A man and a woman have a daughter and a son. Their knx xm3)rw f-/daughter has normal vision, but their son is colourblind. Whim- xr w/fk)3xnch one of these genotypes could be correct for the biological mother?

  Which diagram shows the sex chromosomes ofe xt1 rgt7p jz-rw-:cv)-;c oa a somatic cell in a human male?

  There are two alleles for flower colour in snapdragons. However, the result g2g2( dhk.hq *djycc p21y.heof a cross between two heterozygous plants yielded offspring jqd1ehh. 2yp2y cgh *kg(cd.2with three different observed phenotypes, red, white and pink flowers. Which is the most likely explanation for this observation?

  Which keyword is mattkiz7dv6pf5+ o om5 -cched to the correct definition?

  Which of these statement( g rtim92z//s+zjlf lftn 3(w3r4z mys is a correct definition for a gene?

  The diagram shows a pair of homolon.besie w*1:rgous chromosomes.

How many loci are shown?

  Two individuals, heterozygous for a specph* 2ttghruq e*x(g j83( 9xmrific trait, were crossed in an experiment. Which row shx re( h gj2htxug9q8*mpr *(t3ows the expected phenotypic ratios of the offspring resulting from this cross?

  In some animals, the agouti allele y1vc ;( 8da db:ob:vlucauses individual hairs to have a banded pattern. The non-agouti allele causes hairs to be a single covb :odbu8d lv:c1(y;alour. 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 w-)h3 is ya8k3n37 r7 sarhdv;g v2ppbseed shape in individual pea plants was either round or wrinkled. The results of an experimentawg83 d7 bv3 apsh;iky- 7nvrps)r32hal 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.w j6q42hlw qg4 How many chromosomes are in a fertilised oocyte og j24qw4 whq6lf a fruit fly?

  When does the random orientation of homologous chromosome pairs occ* pttu2+(wxs 4ofx n3cur?

The majority of the genes in the humj u1/atw.7 (ofwb4 lkwan genome have already been mapped, meaning the exact locations of 17fklw (toawwb.j4/ uthe genes on chromosomes are known. The diagram below 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 ofe t l1r9untc5a3e, x:h linked genes?

  The diagram shows a karyogram ol) kxe .-k uqfkbrm5. 4 ci.8i(c4xt4gr2qzzi f a brown male rat (Rattus norvegicus). Which arrow is pointing to a pair of autosomes.c4 -xmrikgx.z t5e4uiqk(q kzf)bi lr.8c2 4 ?

  Mendel observed that there are two possible variations of flower 6k bekmtpgtd1ns: yx3o21 09hcolour in pea plants, purple and white. After a genetic kb oxptkm12 3:dg0h e6n9ts1ycross, 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 birt)dztauh c 8r/)h weight of children born in London in 1991. u8dr ))c/z ath

  Which of these traits is an example of continuoue5y(g o xtmw:c3.:(s qdjnyvz)y f,t)s variation?

  Which row correctly describes diploid and7n j7qhnt wf6 r94v*kf haploid cells in humans?

  The following table shows the diploid chromosomeh/wvm.vl;)se2z o b v9 jd2*zc number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is cauj.v:*r)t++oj(zmk rkb z rk,ssed by 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 n7rps4 8iv1/v1tnl vu blood type A had a child with blood type O. What are the possible gsv1v78un4t /vnplr i 1enotypes of the biological father?

  Which row shows the correct annotatio5w9ns5zpc;tu x,m l 9in of the alleles for blood groups?

  Which of these statements are true fovsp (6h;kz6wf ewab*2r 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 anaaof 5 nwflgb8u)vskk:c .7p/7emia and the spread of malaria across the continent of Africa. fvb7ao)fn/ 78g:su p5wlc.kk


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 (Eqk;ytyw) .sif;uus przewalskii), fur colour is determined by a number of genes. Brown colour (B) is dominant to sandy colour (b) and an ombre (two tone) colour (;.y)ifyt ;wksP) 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 unlinked genzki. *h+lfo/pk 1ymo uz2)2 vjpui-w4es.

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

Sickle cell anaemia is causebhjtlret64 u0f+7q o pt8r w7*d 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 thaxex0 f(6 awug9t is homozygous for brown, long hair and a female0wxexf 9au g6( cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), the h:+ju du9tnl* allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the allele for long seeds (L) is dominant ove* u9lutj+dhn :r 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 porcl g3 qu)tc91i44mi fkgnca6h 8ellus), long hair (L) is dominant to short hair (l), and curly hair (C) is dominant to stri6l)u1 cqgkh gia49mfc38n4taight 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 0b. 1+fke :1r lytd lc.zo:hec*tmrd ks0rt09pedigree chart below?e deo09zks1 m 0+:hltryb.01r.tld* kct: cr f

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

  Which of these statements about genetic disorders is/are cor;wu i,9;yvpq: misf0prect?

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 d-58pte;s eo*kqna/ knormal 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 shown in the p r 4uns4tv*jyvkqm6+1x-e fm2edigree chart is X-linked recessive and not autosomal recessivqyx2 tve *vrk14 mjuf+s4-6mne?

  Different species of living organisms have different numbers of gec(6jfhss :)t hnes characteristic to them. The table shows the estimated number of genes for fivf6(shsjh : )cte 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. Ib82-wa i rqvwas-: yt(f the pea plants Mendel was studying can only be white or purple and follow the rules of Mendelian genetics, which of va:w 8sy- wtrb(-2qi athese statements was correct?

  A biological male with hemophilia and a biological female without xjdri,.) u;wc(;jm)vx;p p jyhemophilia have a daughter without hemophilia. What are th .xj;yxduvr;cpj)(;) jip w,me possible genotypes of the daughter?

  A dihybrid cross was carried out bet p-u77fum9yr- zj rs:q;u)yrdween two sunflower 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 significand:y7)r f9r 7s u-pujyuq mrz;-ce 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 can havvny(*mmr xg/.jz 0sy:e a child with b:nmxy m0v/ z.*yrg(jslood type O.

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

3.Explain the role of inheritance in genetic diseases.