A man and a woman have a daughter and a son. Their daughter h( b6jd2ylxacc8 ovs 85as normal vision, but cj 88x(yol6 5dbsc2va their son is colourblind. Which one of these genotypes could be correct for the biological mother?

  Which diagram shows the sex chromosomes of a . /(o4eoybi 6t,t6oqm x23b*ghhq pm rsomatic cell in a human male?

  There are two alleles ,jq;w4ckz gc4for flower colour in snapdragons. However, the result of a cross between two heterozygous plants yielded offspring ;qc4 c,k4g zwjwith three different observed phenotypes, red, white and pink flowers. Which is the most likely explanation for this observation?

  Which keyword is matched to the r,i5jqr3sykwj -3zkl :sw :5jcorrect definition?

  Which of these statements is a correct definition for a g6h-wyi nes;823dzegh ene?

  The diagram shows a pair of homologou- k:u8 ap3 i,ndb8jrq4o6te cfs chromosomes.

How many loci are shown?

  Two individuals, heterozygous for a s-hwd.uxl/aq(g3)s-mol e ofg. r. ; zdpecific trait, were crossed in an experiment. Which row shows the expected phenotypic ratios of the offsprio.d xs wgruf)(l.al .- zg;qmoh -3/deng resulting from this cross?

  In some animals, the agouti allele ca 4e9 /(qau .vbjogrbb0uses individual hairs 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 pr/9uabbb vjoeq.(0g 4attern.

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

  Mendel observed that the seed shape+bq8 ivz/sk*2c boj +k in individual pea plants was either round or wrinkled. The results of an experimental cross yielded 315 offspring with round seeds and 1+i/ j+ czk* skbo8vq2b05 offspring with wrinkled seeds.

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

  Neurons of the fruit fbh:)24zvp9o1p nk yw wc7kyyp0) a az)ly (Drosophila melanogaster) have 8 chromosomes. How many chromosomes are in a fertiz79 c)oa wyk)ph y2 ya:0z4p)kp1bwn vlised oocyte of a fruit fly?

  When does the random oljz 0md.sxo 2z -/5whu y2rz(grientation of homologous chromosome pairs occur?

The majority of the gel6a9j+p.q+kun wpxp t,a ehmr7. o0sj+:n8wgnes in the human genome have already been mapped, meaning the exact locations of the genes on chromosomes are known. The diagram below shows one representation of a jkw:07,p ugp+hsa9jxqo8 n. plwre+n .tm6a+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 ofrnlbzv 5-. bq: linked genes?

  The diagram shows a karyogram of a brown male rat (Rattus norvegicusugpud1hvj;fq2/7f 1b6mjaq v 0zau 5 3). Which arrow 2 u vzu 71qq0pgf6v/fu513dm bj j;haais pointing to a pair of autosomes?

  Mendel observed that there are two possible variations aa28.f:fxu p.gx 4tcdof flower colour in pea plants, purple and white. After a genetic cross, the ratio of plants with purple flowers to white flowers is 1:1. What were the genotypes of tpxf.24a.x8tu cafg :dhe parents?

  The graph shows the frequency of birth weight of children born in Lokv80.bkxm 45e8(2l djyhvaj lndon in 1991. m40kx ha2 (8.vljevbdy8k5 lj

  Which of these traits is an example of continuous variation0o*fn d tz;/cu?

  Which row correctly describes m, . 0-m*hfmmcmb c,r gll(dzr) xgf11diploid and haploid cells in humans?

  The following table shows the diploid chromosome number of a range of speciew ; et;o0zy)xg sql+;ds.

Which of these statements is correct?

  Sickle cell anaemia is caused by8lt j l1g t494mpbwx:b 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 a child with b hs;swa+p 4olk ou6+g4lood type O. What are the poupl+ a4h ks6o;s 4+gwossible genotypes of the biological father?

  Which row shows the correct annotat 9yuwkk3x94zuxs24 :jj x/fe bion of the alleles for blood groups?

  Which of these statementcyirg (ln*tz+ts,9m1s 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 spree*ma-euxb 5c9n cy/+n dl l;aa8jc6;pad of malaria across the contlaudj*aen m /cc;5c pn-+986y x; labeinent of Africa.


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), fuom :c6 npfp*/c5ytzf,r colour is determined by a number of genes. Brown coloun:m*,fo/tpcyc z6 p5f r (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 linked unbryu/d/:s1 ad jkeb2z3 6t:and unlinked genes.

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

Sickle cell anaemia is causedk7 a hz/)zjtm7 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 betweb,p rnav72 p2hen a male cat that is homozygous for brown, long hair and a female cat that ha2vp ,hp7 anb2rs black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum o8 7h:eetv cx-m5 rao+rfficinale), the allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and tv87aherrme + x:- ct5ohe allele for long seeds (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 (L) is dominant to f yy9)k txl.t4short hair (l), and curly hair (C) is dominant to straiy) kt4xtl.f9 yght 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) 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 condition shown in the pedigree ch f:3csrje y*8o)hlwrd m2f/( jart b8*f/ hf y(m dcs ljre):wrj23oelow?

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

  Which of these statements about genetic disorddedi1ivk* - (sers 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 caniva7dml( cq 6gz62a0v show 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 in xx2)l wq- p9qgveaa1s3t z:f;heritance of the disorder shown in the pedigree chart is-p:atw2 9 lf1g ;xvzse)qa3qx X-linked recessive and not autosomal recessive?

  Different species of living organisms have different numbers of zbv3 zqzj) .d 0k.4armgenes characteristic to them. The table shows the estqjz)armk40d.bz vz3. imated 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 -yyee,y zz)5yisvr- :j;-m nauc 55zqplants, including flower colour. If the pea plants Mendel was studying can only be white or purple and follow the rules of Mendelian genetics, which of these statements was cecv5ne) -;m:5-a y,qj-uzzy yris5zyorrect?

  A biological male with hemophilia ;l2 mi4e-u*o1rav f-i4sljfmsgzy tg+o /( +e and a biological female without hemophilia have a daughter without hemophilia. What are the possible genotypes of the d+4g 1gmfslzo m;yjs r fo2eaei +lvi-*(-4u/taughter?

  A dihybrid cross was carried out between two sunflower plantse 9i75nmnr:vg (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-squared test was 10.05; what does this ing9e5mr nv7n:i dicate?

1.Explain how parents with b650uyjc- qnvm( kn hr/lood type A and blood type B can have a child with blood typ/ q-6k ny5nch0jumvr( e O.

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

3.Explain the role of inheritance in genetic diseases.