Question

42. true-breeding (homozygote) red flower plant was bred with a true-breeding pure white flower plant (therefore P generation). What flower color you expect in Fl progeny? a) Only red b) Only white c) Only pink d) Both red and white If F, offspring (from the above question # 41) were crossed with each other, what flower color you expect in F2 progeny? a) Only red b) Only white c) Only pink d) All of the above What phenotype ratio you expect in F2 offspring (in the above question #42)? 43. Date: 46. If a mother has type A blood and her son has type o blood, what are the possible blood types of her son's biological father? a) Type O only b) Types A or o c) Types B or 0 d) Types A, B or o 47. Huntington's disease is an example of a) Sex-linked trait b) Sex-influenced trait c) Sex limited trait d) Lethal allele 48. What is the condition known as when expression of one gene masks or modifies the expression of other gene? a) Lethal alleles b) Codominance c) Polygenic d) Epistasis Which of the following ratio in phenotype is not the result of epistasis? a) 9:7 b) 9:6:1 c) 9:3:4 d) 9:3:3:1 A female who is a carrier of color blindness (an X-liked disorder) marries a man with normal color vision. What is the probability that her daughter will be colorblind consider daughters only)? 44. 50. a) 1:1 b) 3:1 c) 1:2:1 n ov d) 9:3:3:1 What genotype ratio you expect in F2 offspring (in the above question #42) a) 1:1 b) 3:1 c) 1:2:1 bei d) 9:3:3:1 Human blood groups are found on three separate alleles 14, 15 and 1º. Which of the following blood type is the result of the so-called codominance?? a) A b) B c) O 45. a) 0% b) 25 % c) 50 % d) 75 % e) 100% d) AB

Answer 1

41) this is an example of incomplete dominance when true-breeding red flowers are crossed with true-breeding white flowers, let the alleles be R-red, W-white 'then the true-breeding red plant is RR a true-breeding white plant is WW

then the cross is

RR $\times$ WW

RW

so progenies are heterozygous so they are pink so the answer is

c) only pink

42) RW $\times$RW

	R	W
R	RR (red)	RW (pink)
W	RW (pink)	WW ( white)

in the F2 it is possible to get white, red, and pink so the answer is d) all of the above

43) the phenotypic ratio is

red:pink:white=1:2:1

so answer is c) 1:2:1

44) the genotypic ratio is

RR:RW:WW=1:2:1

so answer is 1:2:1