1. Red-green colour blindness is caf w:x63jq wlwesul*p7 ,q3bgeh1h 7n 0used by an X-linked recessive allele. In the pedigree chart below which individuals must bejnpw 1lefb*hs7lwwh 330g,:eq 6q7 ux carriers of the red-green colour blindness allele?

  2. If the parents in the pedigree chart above had a9jz. nemk;eig u (0hpd 3dkp69 fourth child who was female, what would be thed p3;ze0 u6p .9kjkimn9d (ghe probability that she was colour blind?

  3. In Labrador dogs, black coat is dominant co0xclc6)lc ax q(n.* over chocolate coat. The genotype of a black male labrador xlcl*acxnc 6o. c(0) qis unknown. How can the genotype of this black Labrador be determined?

  4. Which of the following best defines the tern ; 58/hbcg vo 2h2uwyvg0x*c,fm;vikm, “gene”?

  5. Phenylketonuria (PKU) is an inherited human disease caused by anbz 2(z/sm w;b recessive autosomal allele in a gene which codes for an enzyme needed to convert phenylalanine to tyrosine. The PKU allele produces abms2; wbzn( /z 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;0swfna*nuiwe. h qisv9 1 3 k()ribbekk05;p the alleles, yellow or green, is dominant.

ii. Deduce the genotype of the offsprin t1,k s3rem9bwn.u)tjg.

Iii. Construct a Punnet grid to sho 8qxg6vphu9 ho c oh0ay5)8(vpc eru-8w the cross between two offspring plants of the F1 generati6 avo8- vc)phe8 0uquo(8pyc5r9hxghon.

Iv. Deduce the phenotypicy-k ud7 :7y2et go asv).w2xci ratio for the offspring of the F1 cross.

7. Amand has a daughte3 gtz:g cpo0z0 9ws:ddr with Padmavathi. Amand is blood group A, Padmavathi is blood group B, and their dao:zw :0ds3g dcg0tp9zughter is blood group O. They are having a second child, a son.
Deduce the probability that their unborn son will be blood group O. Explain your working.

8. Explain how inheritance and environment7k))n j aje j tpv3jsz(t.my+-al factors can interact in a phenotype to cause the appearance of human skin enptv. j-jmsaz+7tjj3 )yk( ) colour.

a. Deduce genotypes for the three coat *2m/v1/ fovz/oyyh;)idxw i xcolour 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 genotypes of the co.ndyh* u ozk;dex: 7vl-o9 e-fw 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 with a white coat,f ,ke+pov 9b2z1l4rm q; me8ju horned bulpj b4,e1lkmvq8mfz;e +9 2roul.
Construct a Punnett square showing all possible phenotypes of the offspring.

10. The pedigree chart shows ABO blooldch g-;i51mx d group alleles and their genotype for nail-patella syndrome, an inherited condition. The individuals 1, 3, and 4 in row III icg;dhxm1 -l 5are recombinants. Image by D.B. Pylypiv.

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