww ww red White male 2 Ww White female 3 Ww 3. Peas from 2 different truebreeding cultivars resistant to a fungal pathogen were crossed and all the F1 progeny were resistant. Produce legends and show the expected F2 progeny phenotype(s) and ratio of resistant and susceptible if: a) Resistance is one single gene: Legend R resistant F2 expected ratio 3 Resistant : 1 Susceptible rr susceptible b) Either of wo independent genes confer resistance, each via a dominant allele: Legend R1 resistant Predicted F2 ratio r1r1 susceptible 15 resistant : 1 susceptible R2 resistant r2r2 susceptible (9 R1_, R2 resistant 3 R1, r2r2 resistant 3 r1r1, R2 resistant 1 r1r1, r2r2, susceptible)

2 II. Following is a pedigree showing the occurrence of a rare condition a) How is the trait inherited? Single gene recessive b) What is the probability each individual is heterozygous? /3 4 2/ /3 III. In maize: E_ normal seed P_ purple seed B B broad leaf L_ ligule ee no seed made pp yellow seed B B medium ll no ligule BB narrow leaf Silks from a plant with the genotype Ee, Pp, B B, ll are fertilized with pollen from an Ee, Pp, BB, Ll plant. a) How many kinds of gametes can the parents make? Female 2*2*2*1 male 2*2*1*2 b) What are the odds of a E, P, B, L pollen grain? ½ x ½ x 1 x 1/2 c) What fraction of the seeds formed on the ear of the female will have the genotype: EE, Pp, B B, ll? 1/3 x ¼ x 1/2 x 1/2 d) What fraction of the seeds formed will be yellow and grow into narrow leafed plants with ligules? 1 x ¼ x ½ x 1/2 e) A medium leafed (B B) plant is self pollinated. If 20 seeds are selected at random: 1) What if the probability that 5 will grow into broad leafed plants, 10 into medium and 5 into narrow leafed plants: (Show results as a formula only) 20!/51x101x5! X (1/4) 5 (1/2) 10 (1/4) 5 2) What are the odds that at least one will be narrow leafed? 1-(3/4) 20

3 IV. Give a very brief definition and a real or made up example illustrating: a) teratogen -an agent that causes birth defects to a developing fetus ex s thalidomide, Zika etc b) variable age of onset -an inherited condition that can manifest at various stages of life ex Huntington disease c) recessive lethal an allele that causes death (or just inability to reproduce) when present in a homozygous condition with no effect on heterozygotes. Ex cystic fibrosis, sickle cell with no treatment etc. d) co-dominance when both alleles are expressed, often in different cells as in roan cattle but also in the same cell in AB type blood e) phenocopy an environmental mimic of a genetic defect ex flipper arms from thalidomide exposure or homozygous recessive for phocomelia or albino plants from a mutation or herbicide exposure f) genetic heterogeneity - when several to many different genetic defects cause the same phenotpype, exs blindness, deafness, cataracts etc. V. HLA genes are critical to the ability to recognize self versus non-self. A man has the combination A B and his wife is A B a) Give two examples of HLA genotypes that would be expected in their children and 2 more b) Give 3 different examples of HLA genotypes that could serve as organ donors for the man etc VI. In the chart below write the ABO, MN and Rh (+ or -) blood group combinations (if any) that are incompatible with each parent/baby combination.

4 Baby 1 O N - 2 A MN + 3 B M - 4 AB MN + Couple A M + O MN + O N + B MN B N - AB, N + A, N - B M - MN ABO MN MN ABO/Rh MN MN ABO/MN ABO ABO/MN ABO/Rh If possible, tell which baby would be sent home with each couple: Couple Which, if any, of the mom s would need a shot of Rhogam? None rh- mom hd rh- baby VII. A diploid organism is heterozygous for genes A, B and D on chromosomes 1-3, respectively. A) Show the chromosomes with alleles at metaphase in mitosis and meiosis I. Mitosis Meiosis I B. Assuming there is no exchange between paired or unpaired chromosomes, write the genotypes of the two daughter cells of each division. Mitosis Aa, Bb Dd & Aa, Bb, Dd Meiosis I A, B, d & a, b, D if as shown here

5 VIII. Data from a cross of two inbred corn varieties identified five QTLs associated with the number of rows of kernels on the cob. In this case, it was determined that each contributing alleles added 1 row to a 4 row base. Here is a summary of the crosses and results: Parents P1, 8 rows P2, 10 rows F1, 9 rows F2, 11 unique row numbers a) Give potential genotypes for the truebreeding parents and the F1 P1 A A B B CCDDEE P2 AABBC C D D E E F1 A AB BC CD DE E b) What are the lowest and highest row numbers predicted in the F2 plants? Lowest 4 highest 14 c) At what frequency are these classes expected? Lowest (1/4) 5 highest (1/4) 5 d) Did transgessive segregation occur in this example? yes How can you tell? F2 range of 4-14 beyond parents of 8 and 10 e) The average variance in the two parents and F1 was 1 but in the F2 it was 4. Calculate H 2 for row number, showing the source of your data. VT = 4 Ve= 1 so Vg = 3 and H 2 = 3/4 IX. True or false: F Kuru is inherited via maternal lineages. T Identical twins eared apart have remarkably similar IQ scores in the UMinn. study. F A heritability of 1 in a study of egg weight in leghorns means changing the diet could not affect egg weight. T Monozygotic twins are always the same sex. F F T Cyrils Burt s conclusions on the heritability of IQ are significantly out of line with more recent studies. Identical (MZ) twins are born more frequently than fraternal (DZ) twins. Any level of trait discordance in identical twins implies an environmental effect.