www.vietmaths.com I T BO Cu1: Gii thch ngn gn TS cc phn t nc li lin kt hyro vi nhau? VS cc phn t nc li to ra cc lin kt hyro? Nhng tnh cht c o no ca nc l kt qu ca khuynh hng cc phn t nc to lin kt hyro vi nhau? Mt phn t nc nc lin kt ti a bao nhiu phn t nc khc? Cc phn t nc to nn cc cu ni hyr bi v chng phn cc. Cc c im c o ca phn t nc do cc cu ni hyro to nn l s c kt, sc cng mt ngoi, kh nng tch v to nhit ln, im si cao, th rn (ng bng, ho ) c t trng nh hn th lng v c tnh ho tan. Mt phn t nc lin kt ti a 4 phn t nc khc. Cu2: Miu t 2 phng thc cc phn t nc trong c th gip gi thn nhit n nh. - Cn mt lng nng lng ln mi ph v c cc cu ni hyro ca nc lm cho nc trong c th nng ln t nhiu, c tnh ny khin nc trong c th va ngn khng cho thn nhit gia tng qu mc, va cho php nc trong c th tch lu c nhiu nhit, b li nhit lng b mt khi thn nhit hi b gim, phc hi li mc cn bng n nh. - Khi bay hi, nc phi ly nhit lng ph v cc lin kt hyro nn khi c th nng ln th mt phn nc trong c th bay hi (thot m hi) ly nhit ho hi t c th, lm h thn nhit xung mc c. y l c ch lm lnh do bc hi. Cu3: So snh lin kt ho tr v lin kt ion. Lin kt ho tr trong mt phn t hnh thnh khi cc nguyn t dng chung mt s cp electron lp electron ngoi cng t mc bo ho. Lin kt ion trong mt phn t hnh thnh ion dng , nguyn t khc thu electron mang in tch m tr thnh ion m hai ion m dng hp dn ln nhau. Cu4: ng vt thu nng lng qua mt lot phn ng ho hc m cc cht tham gia phn ng l ng n (C6H12O6) v oxy (O2). Qu trnh ny sn sinh ra nc v ioxyt cacbon nh l sn phm thi. Cc nh nghin cu mun bit oxy trong CO2 l t ng hay t O2. TS c th dng cht ng v phng x gii quyt vn ? - Cho chut n ng hoc th kh oxy c cha oxy ng v phng x ri sau quan st kh CO2 do chut th ra c cha oxy phng x hay khng. Cu5: Cc cu sau y ng hay sai. (Cha sai thnh ng) A. Mui, nc, cacbon l hp cht. S- cc thnh phn ch c mui v nc. B. Cc nguyn t trong mt phn t nc gi nhau bng cc electron dng chung. C. Nc ni v cc phn t nc trong nc xp st nhau hn l trong nc thng. S- cc phn t ch tip tc tch ra. Cu6: Chn cu ng: 1. V tr no trong cu trc ba chiu ca mt protein m bn d tm thy mt axit amin k nc ca nhm R? A. Ti c 2 mt ca chui polipeptid. 1

www.vietmaths.com B. Ti bn, ngoi bn trong. C. Ti lin kt ho tr vi mt nhm R khc. D. bn trong, cch bit vi nc. x E. Ti lin kt ho tr t nhm amin ny vi axit amin k tip. 2. Enzim amilaza tu tng l mt protein c chc nng nh vo cc phn t tinh bt trong thc n phn gii chng thnh cc isacarit. Amilaza khng th phn gii c xenluloza. Ti sao khng th? A. Xenluloza l mt cht bo, khng phi l mt hyrat cacbon nh tinh bt. B. Cc phn t xenluloza ln hn rt nhiu. C. Tinh bt c lm bng glucoza, xenluloza c lm bng cc loi ng khc. D. Lin kt gia cc ng trong xenluloza mnh hn rt nhiu. E. Cc ng trong xenluloza lin kt mt cch khc nhau, khin cho xenluloza c hnh dng khc nhau. x 3. Thiu phospho trong t s gy kh khn c bit cho cy trong ch to: A. ADN B. Protein C. Xenluloza D. Cc axit bo E. Sacaroza. 4. Cc phn t lipit khc vi cc i phn t sinh hc khc v: A. Chng di hn nhiu. D. Khng cha cacbon. B. Khng phi thc th l polime.* E. Cha cc nguyn t nit. C. Khng c hnh dng chuyn ho. Cu7: Cc cu sau y ng hay sai? (Cha cu sai thnh cu ng). 1. ng lu thng trong mu ta ch yu l isacarit. S - ng n. 2. Cht bo trong du ng khng cha hyro v nhiu ni i hn so vi cht bo trong b. 3. Cc gen c to thnh t ADN. 4. Hocmon testosteron l mt steroit - mt loi protein. S - dng cht bo. 5. Khi cc axit amin lin lin kt vi nhau to thnh mt polypeptit, nc sinh ra nh mt cht thi. 6. Cun ba chiu ca phn t protein l kt qu t s hp dn v lin kt gia cc nhm R. 7. Khi mt protein bin tnh, cu trc bc mt ca n l bc cu trc d b ri lon nht.s 8. Cc phn t cht bo tch lu nng lng trong TB. Cu8: K 4 loi lipit khc nhau v m t ngn gn chc nng tng loi. - Triglixerin: tch lu nng lng. - Photpholipit: to mng. - Sp: to cc lp v khng thm nc. Cc steroit - mt thnh phn ca mng TB, tc ng nh hocmon. Cu9: Gii thch ti sao un nng, thay i pH, v nhng thay i ca mi trng c th vi phm chc nng ca protein? Cc lin kt yu khng gi n nh cu trc ba chiu ca protein b ph v v protein b bung ra. Chc nng ph thuc vo hnh dng cu trc nn khi cu trc protein b sai lch s khng cn thc hin c chc nng c trng c. 2

www.vietmaths.com Cu10: TS t 20 loi axit amin khc nhau mt TB c th tng hp c nhiu loi protein? Trong v vn kh nng, TS TB nhn bit c ng lc no phi tng hp protein no? - Do..... - Cc gen xc nh cc mch m gcADN, biu th cc chui c bn ca protein trong TB. Cu11: Khi bn n mt cc ng sacaroza vo rut non s b phn gii thnh ng n mnsacarit (Glucoza v fructoza) sau s hp th vo mu bn. Bt u t phn t disacarit minh ho y chng minh ti sao n li phn chia thnh glucoza v fructoza c? Phn ng ny gi l phn ng g? y l phn ng thu phn, phn ng cn s dng nc. Cu12: Chc nng quan trng nht ca ng phn trong TB l g? 1. thu c m t glucz. 2. ly nng lng t glucz mt cch t t. 3. Cho php hirat cacbon thm nhp vo chu trnh Crebs.* 4. C kh nng phn chia phn t ng glucz thnh 2 mnh. Cu13: Cu khng nh no di y l khng ng? A. S phosphoryl ho ADP xy ra trong mng thilacoit. B. ATP c hnh thnh khi proton khuch tn qua ATPsynthase. C. ATP c tiu th trong qu trnh phn ng ti. D. NADPH v ATP tm thy photosystem II.* Cu14: Mt con chut c cho th khng kh c cha oxy ng v phng x. Trong con chut ny nguyn t oxy "dnh du" u tin xut hin u? A. Pyruvat. B. CO2; C. Acetyl - CoA; D. Nc.* Cu15: Trao i cho thng xy ra trong iu kin no di y? A. Hnh thnh tnh nguyn bo. B. Hnh thnh bo t dng x.* C. Hnh thnh trng b phn trng c l gan. D. Hnh thnh th cp t mt thn cy du ty. Cu16: Ngun nng lng trc tip s dng to nn hu ht cc ATP t bo ng vt l g? A. Chuyn nhm phosphat t sn phm phn hu glucz sang ADP. B. S di chuyn ca ion hyr qua mt mng c bit.* C. S phn hu glucz thnh 2 phn t pyruvic. D. S di chuyn in t theo chui vn chuyn in t. Cu17: Mt trong cc hu qu m tnh ca vic lm dng khng sinh l: A. S thch nghi ca ngi dng vi nng thuc ngy cng gia tng. B. Kch thch s sinh sn khng th. C. Chn lc cc dng vi khun khng khng sinh.* D. Tng tn s t bin, thm ch gy nn ng th. Cu18: T php lai gia mt ong c vi mt ong cha, cho cc kiu gen F1 nh sau: Ong c: AB, Ab, aB, ab. Ong ci: AaBb, Aabb, aaBb, aabb. 3

www.vietmaths.com Kiu gen ca b m l g? A. aaBb x Ab; B. AaBb x ab;* C. AAbb x aB; D. AaBb x Ab. Cu19: Vai tr ch yu ca ATP trong vic truyn thn kinh l: A. c ch vn chuyn Na+ v K+ qua mng. B. Cm ng th nng hnh ng. C. Tng th nng hnh ng khi n c hnh thnh. D. Duy tr th nng ngh.* Cu20: Mt phn t phi qua bao nhiu lp mng i t bn trong dip lc t ti cht nn ty th? A. 3; B. 5;* C. 7; D. 9. Cu21: Cc cht c th c vn chuyn qua mng ngc gradent nng ca chng v: A. Mt s protein l cc phn t vn chuyn ph thuc ATP.* B. Mt s protein hot ng nh cc knh qua cc phn t c bit c th i vo t bo. C. Lp lipit kp cho php nhiu phn t nh thm thu qua n. D. Lp lipit kp l k nc. Cu22: Mt loi nm mt kh nng phn gii tinh bt trong mi trng nui cy nht nh. Nguyn nhn dn n hin tng l g? 1. Nm ny khng cha amilase. 2. Enzim amilase trong si nm khng c tit ra. 3. C mt s cht lm gin on qu trnh phn gii tinh bt ca nm. 4. C cht h hp i vi nm l cacbohydrat. Cu tr li ng l: A. Ch c 1, 2; * B. Ch c 3, 4; C. 1, 2, 3; D. 1, 2, 3, 4. Cu23: Enzim no di y khng c ngi? A. ADNpolimerase; B. Hexokinase; C. Chitinase;* E. ATP-synthetase. Cu24: Ci no di y biu th s khc bit gia t bo thc vt v t bo ng vt trong qu trnh nguyn phn? 1. Phn chia tm ng; 2. S phn chia t bo cht; 3. Chc nng ca thoi v sc. 4. S c mt ca trung t. Cu tr li ng l: A. 1, 2; B. 1, 4; C. 2, 4; * D. 3, 4. Cu25: in du x vo v tr thch hp ch rng mi cu khng nh di y lin quan n quang hp thc vt l ng hay sai: ng Sai A. S quang phn li xy ra Photosystem I: x B. Oxy c gii phng: x C. NADH2 c hnh thnh: x Cu26: Nu cu khng nh l ng cho c lc lp v ty th, th hy nh du cng (+), nu sai th nh du tr (-). A. Cha protein.+ B. Cha cc Coemzim lin kt vi cc ion hyr.+ C. Cha ion K+.+ 4

www.vietmaths.com D. Khng c ADN.E. C th to ra ATP.+ F. C th to ra oxy.II. THC VT Cu1: U 6 ng nghim vi thanh phn khac nhau ( nh bang di). T 3 ng trong 6 ng o co kh CO2 bay ra trong qua trnh u. Hay ch ra o la nhng ng nao? Giai thch. ng Thanh phn 1 Glucz + Cac TB ng nht. 2 Glucz + ty th. 3 Glucz + TB cht khng co cac bao quan. 4 Axit piruvic + cac TB ng nht. 5 Axit piruvic + Ty th. 6 Axit piruvic + TB khng co cac bao quan. A: 1,4,5 Cu2: th trn hnh ve biu th mi quan h gia nng auxin va ln cua t bao trong m thn. ng cong nao trong cac ng trn th co nhiu kha nng biu din s phu thuc gia ln cua TB chi bn vi nng auxin II III IV

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www.vietmaths.com I

Pham vi ln cua TB

Nng auxin

A: I. Cu3: S di y minh hoa qua trnh h hp (ng phn) va chu trnh Creb. Trong cac giai oan nao co s tham gia cua 2 loai enzim decarboxylase va dehydrogenase 6 C1 3 C2 2 C 4 6 C 4 3 C A:2,3. 5 Cu4: Co 10 hang muc lit k di y lin quan n th a cho. Hay C xac nh hang muc nao phu hp vi th? Giai thch.Kch thch tng trng

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www.vietmaths.comNu Thn

c ch

R Nng auxin

Thn khng phan ng vi auxin. R khng phan ng vi auxin. R va thn phan ng rt khac nhau vi auxin. Nu khng phan ng vi auxin. R tit ra auxin va do o no t bao v chung. Nng auxin cao lam tng s phat trin cua r. Cho thm auxin lun lam tng cng s phat trin cua thn. S phat trin cua r cn mt lng auxin t hn so vi s phat trin cua thn 9. S phat trin cua r c ch s phat trin cua thn. 10. S phat trin cua r c tng cng bi s phat trin cua thn. A: 3, 8. Cu5: Vic giam lng oxy lam tng cng ng phn (phn giai glucz) v: 1. Co s gia tng nng ADP trong TB.* 2. Co s gia tng nng NAD+ trong TB. 3. Co s gia tng nng ATP trong TB. 4. Co s gia tng nng peroxides va cac gc t do. Cu6: ng knh thn cy ng c xac nh bi s hoat ng cua cac loai m sau: 1. S cp.* 3. S cp va th cp. 2. Th cp. 4. u tin la m s cp sau o n m th cp. Cu7: S tng trng s cp (day ln) cua thn cy la c trng cho: 1. Ru, TV hat trn, TV hat kn. 2. Cy mt la mm, TV hat kn, TV hat trn. 3. Hat kn mt va hai la mm. 4. Hat trn va hat kn hai la mm.* Cu8: Than nu c tao ra t nhng thc vt bc cao nao? 1. Thc vt la kim. 3. Dng x. 2. TV hat trn.* 4. Thc vt hat kn. Cu9: Giberellin la: 1. Photpholipit. 2. Triaxilglyxerol. 3. Sap. 4. Steroid. 5. Terpin.* Cu10: Hay chon nhng c im khng nh gia thuyt ni cng sinh trong s hnh thanh luc lap: 1. Cac c quan t co mt lp mang. 2. Cac c quan t co hai lp mang. 7

1. 2. 3. 4. 5. 6. 7. 8.

www.vietmaths.com 3. Cac b may DT ring dang phn t ADN dang vong. 4. Khng co b may ring cua mnh. 5. Co ribxm khac vi ribxm cua TB cht v cu truc. 6. Co ribxom khng khac vi riboxom TBC v cu truc. A. 1. 4, 5. B. 2, 4, 6. C. 1, 3, 6. D. 2, 3, 5.* E. Khng co t hp cu tra li nao ung. Cu11: Qua trnh h hp sang khng: A. Xay ra vao ban ngay. B. San xut photphoglucolat. C. Cn oxy. D. Tao ADP. Cu12: ADN cua vi khun Mycobacterium tubeculosis cha 18% Adenin ty l lng Guanin + Xitizin la: A. 18%; B. 12%; C.36%; D. 64%*; E. 82%. Cu13: phn nao cua luc lap ngoai anh sang co pH thp nht? A. Stroma. B. Cht nguyn sinh. C. Khng gian c gii han bi cac lp mang tilacoit.* D. Khng gian gia mang ngoai va mang trong. Cu14: Roi cua sinh vt nhn s c chuyn ng bng nng lng cua: A. ATP. B. Th nng in hoa hoc.* C. S photphoryl hoa. D. Phosphoendpiruvate. Cu15: S truyn thng tin di truyn t vi khun nay sang vi khun khac nh vi rut c goi la: A. S chuyn v tr. B. Bin nap. C. Chuyn dang. D. Tai nap.* Cu16: Mi trng bn trong Lysosome la: A. Axit hn so vi mi trng TBC.* B. Kim hn so vi mi trng TBC. C. Co pH nh trong TBC. D. i khi axit hn nhng co luc lai kim hn. Cu17: S giam mc kch thch cua cac TB thn kinh la: A. Thay i th nng ngh cua TB v gia tr m.* B. Thay i th nng mang t gia tr m sang gia tr dng. C. Thay i tnh hiu th nng mang TB t gia tr dng sang gia tr m. D. Tt ca u sai. 8

www.vietmaths.com Cu18: Cac lizoxom s cp c tao ra : a. T bao cht. c. B may Golgi.* b. Nhn. d. Trung tm TB. Cu19: Cac protein c tng hp li ni cht hat c vn chuyn n: a. Lizoxom. c. Dch trong sut cua TB. b.Ty th. d. Lap th. e. B may Golgi.* Cu20: Trn NST cac gen r-ARN nm vung: a. im cui cua NST. b. Eo s cp. c. Tm ng. d. oan th kem cua NST. e. Eo th cp.* Cu21: Cai g lin kt Ribxm vi li ni cht? a. Glucz. b. Trnh t u N cua protein.* c. Trnh t u C cua protein. d. Lipit. e. Cac ion. Cu22: Cac cht c ch canh tranh vi enzim co: A. Cu tao ging vi phn t Enzim. B. Cu tao ging vi phn t c cht*. C. Cu tao ging vi gen ma hoa enzim o. D. Co kha nng lin kt enzim va c cht. E. Lun co kha nng gy bt hoat enzim. Cu23: Khi c chiu sang cy xanh giai phong ra O2. Cac phn t O2 o c bt ngun t: A. S kh CO2. B. S phn huy nc.* C. Phn giai ng. D. Quang h hp. E. Hai trong s cac kha nng trn co th ung trong nhng iu kin khac nhau. Cu24: Qua trnh sinh l nht nh xay ra trong cy ch sau khi cy c chiu sang vi mt ph anh sang y u hoc bng anh sang o. Anh sang n sc khng th tao ra c hiu qua sinh l nay. Da trn nguyn l o, ngi ta co th ch i qua trnh sinh l nht nh iu khin qua: A. Dip luc. B. Sc t flavonoid. C. Phytochrome.* D. Auxin hoc gibberelin. E. Thng tin a cho khng u chon cu tra li.

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www.vietmaths.com Cu25: Sau cuc chay maratng, co s thiu hut O2 trong c cua vn ng vin. Sau mt thi gian ngh ngi qua trnh nao di y se xay ra trong c th vn ng vin vi cng cao? A. Bin i axit pyruvic thanh lactic. B. Chuyn hoa lactic thanh axit pyruvic. C. Tch luy NADH.* D. ng phn. E. Hai trong s cac cu trn. Cu26: Liu co kha nng cac TB ring bit cua mt loai vi khun nht nh co mt s lng phan t plasmid khac nhau khng? A. Khng, mi TB ch cha mt phn t plasmid. B. Co, Nhng ch khi co cac loai plasmid khac nhau. C. Co, nhng ch khi nu vi khun c nui cy trong cac iu kin khac nhau. D. Co, v rng s tai sinh cua cac plasmid khi c kim tra mt cach cht che.* E. Co, nhng ch ung i vi mt s dong vi khun khac nhau. Cu27: Penicillin khng lam hai cac TB vi khun nhng nu co mt penicillin th vi khun se khng tng s lng. T cac thng tin nay, ngi ta co th cho rng penicillin a c ch: A. S phin ma. B. Sinh tng hp protein. C. Sinh tng hp cac thanh phn cua TB. D. S sao chep ADN. E. Co nhiu cai phu hp vi thng tin nu trn hn la ch co mt trong s im nu trn. Cu28: Cac TB m seo c nui cy vai gi trong mi trng chnh, cac cht cn thit trong o co mt cht c anh du phong xa. Sau o cac TB c c nh soi di knh hin vi. Bng phng phap phong xa t ghi, ngi ta thy cht phong xa tp trung trong Nhn TB, Ty th va Luc lap. Hp cht c anh du phong xa co th la: a. Axit amin. b. Uridin. c. Timin.* d. Glucz. e. Lipit. Cu29: Poliriboxm co th c tm thy trang thai t do trong TBC hoc gn vi mang li ni cht. Yu t nao qui nh mt mARN c dch ma trn cac ribxom "t do" hay trn cac riboxom lin kt vi li ni cht? A. Phu thuc vao trt t axit amin cua chui polipeptit do mARN o ma hoa.* B. Nu mARN co ui PoliA th no se dch ma cac riboxom lin kt vi li ni cht. C. Nu mARN co mt mu u 5' th no se dch ma riboxom lin kt vi li ni cht, con nu khng co mu u 5' th c dch ma riboxom t do. 10

www.vietmaths.com D. Ch co cac mARN ngn hn 1000 Nu mi co th dch ma cac riboxom t do, con cac mARN dai hn th dch ma cac riboxom lin kt vi li ni cht. E. Thc t phu thuc vao loai TB, trong nhiu TB nht nh mARN chu yu c dch ma cac riboxom t do, trong khi o loai TB khac hu ht lai c dch ma tai riboxom lin kt vi li ni cht. Cu30: Cac cht di y u co mau. i vi cht nao th mau sc khng lin quan g n chc nng cua no? A. Chlorophyll. B. Phytochrome. C. Vitamin A. D. Hmoglobin.* E. i vi tt ca cac cht trn mau sc u lin quan n chc nng cua chung. Cu31: Restrovirus gy bnh AIDS goi la HIV. ARN cua virut nay trong TB vt chu nh enzim sao ma ngc tao thanh ADN. iu khng nh nao di y la ung? A. ADN virut c tng hp trong TB nhim HIV. B. ARN virut c tng hp trong TB nhim HIV. C. ADN c dch ma thanh protein virut. D. A va B ung. E. Ca A, B, C u ung.* Cu32: Ngi ta gi khoai ty 1 tun trong khng kh sach, sau o gi mt tun trong nit sach ri lai gi 1 tun trong khng kh sach. Ngi ta o CO2 giai phong ra trong th nghim. Trn th la kt qua:Lng CO2 c giai phong

Lng CO2 c tao thm va c thai ra tun th 3 co th rtao ra t: A. Etanol. B. Etanal. C. Axit lactc. D. NADH2. III. VI SINH VT CU1: ADN ca vi khun Mycobacterium tubeculosis cha 80% Adenin. T l lng G + X l: a. 18%. b. 12%. c. 36%. d. 64%.* CU2: Ribxm trong TBC ca TB nhn thc c: 11

Thi gian

www.vietmaths.com a. b. c. d. Cu to v kch thc ging vi khun. Kch thc ln hn vi khun nhng cu trc tng t.* Kch thc ging vi khun nhng cu trc khc. Kch thc b hn vi khun c cu trc khc.

CU3: Ribxm c cha: a. ARN v protein.* b. ARN, protein v lipit. c. ARN, lipit v glucz. d. ADN, protein v lipit. CU4: Cc lizoxom s cp c to ra : c. T bo cht. c. B my Golgi.* d. Nhn. d. Trung tm TB. CU5: Cc protein c tng hp li ni cht ht c vn chuyn n: c. Lizoxom. c. Dch trong sut ca TB. d. Ty th. d. Lp th. e. B my Golgi.* CU6: Trn NST cc gen r-ARN nm vng: f. im cui ca NST. g. Eo s cp. h. Tm ng. i. on th km ca NST. j. Eo th cp.* CU7: Ci g lin kt Ribxm vi li ni cht? f. Glucz. g. Trnh t u N ca protein.* h. Trnh t u C ca protein. i. Lipit. j. Cc ion. Cu8: Cc TB m so c nui cy vi gi trong mi trng chn, cc cht cn thit trong c mt cht c nh du phng x. Sau cc TB c c nh soi di knh hin vi. Bng phng php phng x t ghi, ngi ta thy cht phng x tp trung trong Nhn TB, Ty th v Lc lp. Hp cht c nh du phng x c th l: a. Axit amin. b. Uridin. c. Timin.* d. Glucz. e. Lipit. Cu9: Trt t ng n ca cc cu trc theo th t t n gin (t cu trc cha mt s lng t nht cc loi phn t Protein khc nhau) n cu trc phc tp nht (cu trc cha mt s lng t nht cc loi phn t Protein khc nhau) c a ra trong cc cu tr li sau: a. Tc nhn gy bnh b in, HIV, riboxom ca SV nhn thc, ty th.* b. Riboxom ca SV nhn thc, HIV, tc nhn gy bnh b in, ty th. c. Tc nhn gy bnh b in, HIV, ty th, riboxom ca SV nhn thc. d. HIV, tc nhn gy bnh b in, riboxom ca SV nhn thc, ty th. e. Tc nhn gy bnh b in, riboxom ca SV nhn thc, HIV, ty th. 12

www.vietmaths.com CU10: Poliriboxom c th c tm thy trng thi t do trong TBC hoc gn vi mng li ni cht. Yu t no qui nh mt ARNm c dch m trn cc riboxom "t do" hay ribxom lin kt vi li ni cht? a. Ph thuc vo trt t axit amin ca chui polipeptit do ARNm m ho.* b. Nu ARNm c ui poli (A)- th n s dc dch m cc riboxom lin kt vi li ni cht. c. Nu ARNm c mt m u 5' th n s c dch m riboxom lin kt vi li ni cht, cn nu khng c m u 5' th c dch m bi cc riboxom t do. d. Ch c cc ARNm ngn hn 1000 nu mi c th dch m c cc riboxom t do, cn cc ARNm di hn th dch m cc riboxom lin kt vi li ni cht. e. Thc t tu thuc vo loi TB. Trong nhiu TB nht nh c cha ARNm ch yu c dch m cc riboxom t do. Trong khi loi TB khc hu ht li c dch m ti riboxom lin kt vi li ni cht. CU11: Di y l s chu trnh TB. Mt ngi mun xc nh di thi gian pha S. iu ny c th thc hin c nh cht R c nh du bng triti vo c th c TB ang phn chia. Cht no trong s cc cht di y tng ng vi cht R?G1

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CU12: Hy xem chui phn ng tng hp: E3 X E1 A E2 B C E4 Y Nu enzim 4 b hng th trong trng hp ny phi thm g vo mi trng trong trng hp t dng vi khun pht trin bnh thng? a. X. b. A. c. X v C. d. C. e. Y* CU13: Cho bng t l % baznit cc loi khc nhau: Loi Aenin Guanin Timin Xitozin Uraxin 1 21 29 21 29 0 2 29 21 29 21 0 3 21 21 29 29 0 4 21 29 0 29 21 5 21 29 0 21 29 Hy cho bit vt liu DT ca cc loi trn? CU14: Cc gen ca SV nhn thc khng th thc hin chc nng bnh thng nu chng c tch dng vi khun. iu g di y khng phi l nguyn nhn ca hin tng ? a. Khng c kh nng ct b intron. b. Cc enzim endonuclease ph hu TB vi khun. 13

www.vietmaths.com c. ARNpolimerase ca VK ph hu qu trnh nhn bit gen khi ng. d. Cc phn lin kt ribxom khc bit nhau. e. S dng m DT khc nhau.* CU15: phn no ca lc lp ngoi nh sng c pH thp nht? E. Stroma. F. Cht nguyn sinh. G. Khng gian c gii hn bi cc lp mng tilacoit.* H. Khng gian gia mng ngoi v mng trong. Cu14: IV. DI TRUYN CU1: Trnh by nhng nhng tiu chun ca vt cht di truyn? Vt cht DT trong TB v c th phi c y cc tiu chun c bn sau y: 1. Mang TTDT, c trng ca tng loi: Tnh cht ny bao gm: *Tnh cht ca gen cu trc: VCDT phi c kh nng, bng cch ny hay cch khc, c trng cho cu trc ca cc phn t khc trong TB. VD: Nu tha nhn cc gen no qui nh cu trc protein, th VCDT phi c kh nng m ho mt cch chnh xc mt khi lng ln cc on khc nhau mang axit amin trong cc chui polypeptit. *Tnh cht ca gen iu ho: Gen iu ho cha thng tin p ng yu cu iu ho hot ng trong c th. Mt s vng ca ADN trn Operon, c gen iu ho v gen khi ng, hot ng nh "kho hm" ngt hoc m hot ng ca gen. Cc c im ring ca tng loi, nh pht trin phi, phn ho c quan, c sai khc gia loi ny vi loi khc, u c chng trnh ho v mt DT. VCDT phi c kh nng, bng nhiu cch, iu ho hot ng ca gen. 2. Tnh t sao, c kh nng ti bn mt cch chnh xc: y l kh nng hnh thnh cc bn sao, truyn li cho TB con trong qu trnh phn bo, vi tt c TTDT ca loi cha trong . Qua qu trnh nguyn phn, mi TB con c hnh thnh, nhn mt bn sao ton b TTDT. Qua gim phn VCDT gim i mt na mi giao t. 3. TTDT cha trong VCDT phi c s dng to ra nhng phn t cn thit cho TB. 4. VCDT phi c kh nng bin i. C ch t sao ca VCDT c th chnh xc n mc cc sai st him xy ra, nhng khng phi l tuyt i chnh xc khng xy ra t bin. Chnh B ca VCDT l mt ngun ch yu ca bin d, rt cn cho tin ho ca cc loi. CU2: ADN c nhng c im g tho mn l vt mang TTDT? *ADN tha mn cc yu cu i vi vt cht di truyn: 14

www.vietmaths.com Cha v truyn t thng tin di truyn: i hi trc tin i vi vt cht DT l c kh nng cha thng tin DT. ADN c chiu ngang th gii hn nhng chiu di th khng hn ch. Trnh t sp xp cc Nu theo chiu di c th phn nh nhng thng tin nht nh. ADN c 4 loi Nu nhng s trnh t khc nhau l con s khng l. Kh nng cha thng tin lm cho phn t ADN l phn t di nht trong t nhin. Ngoi ra n cn c m rng do cc thay i cu trc, do gy ni li v lp ghp gia cc on ADN. Thng tin cha trn ADN c s dng v hin thc ha nh cc cht trung gian ARN, ri n tng hp cc protein l nhng cng c phn t thc hin chc nng ca TB. T sao chp chnh xc: M hnh Watson - Crick cng tha mn mc l tng yu cu th 2 ca vt cht di truyn. Chui xon kp gm 2 si b sung cho nhau theo nguyn tc A-T v GX , lm cho phn t nh c mt bn m v mt bn dng. Mi bn c th lm khun to ra bn kia t mt phn t ban u c 2 phn t ging ht n. C kh nng bin d di truyn: Trn phn t ADN c th xy ra nhiu bin i. Cc bin i c th c di truyn. VD: cp A-T trn ADN c thay bng cp G-X th s thay th c truyn cho cc phn t con. C tim nng t sa sai: Cc nh di truyn hc cn pht hin thm mt tnh cht na ca ADN l tim nng t sa sai. Do cu trc mch kp nn sai hng mt mch c th b ct b v da vo mch nguyn vn lm khun tng hp li cho ng. CU3: Nhng bng chng chng minh ADN l vt mang thng tin DT: * Cc bng chng chng minh ADN l cht di truyn: a/ Cc chng minh gin tip: ADN c trong tt c TB sinh vt, ch gii hn trong nhn v l thnh phn ch yu ca NST. Mt cu trc TB mang nhiu gen xp theo ng thng. Tt c cc TB sinh dng ca bt k mt loi sinh vt no u cha mt lng ADN rt n nh khng ph thuc vo s phn ha chc nng hay trng thi trao i cht. Ngc li ARN bin i ty thuc vo trng thi sinh l TB. S lng ADN tng theo s bi th ca TB TB n bi ADN s lng ADN l 1 th TB sinh dng lng bi s lng ADN tng gp i. Tia t ngoi c hiu qu gy t bin cao nht bc sng 260nm; y chnh l bc sng m ADN hp th tia t ngoi nhiu nht. b/ Hin tng bin np: Truyn thng tin di truyn nh ADN. Hin tng bin np c Gripffith pht hin Diplococcus Pneumoniae vo nm 1928. Vi khun ny c 2 dng khc nhau: Dng S, gy bnh c v TB bng polisaccharid cn tr bch cu ph v TB. Dng ny c khun lc lng mc trn mi trng aga. Dng R, khng gy bnh, khng c v bao, to khun lc nhn.

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Th nghim bin np chut. Tim vi khun S sng gy bnh cho chut chut cht. Tim vi khun R sng khng gy bnh chut sng. Tim vi khun S b un cht cho chut chut sng. Hn hp vi khun S b un cht trn vi vi khun R sng em tim cho chut chut cht. Trong xc chut c vi khun S v R. Hin tng trn cho thy vi khun S khng th t sng li c sau khi b un cht, nhng cc TB cht ny truyn tnh gy bnh cho TB R. Hin tng ny gi l bin np. Nm 1944, T.Avery, Mc Leod v Mc Carty tin hnh th nghim xc nh r tc nhn gy bin np. Nu s l TB S bng proteaza hoc ARNaza hot tnh bin np vn cn. Chng t protein v ARN khng phi l tc nhn gy bin np. Nhng nu TB S cht b s l bng ADNaza th hot tnh bin np khng cn na. Chng t ADN l tc nhnbin np. Kt qu th nghim c th tm tt nh sau: ADN ca TB S + cc TB R sng chut chut cht ( c c S +R). Vy hin tng bin np l mt minh chng sinh ha xc nhn rng ADN mang tn hiu di truyn. c/ S xm nhp ca ADN virut vo vi khun. Nm 1952, A.Hershey v M.Chase tin hnh th nghim vi Bacteriophage T2 xm nhp vi khun E.coli. Th nghim ca A.Hershey v M.Chase nhm xc nh xem phage nhim vi khun bm cht no vo TB vi khun: ch c ADN, ch protein hay c hai. V ADN cha nhiu photpho nhng khng c lu hunh. Cn protein cha lu hunh nhng khng cha photpho, nn c th phn bit gia ADN v protein nh cc ng v phng x P v S. Phage c nui cy trn mi trng cha ng v phng

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www.vietmaths.com x P32 v S35 .

Hnh 5:Vt cht di truyn ca phage l ADN. S35 xm nhp vo protein cn P32 vo ADN ca phage. Phage nhim x ny c tch ra, em nhim vo vi khun khng nhim x. Cho phage nhim trong mt khong thi gian bm vo vch TB vi khun v bm cht no vo trong TB, ri dung dch c lc mnh v li tm tch ri TB vi khun ra khi phn phage bm vo bn ngoi vch TB. Phn tch phn nm ngoi vi khun cho thy cha nhiu S35 (80%) nhng t P32, chng t phn ln protein v ca phage nm ngoi TB vi khun. Phn tch phn trong TB vi khun thy chng cha nhiu P32 (70%) nhng t S35, chng t ADN c bm vo trong TB. Th nghim ny chng minh trc tip rng ADN ca phage xm nhp vo TB vi khun v sn sinh to ra th h phage mi mang tnh di truyn c kh nng tip tc nhim cc vi khun khc. CU4: Hy cho bit VCDT ca virut. + VCDT l ADN: VR k sinh ng vt v thc khun th th mang ADN. Phn ln cc thc khun th u cha ADN 2 si, nhng cng c mt s loi mang 1 si. VD: h gen ca phi 174 mang 5375 Nu nmg trong mt si ADN vng. + VCDT l ARN: ch yu thc vt. CU6: VS nhn thc, a phn ARN c tng hp trong nhn u tri qua 3 bin i trc khi chuyn t nhn vo TB cht. Nhng bin i no s gip bo v ARN khi b phn hu bi cc enzim nuclaza? Gn ui 7-methyl-guanin vo u 5'. Gn ui polyA vo u 3'. CU7: Nhng c im no sau y cho php xc nh mt TB l ca VS nhn thc hay ca SV nhn s? + Vt liu DT tn ti dng phc tp ca axit nuclic v protein. 17

www.vietmaths.com + Vt liu DT c phn tch khi phn cn li ca TB bng mt ro cn bn thm. + Vt liu DT l ARN. + Vt liu DT l ADN dng vng. + N c vch TB. + TB di ng. + N s dng H2S lm ngun nng lng.

1/ Theo quan im hin i th VCDT phi c nhng tiu chun no sau y? Mang thng tin DT c trng cho loi. Phi c kh nng bin i. C kh nng t nhn i chnh xc. C kh nng m ha nhng sn phm ca TB. C ABC. 2/ Cu trc ca VCDT cc c quan t trong TBC c phn nh trong cu trc no di y? L nhng ADN kp mch thng. L nhng ADN n mch vng. L nhng phn t ARN. L nhng phn t ADN kp mch vng. Khng c cu trc n nh. 3/ Trong nhng th nghim ni ting sau dy ca Griffth, th nghim no cho bit c nhn t bin np lm bin ph cu khun dng lnh (R) thnh dng c (S)? R tim vo chut chut sng. S tim vo chut chut cht S (lm cht bng nhit) tim vo chut chut sng. S (lm cht bng nhit) trn vi R tim vo chut chut. C A, B, C, D. 18

www.vietmaths.com 4/ Sau nhng th nghim ca Griffth, Avery v cng s nghin cu su hn theo hng v lm sng t nhiu vn , a ra nhiu kt lun. Kt lun c ngha nht l: Ggiffth c ng gp to ln vo min dch hc. Nhn t bin np trong th nghim ca Griffth l ADN. Vt cht DT vi khun l ADN. nhit cao no vi khun cht nhng ADN vn cn hot tnh. Dng enzim ph b lp v ca vi khun cng thu c kt qu tng t nh s l bng nhit . 5/ Trn i tng virut khm thuc l (TMV), cc nh DT hc dng li ARN v v protein ca 2 ni virut khc nhau A v B. c tch ra bng phng php ha sinh, ri cho: ARN ca ni A trn vi protein ni B th to c virut gy m kiu A. ARN ca ni B trn vi protein ni B th to c virut gy m kiu B. Gi tr ln nht ca th nghim l chng minh c: Cu trc ca virut TMV gm li ARN bc v protein. Li ARN v v protein d dng c tch ra bng phng php ha sinh. Vt liu DT ca virut m thuc l l ARN. ARN l nhn t quyt nh c im ca vt khm. V ca virut ny c th lp c vo li ca virut kia. 6/ S sau y m t th nghim ca Hershey - Chase trn thc khun th (TKT) v E.coli:

Vi DTH gi tr ln nht ca th nghim ny l ch n chng minh c: Ch c li ADN xm nhp vo E.coli. Li ca TKT c bn cht ADN cn v c bn cht protein. ADN ca TKTc th c nhn ln trong E.coli m khng cn v. Vt cht DT ca TKT l ADN. 19

www.vietmaths.com T li ADN, TKT c th t to v nh E.coli. 7/ Dng bng chng no sau y chng minh c vt cht DT sinh vt nhn chun l ADN? Trong TB soma ca mi loi sinh vt lng ADN n nh qua cc th h. Trong TB sinh dc lng ADN ch bng 1/2 so vi lng ADN TB soma. ADN hp th tia t ngoi bc sng 260nm ph hp vi ph gy t bin mnh nht. Nhng bng chng trc tip t k thut tch v ghp gen. C A, B, C, D. 8/ Gi s bn ni chuyn vi mt ngi cha h nghe ni g v ADN, bng cch no sau y bn c th trnh by s kin ADN l vt liu DT? Dng th nghim Griffth v Avery chng minh vt cht DT ca vi khun l ADN. Dng th nghim ca Hassey v Chase chng minh vt liu DT ca thc khun th l ADN. Chng minh sinh vt nhn chun lng ADN n nh trong TB soma v ln gp 2 ln TB sinh dc. Chng minh vai tr ca ADN qua thnh tu cng ngh DT. C A, B, C, D. 9/ Vt cht DT ca vi khun l: Plasmid. Chui ADN dng vng. Chui ARN dng vng. Gm c A v B. Gm c B v C. 10/ Vt cht DT ca virut l g? Cu tr li no sau y l tha ng nht? Mt phn t ADN trn. Mt phn t ARN trn. Mt phn t axit nuclic trn. Nucleoprotein. Ton b c th ca virut. 11/ Vt cht DT cp phn t ca sinh vt nhn chun l: B NST. H gen. Nucleo protein. Cc phn t axit deoxyribonucleic. Cc phn t axit nucleic. 12/ Thuc th no sau y c th dng pht hin ADN trong TB nghin cu? Lc Metyl. Pironin. Schiff. C A v B. C A v C. 20

www.vietmaths.com 13/ Trt t ng n ca cc cu trc theo th t t n gin (t cu trc cha mt s lng t nht cc loi phn t Protein khc nhau) n cu trc phc tp nht (cu trc cha mt s lng t nht cc loi phn t Protein khc nhau) c a ra trong cc cu tr li sau: A. Tc nhn gy bnh b in, HIV, riboxom ca SV nhn thc, ty th. B. Riboxom ca SV nhn thc, HIV, tc nhn gy bnh b in, ty th. C. Tc nhn gy bnh b in, HIV, ty th, riboxom ca SV nhn thc. D. HIV, tc nhn gy bnh b in, riboxom ca SV nhn thc, ty th. E. Tc nhn gy bnh b in, riboxom ca SV nhn thc, HIV, ty th. 14/ Cho bng t l % baznit cc loi khc nhau: Loi 1 2 3 4 Aenin Guanin Timin 21 29 21 21 29 21 21 29 21 29 29 0 Xitozin 29 21 29 29 Uraxin 0 0 0 21

5 21 29 0 21 29 Hy cho bit vt liu DT ca cc loi trn? CU15: Nu nhng bng chng sinh hc TB v phn t v ngun gc thng nht ca cc loi sinh vt. * Bng chng TB: + Mi c th sng t SV nhn s n nhn chun u c cu trc TB. + TB ca chng u c th thc cu to ging nhau. * Bng chng sinh hc phn t: + VCDT u l ADN, c th thc cu to ging nhau (t 4loi Nu, nguyn tc b sung, s phn cc ngc chiu...). + M DT ph bin chung cho mi sinh gii. + Protein u c cu to t 20 axit amin, c 4 bc cu trc. + Qu trnh truyn t thng tin DT qua cc th h u da vo kh nng t nhn i ca ADN theo nguyn tc b sung, nguyn l bn bo ton v na gin on. + Qu trnh truyn t TTDT thnh tnh trng u thc hin qua c ch sao m v dch m: ADN ARN protein tnh trng CU 16: Trong cc c ch DT cp phn t th nguyn tc v nguyn tc khun mu c th hin nh th no? * Nguyn tc b sung: + Trong c ch t sao: Cc Nu trn mch khun kt hp vi cc Nu t do.... + Trong c ch tng hp ARN: Cc Nu trn mch khun lin kt vi cc ribnucltit.....

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www.vietmaths.com + trong c ch dch m: cc ribonucltit b m sao ca ARNm v b ba i m lin kt... Trong nguyn tc khun mu: + Trong c ch t sao: mi mch n ca ADN m lm khun tng hp mch mi. + Trong c ch tng hp ARN: 1 trong 2 mch n ca ADN mang m gc c dng lm khun tng hp mch ARN. + Trong c ch dch m: mch ARNm lm khun tng hp chui polipeptit. CU17: Khng cn dng bin php sinh hc phn t, ngi ta cng c th lp c bn gen ca VK (xc nh c v tr cc gen trn NST). Hy cho bit l phng php g? V gii thch. Vi bin php ny c th p dng i vi TB nhn thc hay khng? TS? Dng bin php cho VK tip hp vi nhau ta c th lp c bn gen ca VK: + Bi v: Do VCDT ca VK l mt ADN dng vng. Nn khi tip hp ADN s chuyn t TB cho sang TB nhn mt cch t tng gen mt trn phn t ADN . + Trong qu trnh VK tip hp, ta c th lm cho qu trnh tip hp ca VK b ngng li vo nhng thi gian khc nhau. V nguyn tc, nu thi gian tip hp cng di th cng c nhiu gen c chuyn t TB cho sang TB nhn. + V vy, nu thi gian tip hp ngn nht m c mt gen no c chuyn sang TB nhn th gen c xp u bn DT (k hiu gen 1). Thi gian tip hp di hn mt cht s cho c gen 1 ln gen 2 cng sang TB VK nhn. + Tip tc cho tip hp vi thi gian di hn na ta li c c TB nhn vi c 3 gen 1-2-3. C nh vy, ta c th xy dng c ton b bn gen ca VK. + Ta khng th dng phng php ny i vi TB nhn thc, v: -TB nhn thc khng c kh nng tip hp nh TB VK. -VCDT ca TB nhn thc phc tp hn, c b NST ln hn 2 nn khng th phn bit c Gen ca NST no vo TB nhn. CU18: Trong h gen ca ngi, bn cnh cc gen cu trc bnh thng v d nh gen qui nh chui a-trong hmglbin, cn c cc gen c gi l gen gi. gen gi v c bn c trnh t Nu ging vi gen bnh thng nhng li khng bao gii c phin m . Hy cho bit gen gi c hnh thnh trong qu trnh tin ho t gen bnh thng bng cch no? + u tin trao i cho khng cn dn n hin tng lp gen, sau B xy ra lm mt hoc hng on promot khin cho ARNpolimraza khng th hin phin m gen ny c mc du trnh t m ho ca gen vn bnh thng. + Cng c th trong qu trnh trao i cho khng cn, gen c lp b mt on prmt nn thnh gen gi. CU19: ARNm c phin m in vitro t mt phn t ADN si kp, phn s sau c tch thnh 2 si n. Ngi ta phn tch t l baz ca mi si ADN v so snh vi t l ARNm. Trn c s ca cc s liu cho trong bng, Hy xc nh si no ca phn t ADN si kp c dng lm khun tng hp ARNm. A T hoc U G X ADN-1 27,0 32,5 18,5 22,0 22

www.vietmaths.com ADN-2 32,7 26,8 22,1 ADN-3 28,0 33,0 17,0 ADN-4 25,0 33,0 17,0 ARNm 27,0 33,0 17,0 CU20: ADN no di y l c cht cho ADNpolimraza? 1 2 5'3' 5' 3' Primer 3' 5' 3'

18,4 21,0 23,0 23,03' 5'

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5' 5' Primer 3'

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CU21: Hy cho X l lng ADN trong nhn ca mt giao t ca c th lng bi. Hy in vo ch trng lng ADN trong nhn cc giai on khc nhau ca chu k TB ca sinh vt ny.P G2 S G1 T T = K cui (Telophase). A = K sau (Anaphase). M = K gia (Metaphase). P = K u (Prophase).

Khi lng ADN trong TB cc giai on sau y ca chu k TB: 1. Gia giai on S: 2X 2. G1: 2X 3. G2:4X 4. K u:4X 5. K gia: 4X 6. K sau: 4X CU22: Cc qu trnh t 1 - 6 xy ra trong mt TB nhn chun theo trnh t no? Chuyn nhm peptidyl. Gn riboxom vo ARN. Gn ARNpolimeraza vo ADN. Ct cc intron ra khi ARNm. Sao m. Chui polipeptit cun li. Hy sp xp cc trnh t trn theo c ch DT. 3, 5, 4, 2, 1, 6. CU23: Cht nhim sc ca TB ngi cha 1,08mg histn v 0,7mg protein khng phi histn trn 1mg ADN. Gi s rng mi mol ca 1 gen trung bnh cha 106g ADN v khi lng phn t trung bnh ca histn l 12000dalton, ca cc protein khng histn ca cht nhim sc l 17000 dalton. Bao nhiu phn t protein NST tham gia to phc hp trong 1 gen trung bnh? Nu 1TB ngi trung bnh cha 1013 dalton ADN, th c bao nhiu phn t protein tham gia to phc h trong ? Theo mt l thuyt gii thch s iu ho biu hin gen SV nhn thc, mt s protein NST xc nh ng vai tr l cht hot ho, lm hot ng nhiu nhm gen ln. gi s mt cht hot ho nh vy kch hot s biu hin ca 1000 gen. Nu mi 23

www.vietmaths.com gen cn 1phn t cht hot ho v cc TB l lng bi th bao nhiu % protein NST ng vai tr hot ho. 1. S phn t protein histn: 90. S phn t protein khng phi histon: 41. 2. 1,31 x 109 . 3. 0,00015%. CU24: im mu cht no trong c ch t nhn i ca ADN m bo cho phn t ADN con c trnh t nucltit ging phn t ADN m? + Nguyn tc "gi li mt mch" ca ADN m trong ADN con. + Nguyn tc b sung. CU25: VS trong 2 mch polinucltit mi c tng hp th mt mch c hnh thnh lin tc cn mch kia c hnh thnh tng on? +Trn mch mi tng hp, cc Nu t do c lp theo chiu 5' 3' , ngc vi chiu ca mch ADN m. + Enzim ADN-polimraza lm vic t u 5'. CU26: Di y l trnh t cc Nu trong mch mang m gc ca mt on gen m ho cu trc ca enzim hirgenaza ngi v cc loi vn ngi: 1 2 3 4 5 6 Ngi: - XGX-TGT-TGG-GTT-TGT-TGGTinh tinh: - XGT-TGT-TGG-GTT-TGT-TGGGrila: - XGT-TGT-TGG-GTT-TGT-TATi i: - TGT-TGG-TGG-GTX-TGT-GATDa vo bng m DT, hy xc nh trnh t cc axit amin trong on polipeptit tng ng mi trng hp trn. Cc kt qu cu 1 cho php rt ra nhng nhn xt g v mi quan h gia s bin i cc Nu trong codon (b ba m ho) vi s bin i axit amin trn polipeptit? Nhng dn liu trn cho php nhn nh nh th no v mc quan h thn thuc gia cc loi vn ngi vi ngi? 1 2 3 4 5 6 Ngi: - XGX-TGT-TGG-GTT-TGT-TGGAla - Thr - Thr - Gln - Thr - Thr Tinh tinh: - XGT-TGT-TGG-GTT-TGT-TGGAla - Thr - Thr - Gln - Thr - Thr Grila: - XGT-TGT-TGG-GTT-TGT-TATAla - Thr - Thr - Gln - Thr - Il i i: - TGT-TGG-TGG-GTX-TGT-GATThr - Thr - Thr - Gln - Thr - L 2. Quan h gia bin i trong codon dn n bin i trong polipeptit: Bin i cc Nu th 3 trong codon thng thng khng gy bin i trong dy axit amin (XGX - XGT). Bin i Nu th 2 hay th nht trong codon dn ti bin i trong dy axit amin (TAT - GAT).

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www.vietmaths.com Khng phi bt c bin i no trong cc Nu ca gen cng gy bin i tng ng trong polipeptit, mi axit amin c th c m ho bi nhiu codon (M DT c tnh thoi ho). Mc quan h h hng gia cc loi Vn ngi v ngi: Tinh tinh c quan h gn vi ngi: trnh t Nu trong gen ging ht trnh t ngi. t bin G --> A codon 1 cng khng lm thay i axit amin. Sau tinh tinh l Grila ri n i i. Mc sai khc nhiu hay t trong cc Nu ca ADN phn nh quan h h hng gn hay xa. CU27: Nghin cu s khng thuc ca t cu vng Staphylococus aureus, ngi ta tnh rng Vit Nam c n 70% s t cu vng mi phn lp c kh nng khng penicilin gc. S khng thuc ny thng c ngun gc t plasmid. Vy plasmid l g? S c mt ca plasmid trong vi khun cho php n sinh tng hp mt loi phn t mi. l phn t g? Hot ng ca phn t ny nh th no? Ngi ta lm mt khng sinh i vi chng thun Staphylococus aureus c phn lp t mt ngi bnh cha bng khng sinh penicilin. Chng vi khun ny xut hin s khng ng thi c i vi penicilin v tetracilin (bit rng lc u khi cha bnh, cc t cu vng l nhng chng mn cm vi c loi khng sinh trn). + C th gii thch hin tng trn nh th no? + Ngi ta c th s dng phng php iu tr no trnh hin tng trn? Plasmid: L ADN nm ngoi NST, kch thc ch bng khong 1/100 th nhim sc, c th nhn ln c lp vi s nhn NST. l Penicillnase (-lactamase): mt enzim phn gii penicilin bng cch b gy vng -lactamase. Cc plasmid thng gip VK khng vi nhiu khng sinh cng loi, bi v s c mt ca cc gen m ho nhiu enzim ph hu cc khng sinh ny nm k vi nhau. Ngi ta c th s dng phng php iu tr phi hp nhiu loi khng sinh. CU28: Bng hnh v hy phn bit m-ARN, t-ARN v r-ARN. Hy cho bit cc thu trn phn t t-ARN c chc nng g? T c im v cu trc ca cc loi ARN th d on v thi gian tn ti ca mi loi trong TB, gii thch ti sao? Hnh v 8.11 trang 68 sinh hc tp 1- Phillips-Chlton. Chc nng: Mt thu mang b ba i m (khp vi b ba m sao trn m -ARN), mt thu lin kt vi enzim, cn mt thu lin kt vi ribxom. 2. Thi gian tn ti mi loi ARN trong TB ph thuc vo bn vng ca phn t do cc lin kt hyr to ra. Phn t m-ARN khng c lin kt hyr nn d b enzim trong TB phn hu, c thi gian tn ti ngn nht. Phn t r-ARN c ti 70% l cc lin kt hyr nn c thi gian tn ti lu nht.

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www.vietmaths.com CU29: Khi nghin cu v kch thc h gen (hm lng ADN tnh theo s lng cp nuclotit-bp ca mt TB n bi) mt lot cc loi sinh vt khc nhau trn bc thang tin ho ngi ta thu c s liu sau: Nhm sinh vt Kch thc h gen (bp) Mycoplasma. 1,0 x 106 E.Coli (Vi khun). 4,2 x 106 C.elegans (Giun trn) 8,0 x 107 D.melanogaster (Cn trng) 1,4 x 108 X. laevis (Lng c) 3,1 x 109 G.domesticus (chim) 1,2 x 109 H.sapiens (ng vt co v) 3,3 x 109 Hy so snh kch thc h gen cc loi trn, t c th rt ra nhn xt g? Nhn xt: + SV n bo c kch thc h gen nh hn sinh vt a bo. + VKXS c kch thc h gen nh hn VCXS. + Xt v mc phc tp v t chc v cu trc c th th kch thc h gen cha phn nh v tr ca loi trong thang tin ho (chim tin ho hn lng c nhng kch thc h gen nh hn). + Kch thc h gen cc loi khc nhau th khng ging nhau. CU30: Nhim sc th v ADN ca ngi v tinh tinh c g ging v khc nhau? nhng dn liu ny gp phn cng c kt lun g v mi quan h ngun gc gia ngi vi vn ngi? + NST ngi c 2n = 46, Tinh tinh c 2n = 48; NST s 2 ca ngi l kt qu dnh nhau ca 2 NST tinh tinh. + ADN ca ngi v tinh tinh ging nhau 92% s cp nu. + Nhng dn liu trn gp phn cng c kt lun ngi c quan h thn thuc vi vn ngi, c bit rt gn gi vi tinh tinh. CU31: Hy gii thch TS ADN cc SV nhn thc thng bn vng hn nhiu so vi tt c cc loi ARN. Nhit m phn t ADN mch kp b tch thnh 2 si n gi l nhit "nng chy" . Hy cho bit cc on ADN c cu trc nh th no th c nhit "nng chy" cao v ngc li. TS ADN nhn TB c kch thc rt ln nhng vn xp gn trong nhn? s sp xp nh th no? Vic xp gn c nh hng n kh nng tip xc ca ADN vi protein khng? 1. + ADN c cu to t 2 mch n cn ARN c cu to t mt mch n. Cu trc xon ADN phc tp hn. + ADN thng lin kt vi protein nn c bo v tt hn. + ADN c bo qun trong nhn, khng c enzim phn hu chng, trong khi ARN thng tn ti ngoi nhn, nn c nhiu enzim phn hu axit nuclic. 2.Nhng on ADN c nhit :nng chy" cao l nhng on c cha nhiu loi G-X v s lng lin kt hyr nhiu hn, ngc li, cc on ADN c nhiu cp A-T , t G-X th c nhit nng chy thp hn do c t lin kt hyr hn. 3. S sp xp ADN nhn TB: 26

www.vietmaths.com + ADN TB c nhn c kch thc rt ln nhng vn c xp gn trong nhn l do cu trc xon phc tp ca ADN. Cc phn t ADN c nn cht trong th tch rt hn ch ca nhn. Vic nn cht thc hin nhiu mc , thp nht l t nucleosome, solenoit ti si nhim sc. + Cc protein c vai tr cu trc nn cht ADN trong nhn nh cc histn lin kt vi phn t ADN nh lin kt ion gia cc nhnh bn mang in tch m mang in tch m ca histn vi cc nhm photphat mang in tch dng ca ADN. + Vic xp gn ADN trong nhn khng nh hng ti kh nng tip xc ca ADN vi protein v ADN qun quanh li cu to t nhiu histn nn d c nn li phn ln b mt ca ADN vn c kh nng tip xc vi protein khc (VD: ADNpolimeraza trong sao chp, ARN-polimeraza trong s phin m hay cc protein iu ho hot ngc ca gen). CU32: Phn tch hm lng ADN trong TB theo thi gian qua qu trnh gim phn ngi ta thu c kt qu sau: Thi gian (gi) 0 2 3 4 5 6 7 8 8,5 9 9,5 10 12 Hm lng ADN 2c 2c 2c 3c 4c 4c 4c 4c 2c 2c c c c (c) (c l hm lng ADN trong TB n bi). + V th din bin hm lng ADN trong TB. Gii thch.Hm lng ADN

0

2

4

6

8

10 Thi gian

+ Trong gi th 4 din ra qu trnh t nhn i ca cc phn t ADN lm cho hm lng ADN trong TB tng gp i, t 2c ln 4c. + T gi th 8 din ra s phn chia gim nhim ca gim phn I. Hm lng ADN trong TB gim mt na, t 4c xung 2c. + T gi th 9 din ra s phn chia nguyn nhim ca gim phn II. Cc NST kp tch ra, mi TB con nhn 1 NST n trong cp, do hm lng ADN gim t 2c xung c. CU33: Hnh v di y cho thy cc loi lin kt trong phn t ADN:-

O

P1

2

O CH23 4

CH2 O-

O

P

O

-

O

Hy cho bit cc v tr: 1, 2, 3, 4 l cc loi lin kt g. im khc nhau v ngha ca lin kt 1 v 4 l g?

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www.vietmaths.com Lin kt este photphat, 2. lin kt cng ho tr, 3. Lin kt glucozit, 4. Lin kt hyr. Khc nhau: 1 c nng lng lin kt ln, gc lin kt c nh, c vai tr to mch polinucltit theo nguyn tc a phn. 4 c nng lng lin kt nh (khong 5 kcal), gc lin kt khng c nh m tu thuc vo dng (A,B,Z, T...), c vai tr to cu trc khng gian, m bo cho ADN va bn vng va linh ng. CU34: Mt nh bc hc lm th nghim nh sau: Nui cy E.coli trn mi trng c timin nh du bng Tritium. Sau cc thi gian nui cy khc nhau, em li gii t bo vi khun bng mt phc h gm enzim phn gii cng mt loi thuc ty, ADN c gii phng ra. em ADN t ln phin knh mng. Phin knh c ch kh v sau c ph ln nh hn dch thuc nh. Hai thng sau bc lp nh chp ra, em quan. 1.Theo em c th quan st thy g? 2.T th nghim ny ta c th rt ra kt lun g? 1. Quan st thy: - y l th nghim ca Cairn. - Do timin trn ln vo ADN lm cho ADN c tnh cht phng x. - Sau cc thi gian nui cy, li gii th ADN c gii phng ra. Cc bc tip theo nhm quan st ADN s thy nhng si c nht c hnh vng trn, chu vi di 1400micromet. y chnh l ADN ca E.coli c hnh thnh bi mt chui plinucltit kp, trong 1 si mi c hnh thnh (c Timin nh du) trn khun si c. - Ngoi ra c th quan st thy c nhng si b gy. 2. Kt lun: ADN ca vi khun E.coli t nhn i theo nguyn tc bn bo ton, nguyn tc b sung, nguyn tc na gin on.

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