1. Red-green colour blindness is caused by an X-linked recessiveu0jrdxm* /.ze allele. In the pedigree chart below which individuals must be carriers of the red-green colour blindn uz0dmrxe*.j /ess allele?

  2. If the parents in the pedigree chart above had a fourthfpe-7-ena*rc8k - nmp(,) bm nep (zbt child who was female, what would be the probabi(8t enm nceprb, am7f--*e()n kpp-zblity that she was colour blind?

  3. In Labrador dogs, black coat is dominant over chocolate coat. The genotypeal)/zc 1 d.nfa2+: cpdqbr*kg of a black male labrador is unknow. 1fca) :z/cpq da+rb k*gln2dn. How can the genotype of this black Labrador be determined?

  4. Which of the following best defines th qsd01rww / 7x 7-h)cnf,cyb5t,daz ufe term, “gene”?

  5. Phenylketonuria (PKU) is an inherited ax twu kj06e(/-bgt)thuman 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 a non-functionttkgtuxj-eaw6(/ b 0) al 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, yv/.0i t 6wov o73ulwgmellow or green, is dominant.

ii. Deduce the genotype of thezf7 t;riey,3gq*e- gz offspring.

Iii. Construct a Punnet +* xa:aab2.g bn*vk *ofq5j cnwwse:(grid to show the cross between two offspring plants of the F1 generationeaa.jk *:ng b2w+ fnx5:av bc*qs wo(*.

Iv. Deduce the phenotypi6 -ktj v xhn c7d7nza x/x,mtv5oef36s)k.th .c ratio for the offspring of the F1 cross.

7. Amand has a daughter with Padmavathi. Amand is blood:yo (g5mhawf 0beep21 group A, Padmavathi is blood group B, and their daughter is blood group O. They are having a secondygf (:b1hw am2ep0e 5o child, a son.
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 phenotyhvrl5*7rx/mc-p +x2 jhg.velpe to cause t/ 7+xvl5rcxl e2 r.mhgph*v-jhe appearance of human skin colour.

a. Deduce genotypes for the three coat colour phenotypes in p:hoinsl knm* 3. io6n:ku( 5ethese 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 cok gq2z*p4pi c6w 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 image1i69r dk8j*ktlh ne (1 kjjr-q is mated with a white coat, horned bull.jkrjk * n(9-rh8qje t1 k1l6id
Construct a Punnett square showing all possible phenotypes of the offspring.

10. The pedigree chart shows ABO blood group allelesy7jyroao ux*4r5xf )7dg6w q8c6 )qco and their genotype for nail-patella syndrome, an inherited condition. The individuals 1, 3, u* r4acw q8o 7qjfco56dryx)7 g 6x)yoand 4 in row III are recombinants. Image by D.B. Pylypiv.

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