A man and a woman have a daughter and a son. Their daughter h4mm)g 8ayn*lg7a-v tirp (y 8ias normal vision, but their son is colourblind. Which one of these genotypes could be correct for the biological momg7-i88 yrg 4li*na v)yatm(pther?

  Which diagram shows the sex chromosomes of a somatic cbi :6: bicn my,cu:rn;ell in a human male?

  There are two alleles for fzpeb1l7yg* otlf 94 ppv: 83gzlower colour in snapdragons. However, the result of a cross between two heterozygous plants yielded offspring with three different observed phenotypes, red, white and pink flowers. Which is the most likely explap1 p7o yftbv3:*4 9 zgplgz8lenation for this observation?

  Which keyword is matched to theyi ynn 0(0:mfj correct definition?

  Which of these statements is a correct definition f9q:l9yjstyx.au vov gt g2 6d9 +6+najor a gene?

  The diagram shows a pair of homologous chromosomes. u1zy -iw+7p ; fts-rwc

How many loci are shown?

  Two individuals, heterozygous for a . wmz( b r6om,on7+- bp8azjzpgki 6w7specific trait, were crossed in an experiment. Which row shows the expected phenotypic ratios of 8oww7 +-,bnozz66gbk7zi .parmpm ( jthe offspring resulting from this cross?

  In some animals, the agouti allevkw3 7ytmmc.: ( qsi77kgjr31ie-tg rle causes individual hairs to have a banded pattern. The non-agouti allele causes hairs to be a singlt377i(-kmrgs ekmcqw3t vj 7ry i1g:.e 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 individual pe)culw.(i bj e8a plants was either round or wrinkled. The results of an experimental cross yielded 315 offspring with round seeds andi(e .ujwl)b 8c 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 me)8 msedhaq/ ,nlanogaster) have 8 chromosomes. How many cd,a8/sm n qeh)hromosomes are in a fertilised oocyte of a fruit fly?

  When does the random orientatiw:x7 fnhx:4;my qfrk(on of homologous chromosome pairs occur?

The majority of the genes in the human ge xo,pquu*b+wmqqe ;*/nome have already been mapped, meaning mu+qep ;x *b/wuq*q, othe 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 definition of lin9nt ylu)l xc6o 5. 1w 5vgqpo;qs 23vjlnmxz*7ked genes?

  The diagram shows a karyogram of a brown male rat (Rattus norvegicus).fnjz.:c:h / c3lq y)lu Which arrow is poin.h :lqy)3cljn :c zf/uting to a pair of autosomes?

  Mendel observed that there are two possible variations of flower colour in peoe ,hwewca x 0e2o,*1sa plants, purple and white. After a genetic cross, the ratio of pwa0,,1h2s cewoe e*o xlants with purple flowers to white flowers is 1:1. What were the genotypes of the parents?

  The graph shows the frequency of birth weighti phboex+no/ 1614 q0ikz .qdt of children born in London in 19916hqq.i4t /+bk x10p1doz nieo.

  Which of these traits is an example of continuous variati7804w 6ms)bf hx wnqcxon?

  Which row correctly describes diploid and haploid cn8d 9e:w*x divells in humans?

  The following table shows the diploid chromork3fk(1d+jg;m +m9*bktf) gw s1r intsome number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recess i87k74nqfiyvive 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 ch ,*c gnxu g*qqmb fu02n26x8scild with blood type O. What are the possible guqgx,s n0nc 8xq*c 26bu *2fmgenotypes of the biological father?

  Which row shows the correct annotation of the alleles for blood grnipk 7 q 6dl))z,ay muud/0k5foups?

  Which of these statements are gj5upv 6d: axw5eqrzs c7o:38true 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 incide h8sg(/nu jsby, g0fb5nce of sickle cell anaemia and the spread of malaria across the contin8b0ufn5b sysg h( ,g/jent 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), fur colour is determined b9ay;:7i u:a,evpht z gy a number of genes. Brown coloz:y te7ph9 u;aa,:giv ur (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 and 9gu7kwh ((h aa*8cms sunlinked genes.

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

Sickle cell anaemia 5vt n z/ ava8/xre6b(jis 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 between aginq)4n ,jmtoss3;ef 4 ,t q6f male cat that is homozygous for brown, long hair and a female cat that has black, short hair.4tg4einq) ;fjf6ns ,3q, sm to


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), thbucq 1wv9 y/:csgoly l*..bb6eb8z5 fe allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the allele for long :q.b/ w bls8y5.bl ocgfe96z vu1byc*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 domiypy.du-(( vip nant to short hair (l), and curly hair (C) is dominant to strai yip ((.v-ydpught 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 pedigrvw*fj7ar b31 p8unt)gee chart bel)v 8p7jagurb n1*fw3t ow?

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

  Which of these statements about genetic disoh) jqryj.z2 ,2m(*lwqsc ck w.rders 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 show a normal distr7agflz a :9ccxd4 .tz4ibution.

2.Outline the differences and similarities between homologous chromosomes.

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

  What suggests that the inheritanm++g(k q z+8.3wmettm kufv 4zce of the disorder shown in the pedigree chart is X-linked recessive and not autosomal r .umke +vz4(f3m+mqkz tw gt+8ecessive?

  Different species of living organisms have different numberi tu8) llf)g.hs of genes characteristic to them.)gl 8fltuh)i. The table 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 characteristicsa+66g qk+saubjr cufc8r6 /. l of pea plants, including flower colour. If the pea plan8ck6 6guj.rc ba +/l6ur+fsqats Mendel was studying can only be white or purple and follow the rules of Mendelian genetics, which of these statements was correct?

  A biological male with 03 hcdxgq2) z.kf1 2tdeyss,mhemophilia and a biological female without hemophilia have a daughter without hemophilia. What are the possible genotypes of the d,x 23k0ehsfg qs)dy c1.2m ztdaughter?

  A dihybrid cross was carwnq/6(kqbo h o2r7 g.jried out between two sunflower plants (Helianthus annuus) to see if the ge w2o(h7q6qgoknrjb. /nes 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 indicate?

1.Explain how parents with blood type A and blood tyt6 ys9fyqqm/, w4lih2pe B can have a child with blood tylyf/siymt,hq9246w qpe O.

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

3.Explain the role of inheritance in genetic diseases.