A man and a woman have a daughter and a son. Their daughterq uhwovd1+ .a- has normal vision, but their son is colourblind. Which one of these genotypes co - 1dvawu+oqh.uld be correct for the biological mother?

  Which diagram shows the sex chromosomb5u av,/ i3(tfvoe ew7+d k0hees of a somatic cell in a human male?

  There are two alleles for flower colour in snapdragons. However, the result of/i4 (q9kmwpqg a cross between two heterozygous plants yielded offspring with three different observed phenotypes, red, white and pink flowers. Which is the most likely explanation fog(mq9k qp/wi4r this observation?

  Which keyword is matched to the correct definxv9; ta .kpjoxw;uxjb 0h)- d0ition?

  Which of these statements is a correct dau1l7ez7xbka ale 7 mrpn; gu/t-/t;-efinition for a gene?

  The diagram shows a pair of homologous chromosomes.unvg(wir ( +ymzi0 )5x

How many loci are shown?

  Two individuals, heterozygous for a specific trait, were crosd,8dxt6 .-wbnfg4 r6)m hmsul sed in an experiment. Which row sw h sut d)m.rnmx6df8, lb6-g4hows the expected phenotypic ratios of the offspring resulting from this cross?

  In some animals, the agouti allele causes individual haiz+9 v 4p men+ytke:)vgrs to have a banded pattern. The non-agouti allele causes hairs to be a single colour. Individuals who are heterozygous have hairn ):vztpvy49+kg+ em es 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 sc0rsta x;0, 5uq5a gn4ao a-jrhape in individual pea plants was either round or wrinkled. The resqa0aar c-s0jr ,gt5;4a ux5noults 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,zxro d*s;b; o many chromosomes are i*orsd x, z;o;bn a fertilised oocyte of a fruit fly?

  When does the random orientation u6-x olko *f d9 r;wsfq+jx1l.of homologous chromosome pairs occur?

The majority of the genes in the human genome have alreuxmc: 87xqq gr jym426ady been mapped, meaning the8uxy:cg6m2q4j 7 mqrx exact locations of the 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 dpoebu ru)6i*wc2x5 j5a z*b 1fefinition of linked genes?

  The diagram shows a karyogram of a brown male r5e,e +lkfntdfe+q6 7t+gm x v5at (Rattus norvegicus). Which arrow is pointing to a pair off+gd k ex6m7 ee ln+vq,+55ttf autosomes?

  Mendel observed that there are two possible v(-- hrznk37 vkkuy f-variations of 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 the parentsr(vn3fyk --7kuhk -z v?

  The graph shows the frequency of birth weight of children born inptx j ib2n,r:jtc.z46sso ,gr 0)(bmn London in 1991. srb nmt0 ij)cpnbo:2,tzx(r. j ,s46g

  Which of these traits is anl* p st*ud2yy+ example of continuous variation?

  Which row correctly describe(5w i45xakew os diploid and haploid cells in humans?

  The following table shows the diploid chromosome numb6va- , 5ntpbjver of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a re5yg cozm5)3b/tr b3iz cessive 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 w bb;4 l3iutnb:ith blood type O. What are the po;4tub: 3bb lnissible genotypes of the biological father?

  Which row shows the co 3ba6ocz4p8bi rrect annotation of the alleles for blood groups?

  Which of these statements are true for allele4l+)9hlv:t q:utk6sy d rywn/ s?
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 spread of mala8jho 5c yfi:m4ria across the continent of Africa.j: f5mhci84 oy


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 de; im/apr7 nyuod)9ikx 1z8ay0termined by a number of genes. Brown colour (B) is dominant to sandy colour (b) and an ombre (two mdri 7z9y) 8np0/ iakxy;uo1atone) 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 unlinkedwr5kb (63wyf t genes.

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

Sickle cell anaemia is caused by the a/2pkp3zp(l*eu e( 1ad9cqp rfllele 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,k5hi(e.e(w9el gb su between a male cat that is homozygous for brown, long hair and a f(esg(ekei 5hl. w9ub,emale cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), the allele for diamond-shaped seeds (D5k*))cyb jg*lvp 2pl m) is dominant over oval-shaped sv)kbj*c5 p*) lpgm2 yleeds (d) and the 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 porcel lctpk 2s5w/h,lus), long hair (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 heterozygousshwc t5l,/2kp 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 chage lq8mnk.utd85h93 5s: k qiprt8mpk qu9.ldnq3 ig :t5s58k he below?

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

  Which of these statemejvp-( qwtg)n/g .h ce:nts 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 showmqmd:dtz.p doc j5 xz8 ,7zz:1 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 inheritance of the disorder shown in the pedigreegetpe*2r0 jrg2*n j. o chart is X-linked rece* r0je pto*je2gr g2.nssive and not autosomal recessive?

  Different species of living organisms have (t.me a*w x9obdifferent numbers of genes characteristic to them. The tom(a*b.t 9x weable 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 qp8bm1pca+(x flower colour. If the pea plants Mendel was studying can only be white or purple and follow the rules of Mendelian genetics, which of b(m8pxapc q+1 these statements was correct?

  A biological male with hemophilia and a biological female without hemophilia1 j8: rzzh w.(h*f-20fxy4gae+ ve ss yse1nty have a daughter without hemophilia. What are the possible genotypes 1-+rxsye t (n8f s ya*jfhyz20wez4g1ve. hs:of the daughter?

  A dihybrid cross was carrievf(4(jr44kn z7pa/qs)p iejmikc h13d out between two sunflower plants (Helianthus annuus) to see if the genes for seed number and seed shape are linked. The crijkr )eac i(f4ps imjp47/(z 4n hk3qv1tical 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 can have a child with ka mmuj/h*:fd+tf)u9nlbe, *blo *9ftd,ma+e lnj)u :f/buk hm*od type O.

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

3.Explain the role of inheritance in genetic diseases.