A man and a woman have a daughter and a son. Their daugh ,v wkq- 4fgaf9e2x.zcter has normal vision, but their son is colourblinwf9.fk2ve-ax q,zc4g d. Which one of these genotypes could be correct for the biological mother?

  Which diagram shows the sex cgb w*r2a9l, athromosomes of a somatic cell in a human male?

  There are two alleles for flower colour in snapdrawah*s3jv)d a; gons. However, the result of a cross between two heterozygous plants yielded offspring with three different observed phenotypes, red, white and pink flowers.jw3h avs *da;) Which is the most likely explanation for this observation?

  Which keyword is matched to thex 8r pk015mhd9)jwwyt correct definition?

  Which of these statements is a correct definition for ap b 5xs*tabn6ds;i;hpw, jk 28 gene?

  The diagram shows a pair of homologous chromoso /nxdun x-+m b,+t1asfmes.

How many loci are shown?

  Two individuals, heterozy:bayp.vmgu4* z)us u 0gous for a specific trait, were crossed in an experiment. Which row shows the expected phenotypic ratios of the offspring resulting from thi4 vua .symgu0*ub)p z:s cross?

  In some animals, the agouti allele causes individual hairs to have a 0(fvcscib4 )i(n8h zk banded pattern. The non-agouti allele causes hairs to be a single colour. Individuals who are heterozygous have hairs with a banded p)i0c n( fcikb vhzs8(4attern.

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

  Mendel observed that the seed syq9:wakcub6v/2rhx* .h gh5w*e: ugahape in individual pea plants was either round or wrinkled. The results of an experimental9k*ba. vrq: h xyu2a6 /hw*euh:gwg5c 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 meli1e(wrrsb 9rd)iw:c h*sehe h )8y8h4anogaster) have 8 chromosomes. How many chromosomes are in a fertilise )9hh ersh8wercw18 i*: sde )4hry(ibd oocyte of a fruit fly?

  When does the random orientation of homologouay rqw:9qoe ( ,f;qv;21ttjjqs chromosome pairs occur?

The majority of the gd:64me: f1oe) c( :yot qijalaenes in the human genome have already been mapped, meaning the exact locations of the genes on chromosomes are known. The diagram below shows one represen:ma lijye et6:( a)dco:4 fqo1tation 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 defi/ rk 1v1/cn7bt2got4ryd k;,tazxps4nition of linked genes?

  The diagram shows a karyogram of a 7ic.4oqf- (hyfe7 emu brown male rat (Rattus norvegicus). Which arrow is pointing to a pair of autosomes? 7 e 4yqc.fi u(ehm-f7o

  Mendel observed that th1z fths(.em:wy uln5* ere are two possible variations of flower colour in pea plants, purple and white. After a geneh *w n:zm.fe( l5ty1ustic cross, 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 weigr5 m3/eundet*q ui ,pc/gn q/8ht of children born in London in 1991qp 8,u/n/ dti5gr3 eqmce/n*u.

  Which of these traits is an example of continuous3/xat- 8ve6 icls xlg. variation?

  Which row correctly describes diploid dnef ;-)qw(3d1 kpggsand haploid cells in humans?

  The following table shows the diploid chromosome number of a range qefo9o,i r) pf 6(;xvkof species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recessive allel 5 ari xyi5+0e.vo6otre (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 2 + ldo+ jr.bh5db8cazA had a child with blood type O. What are the possible genotypes of the b5 bjd .a +8dcr+bhozl2iological father?

  Which row shows the correct annotation ofvrc bge3bsa ;)y uz*)0q:9-u*tfbfyle2qzp( the alleles for blood groups?

  Which of these statements are true for allef4f d1q15z+tgxinm 8bles?
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 incidenc. ys9r.s*rz6ruqf0efr -;ygx i1 cr.ze of sickle cell anaemia and the spread of malaria across the continent of Au.ie .0 r rzqz;.1 sryrf9y fg*6rs-cxfrica.


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 pn8vmu4txo t ,p7j- *wdrzewalskii), fur colour is determined by a number of genes. Brown colour (B) is dominant to sandy colour (b) and an ombre (two47pt-nw,xv 8toj*um d 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 and unlink:)* fqnep b4leglw70jyvqz .9 ed genes.

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

Sickle cell anaemia i 0txx51;cv: liuo8qc. 1rvzdks caused 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 tdj06)v*t2 u/l8tlkspw n9uubetween a male cat that is homozygous for brown,du l 6lvp/j t8u2*)k0 u9snwtt long hair and a female cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), wqcbz 7k- qhp/ zyv975 um))uythe allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the allele for long seeds (L) is dominant over short seeds (l).)qy / )y 5zpu7vu bz9kw7q-hcm

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 dominan5fo0e we.lwu4rs9t u4t to short hair (l), and curly hair (C) is dominant to straigh u9orfe40ww .eu45tl st 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+nvbtxu2.b qg; rt a /8a2qz.t pedigree chart belowr qu+8vtx 2ag2ntzab. /q.;tb?

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

  Which of these statements about genetic disorders is/are coft/qa,3io . xvrrect?

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 nys mwp53c/t meto :9h6ormal distribution.

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 sho 9),fpivjju 9lwn in the pedigree chart is X-linked recessive and not autosomal recess vp9)filju 9,jive?

  Different species of living f*r- 8uox:s4jf3 hw xjorganisms have different numbers of genes characteristic to them. The table shows the j-4x8 r3hfwouxjfs:* 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. If9 ;q-co ndj2t)(ll dck the pea plants Mendel was studying can only be white or purple and follow the rules of Mendelian genetiltdc oj-2;kcd( q) 9lncs, which of these statements was correct?

  A biological male with hemophilia and a biological female b+-+ap vnw35ffz6re d without hemophilia have a daughter without hemophilia. What are the possible g-zfn pedbf+v+6aw 3r 5enotypes of the daughter?

  A dihybrid cross was carried out between two sunflower plants (Heliao) h4zu*u5kqf nthus 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 tes5*z)h4ku q ouft was 10.05; what does this indicate?

1.Explain how parents with blood type A and blood 800jkewlu t (jtype B can have a child with blood type O. j8w 00l uej(kt

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

3.Explain the role of inheritance in genetic diseases.