Genetic Patterns in Tribbles #1 a) Red b) black c) pheno 3:1 red to black geno 1:2:1 RR Rr rr P1 RR x rr F1 Rr Rr x Rr F2 RR Rr Rr rr

Tribbles #2 A. Codominance both blue & yellow hairs HB and HY HB HY x HB HB green blue HB HY HB HB HB HB HY ratios Pheno: 50% blue hair 50% green (both) 1:1 Geno: 50% HB HB 50% HB HY

#3 a) Red, Blue and Yellow HR HB HY b) black and white hb hw c) black is recessive to red, blue, & yellow, but black is dominant to white

#4 A) spotted and blue hair B) solid and black hair C) T (spots) t (solid) HB hb D) To get a 9:3:3:1 ratio that is a normal dihybrid heterozygous cross: TtHBhb x TtHBhb THB Thb tHB thb THB Thb tHB thb

#5 A) spotted and red hair B) solid and white hair C) white spots will not show on a white background (they blend in, but the spotted genes will still be there!)

#6 A) gene D seems to control how much pigment is made B) There is a blending of color amounts, therefore this is incomplete dominance C) no pigment is made therefore they are white D) hwhw dd hwhw TT or tt white hair no pigment white hair & spots/solid

#7 A) HB HR DD x HY HR dd B) HY HR Dd purple with incomplete pigment production

#8 A) must be sex-linked if only males have the trait (or a majority of males have trait) B) HB HB XnY x HB HB XNXn

#9 Genes in Tribbles chart TRAIT Dominant Allele Recessive Allele Coat Color Blue HB Red HR Yellow HY Black hb White hw Coat Pattern Normal XN Plaid Xn Pigment Production Normal D No pigment d Spots Spots T Solid t

Additional Practice http://biology.clc.uc.edu/courses/bio105/geneprob.htm This is on my website under links also!! Go there for practice.