A man and a woman have a daughter a o h*kerqnb2)(nd a son. Their daughter has normal vision, but their son is colourblind. Which one of these genotypes could be correck) ( hqne2*rbot for the biological mother?

  Which diagram shows the sex chromosomes of a s-jy4iuqw8ozmxz y0d /w*: l a9omatic cell in a human male?

  There are two alleles for flower colour in snapdrp i:7qwpz8-q;6 ftmxu) ain e+agons. However, the result of a cross between tw:i zpxwpi-+q7a8) ;tq uf6nme o 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 ca 3 oz(*vz/ohnorrect definition?

  Which of these statements is a correct definition for a geo fw/yv91 n:ejne?

  The diagram shows a pair of homologous chromosrxiz/q l; v6e.q9uql5 omes.

How many loci are shown?

  Two individuals, heterozygous for a specific trait, vr13w/mj2 z;agpav6r were crossed in an experiment. Which row vz rm1rpv/aa g623 ;jwshows the expected phenotypic ratios of the offspring resulting from this cross?

  In some animals, the agouti allele causes individuala 7h-+ncp8d tt hairs to have a banded pattern. The non-agouti all dpa+n7-t 8chtele causes hairs to be a single colour. 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 seed shape in individkrokr x)z( g0;ual pea plants was either round or wrinkled. The results of an experimental cross yielded 315 offspring with round seeds and 105 offspri0)org ;xzk(k rng 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 8c/ei6 lt jrg3vaw9m3k8mni5 +v g*ty3 chromosomes. How many chromosogtacg/y63n9w vimk 38tv r jm+5*3leimes are in a fertilised oocyte of a fruit fly?

  When does the random orientation of homologous chc 9n+hu gxwmlb585l(aromosome pairs occur?

The majority of the genes in the human genome have already been mapped, cntwm+ .n o6ta3b0 b*vmeaning the exao6cb3v*wnbm +.tn t0act 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 definition of linkedry ip +gpmf01e,uw546kt+hr s genes?

  The diagram shows a karyogram of a brown male rat (Rattus norvegicus). Which 2r a 3rp0o4pbp4ba t3 ie6z)md qyim2g2h11gnarrow is pointing to a21362 i rz1 43 oqmi tag0e4pabb)rpnd2hgypm pair of autosomes?

  Mendel observed that there are two possible variations of flower colournw 4t+69qhv2*+(97 afemsixehc gsuf in pea plants, purple and white. After a genetic cross, the ratio of pcnuwhve7ts+f96qs29+ a( fx hg *e4mi lants 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 ink d)fjozqs 782 London in 1991. kz)f28qjo s 7d

  Which of these traits is an example of continuous*dw l cc:z- qe0:e0grl variation?

  Which row correctly describes diploid wxq3 yz3zgw e;l5 *jl(and haploid cells in humans?

  The following table shows the diploid chromo y7)r.)yryokm some number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a rece1ut *m* pglgmns,hj3wxy . uj8;c3g:lssive 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 blood type O. What are thwy;5l-7 x t9txjd )cjjyov :e* ;g.ekbe possible genotypes of the biological father? e jxy d:tckv)yl* e-jt;gb;o.jx7w5 9

  Which row shows the wiku.44peao qu:m) gaaxh 92z:6i8z/7tw o ascorrect annotation of the alleles for blood groups?

  Which of these statements ari,jj 74bj elih1fnt76 f- jc)se 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 anaemcz 28lz hk/08 nkbym,eia and the spread of malaria across the continent of Afric c8 02 8ylnzkkzbem/h,a.


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 (Equusd,:ue tgxs (ophq8k5 8 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 (P) is dominanteg85qhu k ,8txos d:(p 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 uj(2ezs0c;a -c7t*w tx7 fqrcwnlinked genes.

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

Sickle cell anaemia is caused by theyx)4j:x5lg g i 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 tiv6711sl)q geq : oxkhhat is homozygous for brown, long hair and ahs:1qg6 7e1oiklv) xq female cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum 1gea*myor5 +o officinale), the allele for diamond-shaped seeds (D) is dominant over oval-shaped seemgyaor+e* o5 1ds (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/p*obd od3ri6xq m(h 7 porcellus), long hair (L) is dominant to short hair (l), and curly hair (C) is dominant to straighd(/m x qi7*3rbho6pdot 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 yq/uir.hf oqm, 4*(a6itt+qh pedigree chart be,+hf/tqiu( 6io*mq t.y qhar4low?

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

  Which of these statements about genetic disorders is9fh o .psb(np9/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 norma4oxv np7)c:uo1h+6 d w-nrc sol distribution.

2.Outline the differences and similarities between homologous chromosomes.

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

  What suggests that the m 0+p q4,yzdx/q gnht8(fzz 3vb xha)1inheritance of the disorder shown in the pedigree chart is X-xn hb1h pxv )qq+zazym 8g(3/d4t,fz0linked recessive and not autosomal recessive?

  Different species of living organie6sv.-bdxzo p-mzo ,88ru +s jsms have different numbers of genes characteristic to them. The table shows the estimated number of genes -. j8v+dbmrp68ss xz -zo,o uefor 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, inclcf( 1 pc :ccjxo-n2mj6uding 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 corx (c1pc 6jc2cn o-jf:mrect?

  A biological male with hemophilia and a biological female without hemophilia h1m7:mgri bz3 ckh*bx.ave a daughter with mx *:z7rgh .m3ikb1bcout hemophilia. What are the possible genotypes of the daughter?

  A dihybrid cross was carried out (qwbh0kpah ;:zr4 +s rbetween 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 significance level was 7.82. The calculated value for the chi-squared test was 10.05;hbws 0aq; zk (rr4:ph+ what does this indicate?

1.Explain how parents with blood type A and blood type B can have a childy3z 2jbrq-o3h with blood type O. 3 o-r3bz h2qyj

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

3.Explain the role of inheritance in genetic diseases.