A man and a woman have yn3-f qj.vlp1c-q u/2wdc zm-/vd-yha daughter and a son. Their daughter has normal vision, but their son is comzd.qy 2hjv y-/lwfqvpn/1- - cc-d3ulourblind. Which one of these genotypes could be correct for the biological mother?

  Which diagram shows the sex chromosomes of a somatic cel nb:*necg au:;l in a human male?

  There are two alleles for flowexa,+bmne dqhx( -,v,g r colour in snapdragons. However, the result of a cross between two heterozygous plants yielded offspring with three different observed phenotypes, red, white and pink flowers. Which is the most likely explanation for thisx, ,xnh+v eda-(qb ,mg observation?

  Which keyword is matcheqsih ymqe,r+ ;mf r9nw1 3 39)yxs/qiud to the correct definition?

  Which of these statements is a correct definition fo6gsh j 8xa(+hcr a gene?

  The diagram shows a pair 5 6w)lkux9 tj0,:imqw gcf,gcof homologous chromosomes.

How many loci are shown?

  Two individuals, heterozygous for a specific trait, wea 886pygyhzk 8re crossed in an experiment. Which row shows the expected phenotypic ratios of the offspring resultinzy8 ayg68hk8 pg from this cross?

  In some animals, the agouti afjv5w - ensql3+tw70v 3s i-osllele causes individual hairs to have a banded pattern. The non-agouti wqo0 s+ n3w3ei--7stls5 vv jfallele causes hairs to be a single colour. Individuals who are heterozygous have hairs with a banded pattern.

Which combination of parent genotypes would allow for production of offspring that do not have the agouti characteristic?

  Mendel observed that the seed shape in individu8mj)9h et lt* snzi 3h mhi(26lgkw(f4al pea plants was either round or wrinkled. The results of an experimental cross yielded 315 offspring with round seeds and 105 oijkhm8wi(l h 2)mtn64 lfse* zt(gh39 ffspring with wrinkled seeds.

Which row in the table below states the most likely genotypes of the parents?

  Neurons of the fruit fly (Drosophilf09c,bj/wql cba edpr94x7 2 pa melanogaster) have 8 chromosomes. How many chromo,l jc97 pxq f2p9bbdre c/04awsomes are in a fertilised oocyte of a fruit fly?

  When does the random orientation of homologous chromosome pairs om*wa+a aa-s(gn9 pnu7ccur?

The majority of the genes in the human genome have already been mapped, meani* .7menz( 9odo hso4ling the exact locations of the genes on chromosomes are known. The diagram belowo74z *ohi mso9.dln( e shows one representation of a homologous pair of chromosomes.

1.Define locus.

2.Identify the number of loci shown in the diagram.

3.Distinguish between gene, allele, and locus.

  Which is the correct definition of linr+avhs9qi2on - 7t-fack oon i.xp2xb+0+dn0ked genes?

  The diagram shows a karyogramzjzj,sq )(un o 8 4j1nfz:hcq, of a brown male rat (Rattus norvegicus). Which arrow is pointing to a pair of autos:z o qn,) 1hs(zjj8ujz,cnq4fomes?

  Mendel observed that there are two u p kg-fe4gw(: owdy;-possible variations of flower colour in pea plants, purple and white. After a genetic cross, the ratio of plants with purple flowers to white wo gyd;p wfe(:-g4- ukflowers is 1:1. What were the genotypes of the parents?

  The graph shows the frequency of birth weight of children born in Lotkhq:v 6:l, 1(zvjjcvndon in 1991.,:zc6vv (hv lk: jj1tq

  Which of these traits is an examplezwt+kuw0 ( i5y of continuous variation?

  Which row correctly describes diploid and haploid cellagxg; )+ca jxn:x-:ldu/ a0qfs in humans?

  The following table s(viv5-iidf:zl9a6 kie p a+3uhows the diploid chromosome number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recessi0 ttiik:o o lj7t(v(/ave allele (Hb$^S$). The dominant allele is Hb$^A$. This image shows the inheritance of sickle cell anaemia in a family.

What are the genotypes for individuals 1 and 7?

  A biological female with blood type A had a chvvd:cl rxj;cr/5 bc xxi:y-56ild with blood type O. What are the possible yv-5 rl x:;dr6/jcxbcxv5: ci genotypes of the biological father?

  Which row shows the correct annotatioj:4(cvhog i1g n of the alleles for blood groups?

  Which of these statemsc s v; sg4o*7mvo.z/hents are true for alleles?
I. Alleles are versions of a gene
II. Alleles differ by one or more base
III. Alleles affect the same characteristic

The maps show the incidence of sickle cell anaemia and the kz *rkny07q a,-n3iws-(w cre spread of malaria across the continent of Africa. cn qka zn3re ,-yiks(7-w0rw*


The graph shows the average density of malarial parasites present in the blood of Hb AA (not affected by sickle cell anaemia) and Hb AS (carriers of sickle cell anaemia) people in Sub-Saharan Africa.

1.Compare and contrast between the distribution of sickle cell trait and malaria in Africa.

2.1.State the mode of inheritance of sickle cell anaemia.

2.2.Using a genetic diagram, determine the probability of a child having sickle cell anaemia, if both their parents are carriers of the disease.

3.Blood samples were taken from children to create the graph. Suggest one difference between the appearance of blood cells in Hb AA and Hb AS samples.

4.State at which age there is the largest difference between the number of parasites found in the blood of Hb AA and Hb AS samples.

5.Suggest one difficulty of collecting sufficient data for this study.

6.Using your own knowledge and the data provided, discuss whether carrying the sickle cell allele offers protection from malaria.

In Mongolian horses (Equus przewalskii), fur colour ishb )g ) 5e6ytg ukyh4*6+ouqrp determined by a number of genes. Brownok+ u5uhbg)t6 *64yqgpey hr) colour (B) is dominant to sandy colour (b) and an ombre (two tone) colour (P) is dominant to one tone (p).


1.A homozygous sandy ombre male horse is crossed with a heterozygous horse for both traits. Draw a Punnett square to show the potential results of this cross.

2.Identify the possible genotype recombinations, after fertilisation, from the cross in part (a).

3.In pigs, the curly tail is dominant to the straight tail, and pink skin is dominant to black skin. On a pig farm, the resulting phenotypes from double-heteroygous genotype breeding were recorded. The chi-square value for the phenotypes of the offspring was calculated and the result was 340.6.
The table below shows the degrees of freedom (D.f.) and critical values at a significance level (p) of 0.05 (5%) for a chi-squared test.
Discuss whether the genes for skin colour and tail shape in pigs are linked or unlinked.

1.Distinguish betweenx hvw9m0 vj v01uly5y6 linked and unlinked genes.

2.Coat colour is a polygenic trait. State the meaning of polygenic.

Sickle cell anaemia is cauh4j8 wfa.6r 0l0hhe 1n4yuivr sed by the allele Hb$^S$ . The normal allele is Hb$^A^ .

1.Identify the genotype of individuals 1 and 2.

2.Predict the probability of individuals 5 and 6 having another child that is unaffected. Justify your answer.

3.If individual 7 had a child with an affected biolgical female, identify the possible genotypes of the child. Justify your answer.

4.Deduce, with evidence, the pattern of inheritance of sickle cell anaemia that is shown in this pedigree chart.

5.Distinguish between sex-linked inheritance and autosomal inheritance in humans.

  The diagram below shows a cross between a male cat that is homozygous for wr ;8cs0xo3 ifbrown, long hair and a fem w3i8s 0fxc;orale cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), the allele for di:fu h0zo3kzq 58zu8tvamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the allele for long s5:zu0f 88ozkqu3z vh teeds (L) is dominant over short seeds (l).

In a genetic cross between a dandelion that is heterozygous for both traits and a dandelion that is homozygous recessive for both traits, what would be the expected proportion of long seeds?

In guinea pigs (Cavia porcellus), long hair ui3bcu6zgo b),k7f2v (L) is dominant to short hair (l), and curly hair (C) is dominant to straight hair (c). A test cross was carrieg 2cu uzb76),kbf3ovid out between male heterozygous long, curly-haired guinea pigs and female short, straight-haired guinea pigs and a chi-squared test (χ2) was carried out on the offspring.



1.1.Using a genetic diagram, state the expected ratio of the cross between the two parents.

1.2.Identify the recombinants.

2.1.Calculate the ratio of the observed phenotypes.

2.2.Suggest a reason for the difference between the expected and observed ratios.

3.1.State the null hypothesis in this study.

3.2.Deduce with reasons whether the null hypothesis should be accepted.

  What best describes the inheritance of the c. mn7 gkcu-yq3w:2b vbondition shown in the pedigree chart belb-wuq32v:yn7 gmbk c. ow?

I. Sex-linked trait
II. Dominant trait
III. Recessive trait

  Which of these statements about genetic diso9ytxxaai y;jqv88zw(rgbj zw z9:-;,rders is/are correct?

I. The majority of genetic disorders are caused by recessive alleles.
II. Genetic disorders can be sex-linked.
III. Offspring of two parents with the same genetic disease will always be affected.

1.Outline how polygenic traits can s;0o h,k l1zs 6k1kasfkhow a normal distribution.

2.Outline the differences and similarities between homologous chromosomes.

3.Explain why expected and observed Mendelian ratios may differ.

  What suggests that the inheri+x,y pssz f8y1tance of the disorder shown in the pedigree chart is X-linked recessive and not autosomal reces ysx1p+ ,zfsy8sive?

  Different species of liviny+5vr +bck 6d5oe gsl7g organisms have different numbers of genes characteristic to them. The table shows the estimated number of genes for five5g ovlb75e+6 kcdyr s+ species.
Species Estimated number of genes
Escherichia coli (bacteria species) 4,000
Drosophila melanogaster (fruit fly) 13,000
Canis lupis familiaris (dog) 20,000
Homo sapiens (humans) 30,000
Oryza sativa (rice) 40,000
1.Using the information in the table deduce the estimated number of loci in a human genome.
Estimated number of loci in a human is   .
2.Explain how a mutation can affect a characteristic.

  Mendel studied eight characteristics ofjpq1(z1txys . pea plants, including flower colour. If the pea plants Mendel was studying c.qj 1ytsz(px1an only be white or purple and follow the rules of Mendelian genetics, which of these statements was correct?

  A biological male with hemophilia and a biological female without hemophilia h(ubccdsd nr) l9+n* ,fave a daughter without hemophilia. W(n+lcu 9 fb*, nc)rdsdhat are the possible genotypes of the daughter?

  A dihybrid cross was carried out between two sunflower plaxc ex4q19z, dk7 b* 7/xtokmswffh*v5nts (Helianthus annuus) to see if the genes for seed number and seed shape are linked. Thtxhv sk71 f mw/ 7eq*d5xo 4z9k*,bxcfe critical value for the chi-squared test at the 0.05 significance level was 7.82. The calculated value for the chi-squared test was 10.05; what does this indicate?

1.Explain how parents with blood type A and blood type B cal-, k ivj j9s ia;t3akee134cn5 yexb*n have a child with blood type 5kck *xt31 sjb i4ve9j,ae -elia; 3ynO.

2.Outline how polygenic traits can show a normal distribution.

3.Explain the role of inheritance in genetic diseases.