A man and a woman have a daughter and a son. Their daughter kh ow2q,ao . 35 v,y .dt0t8pai*kdxochas normal vision, but their son is colourblind. Which one of ht.8ok3oo., 5adykpv2cqw ,itx *d0a these genotypes could be correct for the biological mother?

  Which diagram shows the sex chromosomes of a somatic cellle7auhb85d+qz 7 ty d) in a human male?

  There are two alleles for flower colour in snapdragons. However, the result:yq7k em h/u,a of a cross between two heterozygous plants yiel7hqmk,/ u a:eyded 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 therof;f 5j/g 4 :ppxe,2 d.m0d au8yosqm correct definition?

  Which of these statements is a correct definitol v- 1lbq:7giion for a gene?

  The diagram shows a pair of homologousradvarj 61,s. chromosomes.

How many loci are shown?

  Two individuals, hetek-/n..ewj 2uii al+ yqrozygous for a specific trait, were crossed in an experiment. Which row shows the expected phenotypic ra. iwu+lj kq.-/an2eyitios of the offspring resulting from this cross?

  In some animals, the agouti allele causes individual hairs to have a banded patt tc(/*)83i tullx9ax/ pvrqhfern. The non-agouti allele causes hairs to be a single colour. Individualstfpt8*9ri( l)h vax /xqcu 3l/ 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 y1 y i2j06tjg lw1fo4rpea plants was either round or wrinkled. The results of an experimentar1yftyjgj 1o46w 02l il 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 (6yp-g (vfg2axx 9sp.uDrosophila melanogaster) have 8 chromosomes. How many chromosomes are in a fertiliseyggaxv 92s p .xpfu(-6d oocyte of a fruit fly?

  When does the random orku4q/ l /ilk9 pvgf3juf0/6vcientation of homologous chromosome pairs occur?

The majority of the genes in the human genome have already been .sbq ysznx2r/- y2 rq+mapped, meaning the exact locations of the genes on chromosomes are known. The diagram below show/q-y2rs.xyq2+z n sb rs 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 def jyx:84 .st u2nnvok(sinition of linked genes?

  The diagram shows a karyogram of a brown male rat (Rattus norvegicus). Which arrcn0xu 7+kipa-ow7ax u-cik0+pn is pointing to a pair of autosomes?

  Mendel observed that th58zzauk d2 a(wib6q h4ere are two possible variations of flower colour in pea plants, purple and white. After a genetic cross, the ratio of plants with purple 8d z2ah6 kzqbiwa5 (u4flowers to white flowers is 1:1. What were the genotypes of the parents?

  The graph shows the frequency of birth weight of children born g myd44e mhb+4492:qbblm/tpw d qkv. in London in 1991. mhp4v kqd+eb yt2m/bb4 gld4mq4: 9. w

  Which of these traits is an example of continuous variatifhylb0 0ufn v04:j.04mai qb0 rn cph/on?

  Which row correctly describes diploid p,)pknrwd +5i and haploid cells in humans?

  The following table sh( vet;ac 17tli* mu8qrows the diploid chromosome number of a range of species.

Which of these statements is correct?

  Sickle cell anaemia is caused by a recessive alvs mu2z1)x a/b p2u8belele (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 o:/iae 2 ;tycexqsroi m tg3i(-c(( b5type O. What are the possible genotypes of the biological fi bci :g23 t(-ra( oc(iemy;e5qos/ xtather?

  Which row shows the correct annotation om-6 sr + fk qbw(d+;tc.v3oloof the alleles for blood groups?

  Which of these statements are true for alll g2r(jmju1*,xqyf2*2gac5 sz1 2cl p6 bbpcyeles?
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 maa 68dlun)y;( au-ufpw laria across the continen )au 6;uaflwuny- 8dp(t 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 bc pz1eyj5duz05l6 x,2eb-muoy a number of genes. Brown colour (B) is dominant to sandy colour (b) and an ombre (two tone) colour (P) is dominuu jd c2ozez10y 5bm5epxl,- 6ant 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 lj/b*vo d) dbz+inked and unlinked genes.

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

Sickle cell anaemia isv 8+dztse-9ib*qxm 6u 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 a male ca fh9aq1ufg cz8ei+8n 0t that is homozygous for brown, long hair and a female cat that has black, short haihfqf8n091+gu iza8 cer.


Which of the offspring has a recombinant genotype?

  In dandelions (Taraxas0 no)1eczjk ,g(xc4jcum officinale), the allele for diamond-shaped seeds (D) is dominant over oval-shaped seeds (d) and the alxn(,e s 0 )zj1kojc4cglele 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), lonhoc*n,yu jb9:tj-s:b g 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 heterozygous long, curly-haired guinea pigs and female short, straight-haired guinea pigs and a chi-squared test (χ2) was carried out oujy c:,st : njobh9b*-n 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 inheritanceas5hu+q w shr79pj.l e*3*syx of the condition shown in the pedigree chart bqahheslrs3* 7 9.+*j5wy upsxelow?

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

  Which of these statements about genetic disorders is/ .2fxxe(m kw)ware 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 polygenikk+u mr w4sb 2)0jq* tqtcenk) j:9qe3c traits 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 disorz:+7*pqaxvar khnrfd 8v. f3 3der shown in the pedigree chart is X-linked re .+a3rkrqff*7h8dp xaz :3v vncessive and not autosomal recessive?

  Different species of lmb 3f79et3ny. hkn 9peiving organisms have different numbers of genes characteristic y .3 ne 3mb97n9ftpkehto them. 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 characteristics of pea ple rweypv*8u2zo11/ud-e3mk6g orn1 hu:s v7lants, including flower colour. If tslnuvew/dy 1k 3-ermo8oh7 1e 2u*ru6:1v gzp he pea plants 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 hemophilia and a biological female i i,nd5lpkd0t3ln 1 i75cp2av.dxfx-without hemophilia have a daughter without hemophilia. What ad5 ,ifn5kinp 2. -l xx3d7icta ld0pv1re the possible genotypes of the daughter?

  A dihybrid cross was carried out between two sunflower plants (Helianthus z hw3l8s gl)jsash, q0k )zk9-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 sq0,9- jkak8szs )hl ghwl3z)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 0n,m* 7kdz ilea child with blood tyn 7e, lzmdi0k*pe O.

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

3.Explain the role of inheritance in genetic diseases.