A man and a woman harkl5 .pvw8at rlauf.- ./2wlkh1iw- kve a daughter and a son. Their daughter has normal vision, but their son is colourblind. Which owr-lk5/l -.k8wilt krvpafuw1 2ah..ne of these genotypes could be correct for the biological mother?

  Which diagram shows the sex chromosomes of a s8amlj/fhs ;,.e zfzj)u1w3,tougv vhw ;d65 b omatic cell in a human male?

  There are two alleles for flower colour i zo:6r)s*r; 0js4p qrgj7fiez n snapdragons. However, the result of a cross betwees4jrs*0ej7r: p6;ofgz) rziq n two heterozygous plants yielded offspring with three different observed phenotypes, red, white and pink flowers. Which is the most likely explanation for this observation?

  Which keyword is matched to the correctdafvg .pp;jl7p* +8qw5 1pjr g definition?

  Which of these statements is a correct definition for a gjflo)z( i33 3cizb/fnene?

  The diagram shows a pair of homologous chromqitb 2eb-v0d- osomes.

How many loci are shown?

  Two individuals, heterozygous for a specific trait, were crossed in an expe0g.chc+yu. awx zpe79 riment. Which row shows the expected phenotypic ratios of the offspring resulting from this pcg u.c+a.9zwhx y 70ecross?

  In some animals, the agouti allele causes individual 89auzbtrnc(dgcchy 2* (kj99hairs to have a banded pattern. The non-agouti allele causes hairs to be a single colour. Individuals who are heterozygous have hairs with a banded pattern. zbuc8g(2y 9r* (9ha jtd9c ckn

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 individual pea o e- oh+rv8;iz,mkybx bjwar8(y,i gq )z3 .d-plants was either round or wrinkled. The resj ,h(yg+akx,v;iw88rri bo-z-d ebqo.3) myzults of an experimental cross yielded 315 offspring with round seeds and 105 offspring with wrinkled seeds.

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

  Neurons of the fruit fly (Drosophila melanogaster) have 8 chromosomes. How mogh;hxm8 8c5.wv y8whany chromosomes are in a fertch8xywhmw. ;ohv g885ilised oocyte of a fruit fly?

  When does the random orieb 2ynz1 hp6pu 1jy :b7+o9 r+*yhxuyqvntation of homologous chromosome pairs occur?

The majority of the genes in the human genome hwv rx g9syz:v;leay) 9dkc2 (3ave already been mapped, meaning the exact locations of the genes on chromosomes are known. The diagram below shows one represe; 9 xcg3)szd 2r vyvywkl9(a:entation 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 nu6 f gufy50s1definition of linked genes?

  The diagram shows a karyogram of a brown male rat (Rattus norveg(xqr :: wtqi(zicus). Which arrow is point: zx((qtqiwr: ing to a pair of autosomes?

  Mendel observed that there are two possible variations o,fgm fmze 69(yf flower colour in pea plants, purple and white. After a genetic cross,myf megz,f (69 the ratio of plants with purple flowers to white flowers is 1:1. What were the genotypes of the parents?

  The graph shows the frequency of birth weight of children born in Londoz-*thw +fb 20lg/ep skiu. uw5n in 1991.pw*2skwi5lb0zue / .guht+ f-

  Which of these traite8nweundcx 8rp 2me:: 9p h+f)s is an example of continuous variation?

  Which row correctly des bruj-(pa9s64/r0u n2tve3 cmdk+ dnbcribes diploid and haploid cells in humans?

  The following table shokq1k k g4if4muqw(7/ jws the diploid chromosome number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused b4imqx jt5qwjbd /9u3; y a recessive 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 i0,rv6 bn. jzpa child with blood type O. What are the possible genotypes of the birzp in,0jbv 6.ological father?

  Which row shows the correct 1y k-6ot( gfvgn pf :f4v8b/olannotation of the alleles for blood groups?

  Which of these statements are true for allelejz(aqp 1jv- ,hs?
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 sickl 92w2+b2vjr0d/ic t(dwo rjj de cell anaemia and the spread of malaria across the continent of Afriij2 d2ojcr0j t9drw2+(d/b wv ca.


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 is degkrwl1d/hpt/ e( sn/ay d06r5 termined by a number of gena/1srphrn5 gdew6lk(0 / ty /des. Brown 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 between l 8xm(/cv5sb fu:uy;bn inked and unlinked genes.

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

Sickle cell anaemia is caused bpxnry.4zb5 / dy 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 thatb5o3a 1 y9t,x yncgzt r00gxm* is homozygous for brown, long hair zxg3g*t a5r ,xto9m01 ny0 ybcand a female cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum offic5 1.iv jo9zfof ipy9m0inale), the allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the allele for long seeds (L) is dominant 5f1iv9 jyizm p90o.ofover 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 t.jjh *q0cbwkl0 *;sb(L) is dominant to short hair (l), and curly hair (C) is dominant to straight hair (c). A test cross was carried out between male heterozygous long, curly-haired guinea pigs and female short, straight-haired guinea pigs and a chi-squared test (χ2) w cqs;jl j0thb*wb.k*0as 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 ofqobp c5*e 2vu7 the condition shown in the pedigree chart beluecpov q*b5 72ow?

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

  Which of these statemen 2zwvqed kk0pef(p)u*d7x ) x-ts about genetic disorders 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 show a normal distribvtq.2 cns o0+ rpa3s,jution.

2.Outline the differences and similarities between homologous chromosomes.

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

  What suggests that the inheritance of the disorder shown in the pedigr +)tbwl5nr- t/ 6fhoyeee chart is X-linfet)5o+h/ly - wbt6nrked recessive and not autosomal recessive?

  Different species of living organisms have different numbers of genes charapel+ yl00e+ia:a 7iitl 0tq*r cteristic 0yarqi*7tli0 t aie lep0++l :to them. The table shows the estimated number of genes for five 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 of pea plants, including flower colour. If8sxtiw)9du8 t ,uo w3y-nq m;6p s(kt pou.x-h the pea plants Mendel was studying can only be white or purple and follow the rules of Mende t-kus(wwi;.xd8,h oxqpt-6m8 yuto pnu3 9) slian genetics, which of these statements was correct?

  A biological male with hemophilia and a biological female without hemophil,c)im,x nra3z ia have a daughter without hemophilia. What are the possiblecxai r,z3m ,)n genotypes of the daughter?

  A dihybrid cross was carried out between two sunf* (wqejw+ gsx/lower plants (Helianthus annuus) to see if the genes for seed number and seed shape are linked. The critical value for the chi-squared test at the 0.05 significance level was 7.82. The calculated value for the chi-s+es xw*/gq( wjquared test was 10.05; what does this indicate?

1.Explain how parents with blood type A and blood type Baekvgc ya01-) can have a child with blooa0g e)1 -aykvcd type O.

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

3.Explain the role of inheritance in genetic diseases.