The graph below shows the ezxed/fe1*v v q0p/g4n4c *w93 qrdzdrelationship between maternal age and the incidence of non-disjunction. Whage4qvrv/xz*0/cz 3*dfeq edwd n p419 t relationship is suggested by the data in the graph?

  Which stage of meiosis is represented in the diagram belhj/9qqg lga+, ow?

  The diagram below shows chromosomes during mei3xn8oqx we6u xn9lf i(nr.,( losis.


1.Identify the stage of meiosis from the diagram.It is    I

2.State one process, other than the one shown in the diagram that promotes variation during meiosis.

3.State when the process you named in part (i) occurs in meiosis.It is    I

  Which row correctly states the number of alleles of a single gene which wouwo d3ht.t2,siw .cf:hi897p :uz k ya(-ncnbc ld be present in tfphok n nicz8y9b3i. h. :- s, uctdw2(tw7ac:he nucleus of a cell as a result of each process?

  Which keyword is matched to the correct definitioqz5w l7(u 3ima2 z7hrtn?

  Which statement(s) a j4. navf5qft*bout mitosis is/are true?
I. Sister chromatids are pulled apart during metaphase.
II. The nuclear envelope reforms during telophase.
III. Chromosomes supercoil and become visible during prophase.

  In the micrograph below, c, t3-cevq :vfwhich letter points to a cell in anaphase?

  During which stage of mitosis does the nuclear envelope -yvxyjd/9ltoo,oe5. break down?

  Which one of the following transport proteins only carries outz*i/.qs jrk3vx*xe 2v active transport?.x *r3esq*2izvk/xjv

  Which process does not happen i/pis p8 na0b1an the shoot apex?

  Which type/s of membrane transport do/does not require energy expend*uc y6ypa(*4qbm4)df6wn ulds2 7+t zbc0tnniture?
I. Facilitated diffusion
II. Active transport
III. Osmosis

  The diagram below represents a cell wi-br6bmk mpp g12w0fm7 th a diploid number of 4. Which stage of cell division is the cell currp2rw6 bp k 1f70-mbgmmently undergoing?

  The photomicrograph below shows a root tip meristem.)t 4mdmc ei 7ik3wco)o*15,j1l lcoay Which of the following sentences correcew o37otc1llj c )a om,i *14yd5m)ikctly defines a meristem?

  When does the random olry2 .cvsvf)4rientation of homologous chromosome pairs occur?

  Which process does not occur during meiosis x.zui94xd2 hlq w4r.w?

  If a cell with a diploijainr:e9)9cw:q r0; 1c g /fykffzih/d number of 36 undergoes mitosis, how many chromosomes will be present in each daughter cell after cytokinesfe)jzi r 9 cy rk;ni:a/wf0f/1chqg:9is?

  The image shows a microgrw5c 9 twye(gc.aph of a cell.


What explains the appearance of the cell in the micrograph?

  Which statement(s) about homologous chromosomes is/are not trvwz 0c srh+wl *2sb(e/ue?
I. Homologous chromosomes have the same centromere position.
II. Homologous chromosomes have genes with the same loci.
III. Homologous chromosomes are identical to each other.

  This karyogram is for an individual wi5(*a0z cbc km/twp s;pth Down syndrome.

Which statement is not correct?

  In the cells of a horse (E. caballus) during prophase I of meiosis I there are2(9mh t.wknrk,fw,k f 64 chromosomes. What wfh r 9km2n,t.kkw,(fis the haploid number of chromosomes?

  Which arrow is pointing to o-lh)9ws t-7uc 6xxica chiasma?

  The diagram below represents the strm-b5j . (9zoo pb9fls7z6b cveucture of a shoot apical meristem. Which row in the 9(voo7-jf.zbcm p lebz6s59b table correctly identifies the processes occuring in the structures labeled in the diagram?

  How does meiosis promoo).rkav y( xu7c4f 6cb*p6zjlte variation?

  Which of the following statements is/are correct for onn;8i e b4eh1pclsj i5.t 14umeiosis?
I. It is a reduction division
II. It involves random orientation
III. It produces genetically identical cells

  The diagram shows gametes produceds+ae*rp ;afr2 *axy,u from two homologous chromosomes.


What single crossover event could have occurred to produce the gametes?
I. Crossover between Gene A and B
II. Crossover between Gene B and C
III. Crossover between Gene C and D

  Which word describes the formation of secondary tumourvk(mi ;ar4xi9s43js ws from primary tumours as a result of the movement of cell3is9;i ajr4k x(vsmw4s?

  How many chiasmata arene 6 ,r4/d fso0msohx wlm;:*l present in the diagram?

  Which statement is a similarity between cytokinesis .p2f)um3gtj uin animal and plant cells?

  Which stage of meiosis fr6 0 + wdcr qhnfo7od/j9/p.zbu7uoq4*gk .eis matched to the correct description?

  Which statement(s) are true of meiosis I but not meixkq)q7 os ;+xgosis II?
I. Crossing over occurs during prophase
II. Sister chromatids are pulled apart during anaphase
III. Chromosomes supercoil and become visible during prophase

  The micrograph shows an oocyte after the first m/ba;4 x dimotd.s3vqu qc,/n (cx:q f7(7k pryeiotic division. This results in the formation of one large cell and one small cell. What is the fate or: dt/qbs. qxnap/7fi (c 7uyvkc3(x 4do,;m qf the large cell?

  Which row correctly describes diplojj71i7d1 as.dxbk 0 fbid and haploid cells in humans?

  The following table shows th4 p9 tm.j(kn0gmu2riz e diploid chromosome number of a range of species.


Which of these statements is correct?

  What conclusion can be drawn from t*umltu- a4pp5he karyogram below?

  Which of the following processes is characteristic of the mend3o q*cgcu.7kku t35iotic and not the mitoticut*kodknu3. qc3g5c7 cell cycle?

  The diagram represents a bud with a shoot apical cah/ japi,p2i vp)bo91.+ dlf meristem.

1.State the type of cell division that occurs in the shoot apical meristem.
   is the type of cell division which occurs in the stem tip.
2.Outline what happens to the cells produced in the shoot apical meristem.

3.State two types of tissue that are produced by the differentiation of cells found at the shoot apical meristem

  The diploid number of the chimpanzee (Pan troglodytes) is dh n5 :5cl7dhsr hlg gw8w,8i248. Which row shows the correct chromosome number for different cell types and cell division stag:wgnlcsr hh gl75 wh8d25id 8,es?.

  At the end of which phase of meiosis I does crossing overgr) 0v16)r y,btvpp ug0 bvbl) occur, and what is the outco1vvlv,g))0 bupr6rtb0)yb pg me of crossing over?

  Which of the following statea;q6utps3y8tcx 66+ w75t ej hjym0xt ments does not describe a step in the sodium-potassium pump cycl; m3t+ yx0yh8a7 6e66jxwp utstqjt5ce in the neuronal cells?

  Which row in the table below is trumow ;/qszkwwh)9 eg72 e of meiosis?

Membrane transport is imporu.y z2e5 qqifex9qr (-g*r1fr t u e0.okl8t:btant for allowing particles to move across the cell membrane and responde0 xurrz lt begq8eq.fk:yi1f29qr.-(u5o* t to changes in the chemical composition of the extracellular fluid.

1.Outline the effects of placing a liver cell in a hypotonic solution.

2.Outline how the fluidity of membranes allows materials to be taken into cells or to be released from cells.

3.Compare and contrast four types of membrane transport. Include an example of each.

1.Explain how mitosis is regulallc8lj mmj6 4r8(t*udted in cells.

2.Describe the stages of interphase and their importance to the process of mitosis.

3.Discuss the importance of mitosis to living organisms using named examples.

  The diagram below shows the concentrations of diff( ttu3q; vbbf2b0mcv6erent cyclins during the cell cycle. Which cyclin is inv6 m3vtb0u(bvtcq ;2f bolved in preparing for DNA replication?

The diagram below shows chromosomes duringwpoy9op60v w + meiosis.

1.1.On the diagram above, label chiasma with the letter R.

1.2.On the diagram above, label a chromatid with the letter Q.

2.Describe the process of crossing over.

3.Explain how crossing over results in the formation of genetically unique nuclei.

  Which stage of meiosis involves the sjk4) a/buu+jf eparation of homologous chromosomes?

  The mitotic index of throat tissues taken ,wh fb)dbg*7g)nzrhhft;ht3(o3uc 7s,2 wmg from 4 different patients is shown below. Which patient is most likely to have can7zbr )sbf2h3wh ;7ggmw), on,t*cft(ugd 3hhcerous throat tissue?

1.Draw a labelled diagram to represent the prga +.5b oxdox0ocess of crossing over.

2.Compare and contrast random orientation and crossing over.

3.Outline the stages of meiosis.

  The image shows an abnormal humaav0z 8ec0nor-q 75ehfn karyotype.


What is the abnormality in this karyotype and its cause?

The graph below shows the relative amount o 9c4;7sgf2ar 1rthzjyma) 0mbf DNA in one cell during one complete cell cycle. Each letter repmy arg)10zj4c 9tb2 hr7 m;fsaresents one stage of the cell cycle.


1.1.State which stage of mitosis or interphase is represented by stage B in the graph.

1.2.Explain your answer to part (i).

1.3.Bortezomib is an anticancer medication and arrests cells in the G$_2$ phase. If a cell shown in this graph began the cell cycle at A with 3 relative units of DNA, and Bortezomib was applied to the cell culture at stage A as well, estimate the relative amount of DNA in the cell at the end of C.

2.Explain why the amount of DNA in one cell remains the same in stages C and D.


3.The diagram above shows cells in different stages of mitosis. Label one cell that is in prophase and one cell that is in anaphase.

  The diagram below shows a cr4ay (-xcry7 4 7dl.wamja azhvj5 3r;zoss between a male cat that is homozygous for brown, long hair and a female catxjdy ayar5vj4z. (z 437m ;hwc ala7-r that has black, short hair.


Which of the offspring has a recombinant genotype?

1.Outline how polygenic traits can show a normal distributiont l)vp4rn8*e7;n gpce .

2.Outline the differences and similarities between homologous chromosomes.

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

  Which gamete can result from the i ifg/;0ttcj6uav;* scrossing over of non-sister chromatids shown in the diagaiju*t; t0civ/6s f g;ram below?

  The photomicrograph shows a pollen grain from L. candidum , e glyb 5+ dgm:wmfie,0tl2b *k3*ezs(Lily). Which stage of meiosis is+te3 b*,gs5y0g*fiekl2zwdlb me:m, shown?

1.Outline the events which would lead to an individual being bk(w2w f3*s au ux l3iabo8b-mzn9//t porn with Down syndrome, which is characterised by the presen/ m-8fb3lks923t uw/ap(wn zaioux *bce of three copies of chromosome 21.

2.Explain how meiosis increases variation.

3.Outline the stages of meiosis.

The mitotic index is an indirect wb*4 ur in1:, ,*rx xrtsnh0soaay of measuring plant growth. A study was conducted ona rt,urn*0 b:x 4sh,ronsx1i* white onions (Allium cepa), under controlled conditions in a lab, to investigate the effect of soil pH on the mitotic index of the roots.


1.Describe the trends shown in the graph.

2.Outline how the mitotic index is calculated.

3.Discuss whether the data support the hypothesis that onion plants should be grown in soil with a pH of 5.5.

4.Suggest how a pH of 9 affects the process of mitosis.

5.1.Explain why measuring the mitotic index in the root is an indirect way of measuring the overall growth rate of the onion plant.

5.2.Suggest another method, apart from measuring mitotic index, that could be used to measure plant growth.

6.State one of the variables that must be controlled to make this experiment valid.

Mitosis and meiosis are two ways in whi :ni fi;,zmon/ch cells can divide. The diagrams below show two cells from an organism with a di:/ f;izmn, oniploid number (2n) of 8.


1.Deduce if Cell A is a gamete or a somatic cell. Justify your answer.

2.Identify the stage of meiosis represented in Cell B. Justify your answer.

3.1.Draw a diagram which represents Cell A during metaphase I.

3.2.Draw a diagram which represents Cell A during prophase II.

4.Compare and contrast meiosis and mitosis.

1.Outline the role of gene expression in stemiz9*6sw2jb wm growth.

2.Outline how growth is controlled in the shoot apex of plants.

3.Explain the process and applications of micropropagation.

  The diagrams below show a cell, with a diploid number of 8, in difffxrnz-m;) i 7aerent stages of meiosis. Which row correctly namnz;f i7rx a-)mes each stage?

  The micrographs show four phases of meiosis I in a plusp9xzo*r z z a+r6ob b0,h1x1ant. In what order do these p6uabxbr90z*p+zh o1s z , orx1hases occur?

Mitochondria are responsible for supplying metabolic ener9h r01uwl/sa-kv(jt bgy in eukaryotic cells. In most eukaryotes, which reproduce by sexual reproduction, mitochondrial DNA (mtDNA) is inherited from only one of 9tabwk/urjs01( -v l hthe parents: the mother in the case of humans. This is in contrast to nuclear DNA which is inherited from both parents. It has been suggested that, in some eukaryotic organisms, inheritance patterns of mtDNA found in hybrid cells, which are the result of sexual reproduction between two different yeast species, could be influenced by the parent’s genetic background.

In an experiment, scientists investigated if environmental factors could influence the inheritance of mtDNA in hybrid cells resulting from the sexual reproduction between two closely related species S. cerevisiae and S. paradoxus.

The first step in the experiment was to produce hybrid cells, which were then grown on different agar plates, each providing different growing conditions, which simulated different environmental stresses. Cultures were then taken from each agar plate and grown in a liquid medium, with the same respective environmental conditions. The procedure is outlined in the diagram below.


The mtDNA genotypes of the resulting hybrid cells were then identified and compared to that of the original parents.


1.Describe how the pattern of inheritance of mtDNA in the hybrid cells is affected by the different conditions.

2.Identify the liquid medium which resulted in the greatest AND smallest difference in number between hybrid cells with mtDNA from S.cerevisiae W303 and S paradoxus YDG197.

3.Calculate, for the 2% glucose condition, the percentage of hybrid cells which contained mtDNA genotypes of both S. cerevisiae and S. paradoxus.

4.Compare and contrast the results from the first and second experiments for the 2% glucose condition.

5.Identify the liquid medium condition which resulted in the greatest difference in the number of hybrid cells with mtDNA genotype from both parents between experiments 1 and 2.

In a final experiment, the team of scientists wanted to examine the activity of mitochondria, as indicated by respiratory competency, in the hybrid cells grown under each of the aforementioned growing conditions.
Respiratory competence was measured by using a stain, which stains respiratory competent cells red. The absorbance of cells was then measured, with higher absorbances indicating higher levels of respiratory competency.
Note that hybrid cells which contained both parents' mtDNA were excluded from this experiment.


6.State the growing condition and strain which resulted in the highest levels of mitochondrial activity.

7.Discuss the hypothesis that hybrid cells inherit the mtDNA from parents who are best adapted to their environment.

8.Evaluate the use of S. cerevisiae and related strains in the study of mtDNA inheritance in humans.

  The table shows the number of cells in different stages of the cell cycle in fowa /wekc6g;1 hw igpqs)3:4gqur samples of lung t s ;qw1egg 3iwcw/ qak)4:gh6pissue from four patients. Which tissue has the lowest mitotic index?

  The diagram shows th; .j1i/h4i/jc70u pn4v k*qxrujfg uie dominant cyclin/CDK complexes at different time points in the cell cycle. Which cyclin/CDK complex activates DNA replication machin0. *ch j iqju/niuxvg4u4k;pj7 fr/i1 ery?

  Studies have shown that gen-uj *,vyzbn0n w c(nta5 l6f1mes such as Cyclin Dependent Kinase 3 (CDKN3) are highly overw u nfny,05at*(n-zv6lc j m1bexpressed in cervical tumours.


1.Calculate the percentage increase of CDKN3 gene expression in cancerous cervical tissue compared to healthy cervical tissue. Make sure you show your working.The number is   %.

Overexpression of CDKN3 in cervical tumours has been associated with decreased survival rates in cervical cancer patients and has been shown to trigger cells to exit mitosis and begin cytokinesis.


2.A hypothesis has been proposed that overexpression of CDKN3 in cervical tumours results in an increased chance of patient death. Evaluate the evidence for this using the data given.

3.Overexpression of CDKN3 results in increased levels of cell division. Describe how CDKs and cyclins are involved in the cell cycle.

4.CDKN3 has been identified as an oncogene. State the definition of an oncogene.

c-REL is another gene that has been linked to cervical cancer and its expression is correlated with the expression of CDKN3. Using CRISPR technology, cervical cancer cells have been created that do not express c-REL (c-REL -/-). Expression levels of c-REL were checked using protein analysis.


When c-REL is overexpressed in cervical epithelial cells it results in greater proliferation of cells and the cells spend less time in prometaphase (the phase between prophase and metaphase) compared to healthy cervical cells.


5.1.Looking at the photomicrograph above, identify the stage of mitosis that most of the cells are in.

5.2.Based on the evidence provided, suggest, with a reason, which of the labelled cells would be present in the highest numbers in c-REL -/- cervical cancer cells.

cREL-/- cervical cancer cells and cervical cancer cells with high expression levels of c-REL were treated with the chemotherapeutic drug, cisplatin. Both types of cells were exposed to different concentrations of cisplatin over a 21-hour period, and the effects on cell number were analysed.


6.Using the graph above, compare the response of cervical cancer cells that express c-REL and the cells that do not express c-REL (c-REL -/-) in response to exposure to different concentrations of cisplatin.

7.Suggest a reason for the different effects that cisplatin has on cervical cancer cells expressing c-REL and those that do not express c-REL (c-REL -/- ).

8.Suggest why some c-REL -/- cervical cancer cells have a similar level of cell death to those cervical cancer cells expressing c-REL.

9.Deduce whether cervical cancer cells expressing high levels of c-REL and CDKN3 will have a higher mitotic index than those with lower levels of c-REL and CDKN3..
Cervical cancer cells with a high expression of both genes will have a  ----待选择----higherlower  mitotic index, as they are dividing more rapidly.

  When is the concentration of cyclin E the highest durt65)dyob2e pefwhte z)p3 )c1 ing the cell cycle ?