In humans, the recessive allele that causes a form of red-green colour blindness (c) is found on the X chromosome. a.) Determine the genotypes and phenotypes of the F1 generation from a colour-blind father and a mother who is homozygous for normal colour vision. b.) Determine the genotypes and phenotypes of the F1 generation from a father who has normal colour vision and a mother who is heterozygous for colour vision. c.) Draw a Punnett square to determine the genotypes of parents that could produce a daughter who is colour-blind

In humans, albinism (lack of skin pigment) is an autosomal recessive trait. The first child of two normally pigmented parents is an albino. Which of the following is true about this family? SELECT ALL THAT ARE CORRECT. A) Their first child (described above) has a homozygous recessive genotype B) The next child born to this couple has a 25% chance of being albino. C) If the next child born to this couple is male, he has a greater chance of being albino. D) The parents are both heterozygous for albinism. E) The probability of their second child being albino is 0% F) If the second and third child born to this couple are albino, the fourth child has 100% chance of also being albino.

3)The inability to synthesise chlorophyll is a recessive characteristic in tobacco plants. If a tobacco plant know to be heterozygous is self pollinated, and 600 of its seed were germinated, a) how many would you expect to produce albino (completely unpigmented) plants? b) how many would be expected to have the parental genotype? c) why is this cross the only way to produce albino tobacco plants

Dominant alleles are so called because under most circumstances they____ a) code for genes that are never considered lethal c) they are expressed whenever present d)code for desired traits only e) they are found on all 22 somatic chromosomes and not on sex chromosomes

A particular flower can be purple, blue, red or white. Two different pure-breeding white plants are crossed and the F1 are then crossed to produce an F2 generation. What might a 9:7 phenotypic ratio in the F2 indicate? A) additivity B) codominance C) recessive lethality D) reciprocal recessive epistasis E) dominant epistasis Explain each answer.

Stacey and Rishi are expecting fraternal twins, a boy and a girl. Stacey and Rishi have normal vision, but both of their fathers are colour vision deficient (CVD, a X-linked recessive trait). a) Draw a pedigree for their family b) Complete a Punnett square to show the cross between Stacey and Rishi. c) What is the probability that the baby will be a girl with CVD? d) What is the probability that the baby will be a boy with normal vision?

An unaffected woman for a human disorder marries and unaffected man and they have children. This results in 3 affected sons, and one unaffected daughter, which ends up having children later on with an unaffected man and has 2 affected sons. A) Draw a simple pedigree diagram for this family, including a legend. B) What is the likely mode of inheritance of this trait: Please explain C) Provide the genotypes of the original mother and the daughter. Use a capital letter for the dominant allele and lowercase letter for the recessive allele. D) If one of the affected sons from the original marriage marries a 2nd cousin that is a carrier of this trait and has children, what is the probability that they will have 3 affected sons?

The genes S and T show complete linkage. If a heterozygous individual (whose parents were SSTT x sstt) were to produce gametes, which distribution below is most likely? a) S,s,T and t gametes in a 1:1:1:1 ratio b) ST and st gametes in a 1:1 RATIO c) ST, St, sT and st gametes in a 1:1:1:1 ratio d) SsTt gamete is the only type produced

Part A) You cross a fly with straight wings with a fly with curved wings to produce the F1 generation, all of which exhibit straight wings. In the F2 generation, you observe 65 straight-winged flies and 16 curved-wing flies. Based upon the results, which phenotype is recessive? Part B) You think this trait is controlled by a single gene, but the F2 numbers don’t quite match a 3:1 expected ratio. Perform a chi-square analysis to determine if the variation you observe is due to chance or not. Based upon this determination, would you keep or reject the “null hypothesis”? Show your work and explain your reasoning.

Now assume that the pedigree shown in question 1 shows the inheritance of a rare genetic disease. a) The disease is most likely autosomal dominant b) The disease is most likely autosomal recessive c) The disease is equally likely to be either autosomal dominant or autosomal recessive, but cannot be x-linked d) Cannot be determined from the information given