A man and a woman have a daug h2 ch*jgzyy0,hter and a son. Their daughter has normal vision, but their son is colourblind. Which one of these genotypes could be correchc 0 g*,zj2yhyt for the biological mother?

  Which diagram shows the sex chromosomes of a somatic cell inpv1jhk )6wvgisw00uu5 7. apa a human male?

  There are two alleles for flower colour in snapdragons. Houqtu0-8 d yim95kp 2ugh )3zsiwever, the result of a cross between two heterozygous plants yielded offspring with three different observed phenotypes, red, white and q08ph9u)3uys 5i gkmuz i- d2tpink flowers. Which is the most likely explanation for this observation?

  Which keyword is matched uzs7 1g9i 1ajwto the correct definition?

  Which of these statements is a correct definition for a u7cuj0 frd28.wqn 6ap gene?

  The diagram shows a pair of homologous chromosomes.o/qqa3 ea2u5 7ykecq6

How many loci are shown?

  Two individuals, heterozygohz xg0 ex5o3t .;d-wwqus for a specific trait, were crossed in an experiment. Which row shows the expected phenotypic ratios of the offsprinz gxdw.xtw5 qo h0;3-eg resulting from this cross?

  In some animals, the agouti allele causes individual hairs.s-*9zzc*p fiyr4h o xtc/u8v to have a banded pattern. The non-agouti all8 x .zf-r4zc/suiy*hct 9*o pvele 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 individual ph ek8fa*eu f)g 2u *uet7+vl2hea plants was either round or wrinkled. The results of an experimental cross yielded 315 offspring with round seeds and 105 *eu+l u2eh) v*7ue8fg 2tkafhoffspring with wrinkled seeds.

Which row in the table below states the most likely genotypes of the parents?

  Neurons of the fruit fly (Drosophila sq*2ncda 8n;umelanogaster) have 8 chromosomes. How many chromosomes are in a *c sda;nun2 8qfertilised oocyte of a fruit fly?

  When does the random orientation of homologous chb,51tw(pttw r snv5*lromosome pairs occur?

The majority of the genes in the humangbz*) + xxkf y v/-h/t2jj5abm genome have already been mapped, meaning the exact locations of the genes on chromosomes are known. The diagram below shows one representation of a homolog5gt// jbxh2m+vzak-yb x *jf) ous 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 linked geex lj57) xj. xjui-u3mla8.ny nes?

  The diagram shows a karyogram of a brown male rat (Rat/()y3de xay/gbahk3oi2hq /r 5.p q kftus norvegicus). Which arrow is pointing to a pair of apqh/b3oq53kdxa / eh/gfy r)(yk2ia.utosomes?

  Mendel observed that there are two possible variations of flower colour in pw;o3qe4e55ibpd -+f pe9caqt ea plants, purple and white. ; ee5fbcpqaetow 5 3-pqi4d+ 9After a genetic cross, 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 birth weight of children born in La.njys.k .+r1a 4xr,himeex 8-w ) ysvondon in 1991..y, xee+r4y8m)his j .n k sx.vara-1w

  Which of these traits is an example of continuous vl oc4f89 pu1uhrla (re*5n y1rariation?

  Which row correctly describes diploid and haploid cel ri/ we;c-6jd3ymjqw)8sm cs/ls in humans?

  The following table shows the diploid chromosome numkvr u12yi e+0qber of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recessive allele (Hbh .oitvn+s/ 5r$^S$). 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. r)d j1p6-j e,6vkjtpkWhat are the possible genotypes of the biologick6 e6dpk jr v-pj),j1tal father?

  Which row shows the corre0 :h ch0 pvz;8rf ula,2yp3vmuct annotation of the alleles for blood groups?

  Which of these statemen, ,u5, hgwcwqlts are 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 anaemia and thrfj8v5zb*r xc5v5g; /eg/ql ce spread of malaria acrosxe lg;8/5rcb /jz5r vcfgv5q*s the 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 przewalskii), ysfurtq 09py /p,n9 5nfur colour is determined by a number of genes. Brownt09 /u5,nn ys 9fpqpyr colour (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 linkbew; btxr 44g2-nh6txju l6 q-ed and unlinked genes.

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

Sickle cell anaemia is caused by ti0ejpvy 3i r7r+wm /x)he 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 betxww: pz+rx;r, 5t3ghmween a male cat that is homozygous for brown, long haih, wm+prr: 3z5xwxtg; r and a female cat that has black, short hair.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxacum officina xoy e8r*n- ne5lgx1a9t)y+wxle), the allele for diamond-shaped seeds (D) is dominant over ovnt8 xrlyx1w*ex n 5+)oya9ge-al-shaped 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 po0n mfg* t-dd(ft. utx0rcellus), 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 heterozygou0ut *-dngftx.fd0m(ts 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 t+ew:m6yiahpn v2/f0 h he condition shown in the pedigree chart b fhh 2nv/im6pe+ :ywa0elow?

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

  Which of these statements about genetic disord50f) p-n1z 5dmzgfdyzers 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 traitg(0pifytcef4y p a)a 0)e 29fys can show 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 showxt ye6h0w 50qibzg 2z8uk;p;pn in the pedigree chart is X-linked recessive and no0w k t6xbi zep;gqh5u; 8yp20zt autosomal recessive?

  Different species of livi16rbmfr z1(s- h ldqigj 7wfsq4x-b1,ng organisms have different numbers of genes characteristic to them. The ta ssql mdzbfq6-b 1 jrh1,irgfwx4( 17-ble 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 characteristi1o6 / cgosm0dnp/ ahr(cs of pea plants, including flower colour. If the pea plants Mendel was studying can only be white or purple and follow the rules of Mendelian geneticnp6 /masc (r0ghd/oo1 s, which of these statements was correct?

  A biological male with hemophilia andm ++joubu+dt 9 a biological female without hemophilia have a daughter without hemophilia. What are thjtmu9ub++o d+e possible genotypes of the daughter?

  A dihybrid cross was carried out betweenx 3 a6twle50gl two sunflower plants (Helianthus annuus) to see if the genes for s0lg5weax6t3l eed 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 a ;d:s1ngvkfjvda.c yg (gp: m8jvt, .5nd blood type B can have a child with blood gdt pd,8a:j mv5f..g;vvnc (ysjg 1:k type O.

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

3.Explain the role of inheritance in genetic diseases.