A man and a woman have a daughter and a son. Their daughter c7*tdq3yv:*uq/ec 4 zmovq)s has normal vision, but their son is colourblind. Which one of these genotypes could be correct for the bioloe 4ctq **ouc zqqymv)7v3 /s:dgical mother?

  Which diagram shows the sex chromosomes ofn*+u/6qs kjwgy(fjc vj d7*4la.u rn5 a somatic cell in a human male?

  There are two alleles for flower colour in snapdragons. Howee p793j4otapyd 9tueb v941 :t)wqokd ver, the result of a cross between two heterozygous plants yielded offspring with three different observed q t 3ueboeo49p7k:9twpayt d 4jd)v19phenotypes, red, white and pink flowers. Which is the most likely explanation for this observation?

  Which keyword is matched t2ci mi6brj yn/bl7+ 3to the correct definition?

  Which of these stateme:i6 fyfs*vi .:fqk.niod)(jhnts is a correct definition for a gene?

  The diagram shows a pair of homologous chromosom ac3t0-/bgdj dt) 7rfses.

How many loci are shown?

  Two individuals, heterozygowg1m t m7q37nskb5vo1 us for a specific trait, were crossed in an experiment. Which row vwtm3 g7s qkm7ob1n15 shows the expected phenotypic ratios of the offspring resulting from this cross?

  In some animals, the agouti allele causes individual hai1*va9k* ztx c:gq2vy (vsqg 8trs to have a banded pattern. The non-agouti allele causes hairs to be a single colour. Individuals who are heterozygous hav1gg(tsv*v2kc xy :atq q98v*ze 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 pea 6dy uqb/,/cokxf2f;r plants was either round or wrinkled. The results of an experimental cross yielded 315 offspriqky6ufoc/d f 2 b;r,x/ng 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 (Drosophb: yo,e:+oilqila melanogaster) have 8 chromosomes. How many chromosomes are inei ,q:+b ooly: a fertilised oocyte of a fruit fly?

  When does the random orientation of homologoushn g-:xrwhid+ e*wnt gr33z/1yqy ( f3 chromosome pairs occur?

The majority of the genes in the human genome 8wpf:jtee6j6gwmzil0,8uh( g11jlx have already been mapped, meaning the exact locations of the genes on chromosomes are known. The diagramt(g izxfl16p je: ,j8ujwhge60lw8m1 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 oc cy6f6dl)-ip+ ygz leh -k ;jg1s)4fkf linked genes?

  The diagram shows a karyoz i//zu(gz-/x q-ws pogram of a brown male rat (Rattus norvegicus). Which arrow is pointing to a pair of autoso sguq-zxp /w(z/o- zi/mes?

  Mendel observed that there are two possible variations ogkuxte 2t ; 9cv*-r2vxf flower colour in pea plants, purple and white. After a genetic cross, the ratio xu2cv gtxe9v;-tk2* r 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 weight of children bopg/k7: 1edrn3ojn (cjrn in London in 1991. pg/13ncn7 ( rjj:edko

  Which of these traits is an example of continuom paaw,(i;hi+ us variation?

  Which row correctly describe/6 v yuvtr2us te)08hos diploid and haploid cells in humans?

  The following table shows the diploid chromosome number of3 3(y sl/yyz3f gd4ol2j e6ean a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recessive alio/7tbq j)h3e-d7 dyulele (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 tygih tqawkc73m,kiw mih )x. 3,lt+ (9kpe O. What are the possible genotypes of the biological fathermitck(i+w7)ig3m,kxt9 w ahhl,qk3. ?

  Which row shows the correct annotation of the alleles for blonh9ye; h n8/wsod groups?

  Which of these statements are true2+plio.ijdrnc 647p j 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 anaemia and the spread tog7f az -+s.qof malaria across thef-za. gso7 +qt continent 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 przewals iq aa;a ygdj94.h6uci p m3v.ys1qu. tc(:q2ikii), 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 dominanap ay2q.ici. cmg1qhd.;ua6 i:u(y9 j s4 t3vqt 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 betweenxc8wa24:mm t w linked and unlinked genes.

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

Sickle cell anaemia is cause4ne-4 :v lu7qr8py dqfd 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 cat3qigc2i 2fct7 that is homozygous for brown, long hair and a female cat that has black, short hair. 2i7c i3q gcf2t


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officinale), the allele for diamond-shaped h0k 3 8r gtqx63zmny-gseeds (D) is dominant over oval-sg- r3hmz6q3yx08knt ghaped seeds (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 porcellus), lft l ux+ ao0ju)9vz0:oh+l xmn5 n2vo)ong hair (L) is dominant to short hair (l), and curly hair (C) is dominant to straight hair (c). A test cross was carried out belnj:n f2o0hl0)ax9u+m tou)5+vo z xvtween 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 inheritkyq.eq 4bl (s 8e+jfu;ance of the condition shown in the pedigree chart beloe.;y jse4q8ukf+lb (qw?

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

  Which of these statements abobtt7 4 )pftz8rut 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 show a s4mf2elt3k a 0no: 73r6 9swwus exop)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 dibe1/(h btze7 csorder shown in the pedigree chart is X-linked recessive andhb 1t/7 (cezbe not autosomal recessive?

  Different species of living organisms have different numbers o;jves* 7hs t8uw ix4:i12op.ua)mdlb f genes characteristic to them. The table shows the estimated number of genes for five specietws xb*4i7 d;la:s v)pu.eihu mj21 o8s.
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 c953s+vv*x ea+tuivk sharacteristics of pea plants, including flower colour. If the pea plants Mendel was studying can only be white or purple and follow the ruls vvsa 5+*xu3e+tkiv9es of Mendelian genetics, which of these statements was correct?

  A biological male with hemophilia and a biological female withonzbg9au yb./6bbr e4 4ut hemophilia have a daughter without hemophilia. What are thr/buba6b ebz4.n49gye possible genotypes of the daughter?

  A dihybrid cross was carried out between two sunflower plants (Helianthus8 ,dn/z1a 7 oud)zctcy annuus) to see if the genes for seed number and seed shape are linked. The critical value for the ud, cz ato7cdyn/)18z 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 bloo 5c0bbuxz,zv n7r u0dto7 m2t3d type A and blood type B can have a child with blood type O.z0,t7bm bxur 37 2zvnu t0co5d

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

3.Explain the role of inheritance in genetic diseases.