The graph below shows the relationship between maternal a:z)w - .0v rqhutmr+-yrmfts9ge and the incidence of non-disjunction. What relationship is suggest)-tmvw fyuh0qrtr9 r: z+-.smed by the data in the graph?

  Which stage of meiosis is repre 91oey5yz3m8izao0 u psented in the diagram below?

  The diagram below shows chromosome+t fgvq j69s h j1lp5d;4jlpg6s during meiosis.


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 numbe qv:9(imqq1 kps)nh1q r of alleles of a single gene which would be present in the nucleus of)p:v1qkh qm9q 1sni( q a cell as a result of each process?

  Which keyword is matched to the correct dquz u uo.d6v+8rh8emhv8.gf- (yp8nf efinition?

  Which statement(s) about mitosis is/are kz2: gh*e9cx 8.cxhndwu98c ptrue?
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, which letter poinz-vwtw4xto6 o n2:+soi0 psa+ts to a cell in anaphase?

  During which stage of mitosis9zfmw 1wmmcz0g70o a7 does the nuclear envelope break down?

  Which one of the foljk, 0p/ eg3 y5r+fijijlowing transport proteins only carries out active transport?+rgkiy/i j 0j35pf je,

  Which process does not happenvs/ycu 7xy1+zd j5 /lg in the shoot apex?

  Which type/s of membrane transport do/doep8rq sewi11e. fm-+x-mav2n ts not require energy expenditure?
I. Facilitated diffusion
II. Active transport
III. Osmosis

  The diagram below represents a cell with a diploid number of 4. Which sj-9yjilm8 o5wtage of cell division is the cell currently underg 8m5y9o ij-jlwoing?

  The photomicrograph below shows a roo*j u *wm.stv5o/g,lyyxd , 5xot tip meristem. Which of the following sento*,j/ l 5m d.syyt*vxx ug5wo,ences correctly defines a meristem?

  When does the random o8 elc9t7s6p igrientation of homologous chromosome pairs occur?

  Which process does not n /h7bbk9gvn1occur during meiosis?

  If a cell with a diploid number of 36 un;oec g8:qn(i /f h n7xk4fbf:mdergoes mitosis, how many chromosomes will be present in each daughter cell ; / fgnhq kiobn4(c8mef:xf7:after cytokinesis?

  The image shows a micra2f2u ku v4/s.au1h auograph of a cell.


What explains the appearance of the cell in the micrograph?

  Which statement(s) about5p1mw,:gy1ft9ayq o a homologous chromosomes is/are not true?
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 wimmy/5k9b* ;2mien*r(:d e rl)hn pozith Down syndrome.

Which statement is not correct?

  In the cells of a horse (E. caballus) during proph9 wm n7-.lz7mip9ss/m j8 ihciase I of meiosis I there are 64 chromosomes. What is the haploid number8 m/snw-i7.9si9jmmclphiz 7 of chromosomes?

  Which arrow is pointing to a chiasma? +nw eig5i1 cv)

  The diagram below represents the structure of a shoot+k b3qhbr,,yt+fa aq: apical meristem. Which row in the table ky:+ bf btq,ar,+ aqh3correctly identifies the processes occuring in the structures labeled in the diagram?

  How does meiosis promote variati;rvik) -xhgbv.f+c6wk grt l-3(b fs.on?

  Which of the following statements is/are correct for meioso +58 w 30ycyrkh-wowuis?
I. It is a reduction division
II. It involves random orientation
III. It produces genetically identical cells

  The diagram shows gametes produced from two homn xm+9rqp +w(uologous 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 tumours from primary tumours as oe+6kw j; lm(rz-v7wq a result ov+7rljw em 6 qok-zw;(f the movement of cells?

  How many chiasmata are c hsxhb e39b4-present in the diagram?

  Which statement is a similarity between cytokinesis in 52pkb y/dkh, nanimal and plant cells?

  Which stage of meiosis is matched to the correct descriptiondq w+5bf)fv*m ?

  Which statement(s) are true of meiosis I but not meiz42iyjb kk5sqs;,k au8r.5 y losis 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 aft2q0auf(2ip7iutoul 1 er the first meiotic division. This results in the formaou7i (q2f0ulut pi21ation of one large cell and one small cell. What is the fate of the large cell?

  Which row correctly describes diploid a0 fpo-mfd;h4 jnd haploid cells in humans?

  The following table shxa)ks /1 b)ypmows the diploid chromosome number of a range of species.


Which of these statements is correct?

  What conclusion can be drawn from the karyogr,dn0a vqm yve:25uwc3 am below?

  Which of the following processes is characterf7gf h4:kv)rw/ jvja.acq xk-- j3ed )istic of the meiotic and not the mitor3-7ah 4jkw) qg:v ak. fevf-d)j/cjxtic cell cycle?

  The diagram represenv,(.d iop i/jtt61 (rv+(grxrnzn ( cqts a bud with a shoot apical 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 48. Which row shju .l .1)lo9kl 3xqpzvows the correct chromosome number for different cell types and cell division stagel.z3.9 vquolj) l k1xps?.

  At the end of which phase of meiosis I does crossing over 1jxdk(+)i f 60i r;1rlsbqsy foccur, and what is the outcome of cros x)biqk( 1j+;dyf 0lrs1isfr6sing over?

  Which of the following lfe-b f) s qv0*c.f6aastatements does not describe a step in the sodium-potassium pump cycle inb 0elf-*fcq6vf as .a) the neuronal cells?

  Which row in the tabbxx7z.s 4-s;r+vn uqgle below is true of meiosis?

Membrane transport is important for allowing particles to move acr,1 xlkyk 9wibj88w(wvoss the cell membrane and respond to changes in the chemical composition ok89( ,i1yj ww8lvwbxkf 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 regulated *1t;;sa5qe9wu ghl8l. pxr)fiv ihu2in 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 different cyclins durir .sfnh0of0,7 eh,q dbng the cell cycle. Which cyclin is involved in preparing for DNA replicahfh0,7 qrd o,enfsb.0tion?

The diagram below shows chromosomes during meio :f*duvp2+mqw10frx / nxh4hisis.

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 involveu-lob ,h/2xm xqk(d5e+d 0nzos the separation of homologous chromosomes?

  The mitotic index of throat tissues taken from h2krxhe uxgx 5zz01 -k (ztj6vw6.;wl rc7fk54 different patients is shown below. Which patient is most z6zw ( .1v;hgwk0eh6rrc57txx5 -kxz2f kjlulikely to have cancerous throat tissue?

1.Draw a labelled diagram to represent the process of cro tlp2 q8u2bp1wssing over.

2.Compare and contrast random orientation and crossing over.

3.Outline the stages of meiosis.

  The image shows an abnormal human kah9u co m6x0yk 0;uu*ctryotype.


What is the abnormality in this karyotype and its cause?

The graph below shows the relative amount of DNA in one cell during o+tygjo. np5-wne complete cell cycle. Each letter-p +gjw. 5otyn represents 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 cross between 12h u c d7+1dfl4vvitba male cat that is homozygous for brown, long hair and ldu1vvdc 2 t71b4fi+ha female cat that has black, short hair.


Which of the offspring has a recombinant genotype?

1.Outline how polygenic traits can show a normal distributio v0h3f apbg.6x/f7cqp-2h vgd n.

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 crossing over of non-sister chromatids shf4ovbj*k 7z7s own in the diagram below?*v7bojsf7k z 4

  The photomicrograph shows a pollen grain from L. candidum (Lily). Which stage oyrr6cq le .14enw nio5g4k33 mf meiosis glem r5ke ociw4 36.q34y1nrn is shown?

1.Outline the events which would lead to an individual being born with Down sh5 k 9t+n+tm kqm.)sahyndrome, which is ckm9+a5)qkh.hmt n+stharacterised by the presence of three copies of chromosome 21.

2.Explain how meiosis increases variation.

3.Outline the stages of meiosis.

The mitotic index is an indirect way of measuring plantuh5bnsu4 rr. 2*bl6w8 pbes 9l growth. A study was conducted on white onions (Allium cepa), under controlled conditions in a lab, to investigate the effect of soil 8w9l 5h6bp4lsnue.s *rb br2upH 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 which cells canc,ug)6 ;,ub ev v:sysfafq4:r divide. The diagrams below show f, :6);reuga c vqf: bsuv,y4stwo cells from an organism with a diploid 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 dvzyom /07fq 4in stem 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 numbe-fmh c7 a2* q;3 mjhqidg;k6qrr of 8, in different stages of meiosis. jk-2f73*q;;qgri6qhdmc ma hWhich row correctly names each stage?

  The micrographs show four phases of meiosisjw9h4- sihyai a:gh*vwoy (:; I in a plant. In what order do these phases oi:a-ihy(w:9 hh*j wy4s g;ovaccur?

Mitochondria are responsible for supo:;krez w.8 nu 0abdy4ae q)79efsq y6plying metabolic energy in eukaryotic cells. In most eukaryotes, which reproduce by sexual reproduction, mitochondrial DNA (mtDNA) is inherited from only one of the 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 irfd ;e4uw79 k:).ayoq0nsyqe bz86ae n 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 thefc, lp505 :s a,tzgzjhwye 6i) cell cycle in four samples of lung tissue from four paehz sz:)c lip5gyf06t,5 jw ,atients. Which tissue has the lowest mitotic index?

  The diagram shows the dominanf* if3k6qhag5 t cyclin/CDK complexes at different time points in faf h5ik3*g6 qthe cell cycle. Which cyclin/CDK complex activates DNA replication machinery?

  Studies have shown that genes such as C-. 7kgzrv:/syiqlxh4 l mb /8g 1a2molyclin Dependent Kinase 3 (CDKN3) are highly overexpressed in cervical tumours. 7k/- 8mi24/ v.zy:rb ls xgoamh gq1ll


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 cycuf)/kt8tq ujo)+s pxn(voiz) i k+ )2vlin E the highest during the cell cycle ?