1. Red-green colour blindness is caused by an4nm melba;7 89o*v zmh X-linked recessive allele. In the pedigree chart below which individuals must be carriers of the red-green colour blindness allele? 4mbvn h97eam o8;z*m l

  2. If the parents in the pedigree chart above had a foutqqd9s-rxhlfz90z t l 2g ,9d.q+mrc-rth child who was female, what would be th0d , z9cl2+-zqdrtfx q-l99.qm tsrh ge probability that she was colour blind?

  3. In Labrador dogs, o24wzzivid6n3* 3tk ablack coat is dominant over chocolate coat. The genotype of a black male labrador is unknown. How can the 3vwi*ia3t dz4ok6 z2ngenotype of this black Labrador be determined?

  4. Which of the following bes yctm ,.btm7qo4a9gb( t defines the term, “gene”?

  5. Phenylketonuria (PKU) is an inheritcs d 57;oacj7fed human disease caused by a recessive autosomal allele in a gene which codes for an enzyme needed to convert phenylalanine to tyrosine. The PKU allele produces a7sadj57f c co; non-functional enzyme.
Which of the following statements are correct?
I. Two parents heterozygous for the condition could have a child with PKU.
II. If the mother of the child is homozygous and not affected by PKU, her children will not be affected.
III. The polypeptide sequence of the enzyme of an affected person is identical to a person without the condition.
IV. Two parents who are not affected with PKU cannot have a child with the disorder.

I. Identify which of the alleles, yellow or green, is dom4* sj)eg.dtarji u5k1c53;i2kmi pjr inant.

ii. Deduce the genotype of the offs:cc/ 1s.:svm q:uknztg8 svr1pring.

Iii. Construct a Punnet grid to show the cross between twspc1+vk wc)p8o offspring plants of the F18pc1c psvk w+) generation.

Iv. Deduce the phenoty 3ounljxo xi2yy-8,c: pic ratio for the offspring of the F1 cross.

7. Amand has a daughter with szd -bqdl/5+ dPadmavathi. Amand is blood group A, Padmavathi is blood group B, and their daughter is blood group O. They are having a second child, a sonq5b d lds-z+d/.
Deduce the probability that their unborn son will be blood group O. Explain your working.

8. Explain how inheritance and environmental factors can interact in a phenoty y-(zyjuhv*j0pe to cause the appearance of human skin couj z*yyj(0 hv-lour.

a. Deduce genotypes for theyy.43c x9ox 6 eo06q)yiyl vd twlu2a( three coat colour phenotypes in these cattle.
Use the symbols $C^W$ for the white coat allele, and $C^R$for red coat allele.

b. Deduce the parental nczv2mcs)e2r4y5 / 9nyj e.*l 9plqzygenotypes of the cow in the image.
Use P for the allele for polled and p for the allele for horns.

c. The roan colour, polled cow in the image is mated wit39at)vyt0vc ()e,owx ng1h 3se9id nrh a white coat, horned b9v ode39tt h(ix,) nar)13g0 ewcsvnyull.
Construct a Punnett square showing all possible phenotypes of the offspring.

10. The pedigree chart shows ABO blood group alleles and their genotykkx/ fq2-ouegj/;z m )pe for nail-patella syndrome, an inherited condition. Thj-o) xg2/m fk/ke ;qzue individuals 1, 3, and 4 in row III are recombinants. Image by D.B. Pylypiv.

Use the pedigree chart to explain the meaning of gene linkage.