Cẩm nang tự ôn và luyện thi sinh học

Ldl NOI DAU DC- CO tlic dal kcl qua tot trong cac ki tlii Tot nghicp THPT, tuyen sinli vao cac trUflng Cao dang. Dai iioc. hoc sinh can nam dUOc chuan kicn ihiYc, kl nang ci'ia chUOng trinh THPT. Cuthela: 1 - Fhai nh('(, nam vilng, hicu ro cac kicn thtfc c(J ban trong chirring trinh, sacii giao khoa mon Sinh hoc cap THPT, chu yeu la Idp 12. 2 - Phai bie't \&n dung cac kicn thifc da hoc de tra cac cau hoi, gitii bai lap, liim thiTc hanh va iJng dung vao thifc tien, dtli song. 3 - Phai ren luyC-n cac lhao tac, tu' duy: Plian tich diftfc cac sU kien, dff kien thCfa, thie'u hoac dii de giai quyet diMc cac van dc cii the. Xac dinh diWc moi quan he giiTa cac bo phan trong toan the; cu the hoa dmic nhiTng van de trifu tifdng; nhan biet vii hicu difrtc cac bo phan cau thanh; ket hOp du'dc nhicu ycu to thanh mot tdng the hoan chi'nh; khai quat hoa dUOc nhiTng van dc rieng Ic, cu the. Suy luan tiT nhCtng kie'n thiVc da c6 de md rong kicn thiJc, phat trien nang liTc nhan thiJc. Hicn nay, de thi tot nghiep THPT, tuyen sinh vao cac trufcing Cao dang, Dai hoc mon Sinh hoc la hinh thifc thi trac nghicm. Do la hinh thiJc kiem tra, ma trong do dc kiem Ira thirClng gom nhicu cau hoi. Moi cau ncu ra mot van de ciing vdi nhifng thong tin can thic't, sao cho thi sinh chi phai tra Idi van tat doi vdi iCmg cau hoi. De lam to't hinh thiVc thi trac nghiem, ngoai vice on tap c6 ke' hoach, chuan hi noi dung kl thi hoc sinh can phai lam qucn vdi hinh thiJc thi nay. Tuy nhicn, khong can phai lam that nhicu, chi can liim quen vdi mot so cau hoi theo tifng npi dung, ti^ng phan hoc nhif: Cd chc'di truyen vii bic'n di, Di truyen hoc qudn the, Di Iruyen hoc ngifdi, dc nam du'dc each ra de thi, kT thuat liim biii thi trii'c nghicm. Quan trong nhii't lit phai trang bi kien thifc diiy du, he thong, phai ren luyen tot ctic thao tac tu" duy ihi nidi cd the dat kc't qua tol trong cac ki thi. Vc ciiu hoi cd the chia thanh 2 loai; Ciiu hoi "thuoc bai" vii ciiu hoi "hieu bai". Trong cuon sach nay chiing toi khong de cap den cac cau hoi "thupc bai", khong phai vi chiing khong quan trong, ma vi chiing dii difdc trinh bay day du, ro riing d SGK. Chiing toi chi de cap cau hoi "hieu biii" tiJc lii nhiTng cau hoi gitip hoc phan tich, so sanh, tdng hdp, suy luan dc cd the hicu bai mot each sau sac. TCf do mdi dc thupc bai mdi vii van dung diidc bai hpc. VI du: Chiing toi khong hoi: Phien ma la gi? Trinh bay dien bien va kc't qua ciia qua trinh phien mil nhu'd SGK ma chiing chi dc ra cac ciiu hoi biipc hpc sinh phai siV dung cac thao tac tu" duy dc tim hieu cac kicn thuTc cua biii phien mil nhu": Trong qua trinh phien nm cd su" tham gia cua cac yeu to nilo? Vai tro ciia moi ycu to do (khuon, nguycn lieu, enzim xiic tiic) phien mil bat dau va chii'm diJt d vi tri niio tren khuon, chicu cua mach khuon, chieu tdng hdp va nguycn tac tdng hdp. Hicn tifdng xay ra khi kc't thiic phien ma? Qua dd cho bic'l cd che'phien ma lii gi? mARN difdc tao thiinh sau phien ma d te bao nhiin sd va te bao nhan thiTc khac nhau d diem nao? Ve bai tiip cung cd the chia thanh 2 loai: Biii tap tif luan vii bai tap trac nghicm. Chiing toi chu y nhicu hdn ddi vdi biii tap tif luan. Vi tif luan toi se trac nghicm tot va qua tif luan cd the ren luyen tif duy tot hdn, danh gia du'dc diiy du hdn ve ket quii hpc tap cua hpc sinh. Kinh mong cac thay giao, cac bac phu huynh vii cac em hpc sinh ddng gdp them y kien dc cd the bd sung, hoiin thien diin cudn sach niiy. Tac gid Cty TNHH MTV DVVH Khang Vigt Chu-orng 1. CO cut DI TRUYjfeN A. Cd CHE DI TRUYEN 6 CAP DO PHAN TLf I. TOM TAT NOI DUNG Trifdc ticn, hpc sinh can nhd rdi he tho'ng lai toan bo cac kie'n ihtJc da du'dc hpc trong chiTimg trinh THPT vc CO sd VAT CHAT va Cd CHE DI TRUYEN d CAP DO PHAN TO. Cti the nhu' sau: 1. Gen la cd sd vat chat di truyen (If cap do phan tijT Dt) la mot doan axil nucleic (ADN hotic ARN) difdc can tao lii4 loai nucleotit A, T, G, X. Co mpl cht'fc nang di truyen nhii't dinh nhif ma hoa chuoi polipeptit, hoac phiin tif ARN, dieu hoa hoal dpng cua gen, ; ,, 2. Gen cau true c6 3 vunj» trinh t\i nucleotit Viing dieu hoa nam d diiu 3' ciia mach mii go'c mang tin hieu khdi dpng vii kiem soat phien ma. vung mii hoa mang thong tin mix hoa cac axil amin, c6 the lien liic (d te bao nhan .sd) hoac khong hen liic, tti'c lii xen ke cac doan ma hoa axil amin (cxt)n) lit ciic doan khong mii hoa axil amin (intron) (d te' bilo nhan ihifc); viing ket ihuc nam d dau 5' ciia mach goc mang tin hieu ke'l thiic phien ma. 3. Gen chifa thon^ tin di truyen diftJi hinh thufc ma hoa Ma di truyen lii ma bp ba, life la 3 nucleotit dtJng hen nhau ma hoa mpl axil amin. Vi c6 4 nucleotit nen c6 4^ =64 bp ba ma hoa (Triplet) tifdng I'fng vdi 64 codon tren mARN. Trong do co 1 bp md dau lii AUG ma hoa axil amin md dau (Melionin hay foocmin Metionin) 60 bp ba ma hoa cac axit amin khac, va ba bp ba ket thiic lii UAA, UAG, UGA khong ma hoa axil amin nao. Mil di truyen c6 dac diem: Khong go'i len nhau, c6 linh phd bic'n (chung cho mpi loai) linh dac hieu (mot bp ba chi ma hoa 1 axit amin) va linh Ihoai hoa (c6 the nhicu bp ba ciing mii hoa mpl axil amin). Mai di Iruyen trong ADN du'dc phien ma sang ARN. ' ' ^ 4. Phien ma Sif Iruyen thong tin di Iruyen phan Ivi ADN mach kep .sang phan tijf ARN mach ddn (mARN, lARN, rARN) la qua trinh phien ma (hay lii qua trinh long hdp ARN). O te bao nhan ihifc, phien ma dien ra trong nhiin te biio, 0 ki Irung gian giifa 2 Ian phan biio, liic NST d dang sdi manh. Qua trinh phien ma hinh thiinh mARN dien bien nhU sau: Tru'dc lien, ARN polimeraza nhan biet trinh lif cac nucleotit dac biet tren ADN (lai viing dieu hoa) de bam vao vung dieu hoa, lam gen thao xoSn dc Ip ra mach ma gdc cd chicu 3' -> 5'. ARN polimeraza trifdl tren mach goc, xuc lac long hdp mARN Ca'm nang \\J 6n va luygn thi Sinh hgc - Phung Duy D6ng Iheo nguycn lac bo sung (A - U, G - X). Khi gap tin hieu ke'l Ihi'ic (d vung kc't thuc) till dtrng phicn ma, ARN du'Oc giai phong. Viing nao phien ma xong thi hai mach ddn cua gen dong xoan ngay. O te bao nhan scf mARN dtfrtc diing de dich ma ngay con d te' bao nhiin Ihifc thi dirdc cat bo intron noi cac cxon lai thanh mARN iriidng lhanh, m(1i diing de djch ma. 5. Djch ma La giai doan ke tiep sau phien ma, truyen thong tin di truyen ttf m ARN (Ban ma sao) sang chuoi polipeptit. Tij" do quy dinh cac tinh Irang. Qua tnnh dich md fidin 2 iiiai doan: a) Hoat hoa axit amin Trong to bao chat, nhd cac enzim dac tru'ng va nang lu'dng ATP, mdi axit amin du'dc hoat hoa va gan vdi lARN lu'dng iJug lao nen phi'fc he aa - lARN. b) Toiig lufp chuoi polipeptit Moi riboxom gdm 2 lieu phan, binh Ihu'dng nam Uich nhau, khi c6 mat mARN chung lien ke'l v('Ji mARN lai codon m 5 dau. Tren riboxom c6 2 vi Iri la P (peplil) va A (amin). Moi vi Iri tiTdng tfng vdti mot bo ba. Nhd do riboxom giiJ vai tro nhu" mot khung del giiJa mARN vdi aa.lARN va giffa codon - anticodon. Nhd CO bo ba doi ma (anticodon) ma aa - lARN c6 the nhan bie't codon lu'dng iJng do mang axit amin den diing vi tri va khdp bd sung vdi codon lu'dng iJng tren mARN. Dau tien lARN mang axit amin met dau la Metionin (d te' bao nhan sd la foocmin Metionin) den dung vi tri cua codon md dau. Tiep theo lARN mang axil amin thu' nhat (aai - tARN) den vi iri codon thiJ nhat. Lien ke'l peplil giffa Metionin va axil ihii' nhat du'dc lao lhanh (nhd xiic lac ciia enzim), lARN rdi khoi ribdxdm. Sau do riboxom bat dau chuyen dich tijfng na'c, mdi nac u'ng vdi mot codon va qua trinh dich ma lai xay ra lu'dng liT. Khi gap codon ke'l thuc thi diifng phien ma. Riboxom tach khdi mARN, chudi polipeptit du'dc giai phong, axit amin md dau du'dc cat bd, chudi polipeptit tiep tuc hinh lhanh cac cii'u true bac cao hdn, Ird lhanh protein hoan chinh. Tren mdi phan tu" mARN thu'dng c6 mot so'ribdxdm hoiit ddng (poHribdxdm). Nhtf vay, mdi phan tii' mARN cd the long hdp liT mdt de'n nhieu chudi polipeptit cung loai. Sau khi tdng hdp, mARN du'dc enzim phan giai, con ribdxdm du'dc sij" dung qua vai the'he te'bao. 6. Dieu hoa boat dong cua gen La dieu hoa lu'dng san pham cua gen du'dc lao ra. 6 sinh vat phan sd, dieu hoa hoat dong cua gen chu ye'u dien ra d giai doan phien ma trong cac opcron. 6 sinh vat nhan thifc, dieu hoa hoat dong cua gen dien ra qua nhieu giai doan nhU: NST thao xoan, dieu hoa phien ma va sau phien ma, dieu hoa dich ma va sau dich ma. Cty TNHH MTV DVVH Khang Vigt Dieu hoa boat dong ciia gen lai cac operon dien ra nhu' sau: Khi moi tru'dng noi bao khong c6 chat cam u'ng, gen dieu hoa tdng hdp chat ifc che', gan vao viing van hanh (O) ngiin can phien ma cua nhom gen ca'u true (operon d trang thai vie che). Khi moi tru'dng ndi bao c6 chat cam u'ng thi chat cam u'ng lien ke'l vdi chat (ic che' lam cho no khdng the lien ke'l difdc vdi viing van hiinh, nhom gen ca'u true chuyen sang Irang thai hoat ddng, qua trinh phien ma, dich ma xay ra. 7. Sil" bieu hien kieu hinh ciia gen Thdng tin di truyen chi'fa trong gen du'dc bic'u hien lhanh tinh trang cua cd the thong qua c(< che phien ma tif gen sang mARN rdi dich ma tCr mARN sang protein va lif protein bieu hien lhanh tinh trang. Mdi te bao deu chii'a day dii loan bd cac gen quy dinh ca'u triic tat ca cac loai protein cua cd the. Nhifng trong qua trinh phat trien ca the, tuy tifng te'bao trong liYng loai mo, tijy lifng giai doan phat trien ma chi mdt so' gen trong do boat ddng, life la te'bao chi long hdp loai prdtcin can ihic't vao liic can thiet thdng qua cd che dieu hoa hoat ddng gen. Sif bieu hien kieu hinh ciia gen con chiu sir tifdng lac giiTa cac gen, lu'dng tac giu'a kieu gen vdi mdi tru'dng va con phu thudc vao vi tri ciia gen nam tren NST thu'dng hay NST gidi tinh, nam trong nhan hay ngoiii nhan. vao sir phan li ciia gen (phan li ddc lap, phan li cung nhau). vao sir lien ke'l cua cac gen (lien ke'l hoan loan, lien ket khdng hoan loan). , ,. '. Tinh cha't ciia gen ^ V) CO can tao da phan nen: - Gen cd tinh da dang va tinh dac thii, do lhanh phan, so' lu'dng, trat lir xap xe'p ciic bo ba trong gen quy dinh. - Gen cd kha nang dot bien va di truyen cac ddl bie'n cho the' he sau. - Gen cd khii nang tai ban (qua sir nhan ddi ciia ADN) cd kha nang phan li va id hdp (qua sir phan li va id hdp ciia NST) qua do truyen thdng tin di truyen cho cac the he sau. 9. Qua trinh nhan ddi ciia ADN Dien ra ngay tru'dc khi te'bao bu'dc vao giai doan phan chia + O sinh vat nhan sd: Nhd enzim thao xoan (Helicaza), hai mach dcfn ciia phan li? ADN dirdc tach ra tao lhanh chac chCr Y (ddn vi lai biin). Mdi mach ciia ADN deu dirdc lam khudn de long hdp mach ADN mdi. Vi mach 3' 5' phat trien ihuan vdi chieu thao xoan (T 5') nen mach mdi tdng hdp tren mach khudn 3' 5' du'dc tdng hdp lien tuc theo chieu 5' 3' tao lhanh phan luT ADN con cd 2 mach chieu ngirdc nhau. Con mach mdi long hdp tren mach khudn 5' —)• 3' phai tdng hdp tirng doan ngan (doan Okazaki) (vi ngu'dc vdi chieu phat trien ciia chac Y). Sau dm nang tij fin va luyjn thi Sinh hpc - Phung Duy Odng do ciic doan nay diroc no'i lai vcfi nhau (nhcJ ezim no'i ligaza) mdi tao thanh phan tu' ADN con hoan chinh. Trong qua trinh nhan doi ADN c6 nhieu cnzim lham gia, trong do enzim chinh la ADN polimeraza, lam nhicm vu xiic tac siTkien ket gii?a cac nucleotit tiT do vdi cac nucleotit ciia mach khuoii iheo nguyen tiic bd sung (A - T, G - X). Cudi ciing tuf 1 phan lif ADN sau nhan doi tao thanh 2 phan tur ADN gio'ng het ADN ban dau. Trong moi phan tuf ADN du^dc tao thanh thi mot mach la mdi dm^c long help con mach kia la cua ADN ban dau (nguycn tac ban bao ton). Nhu'vay, qua trinh nhan doi ADN da dien ra Ihco nguyen tac bd sung va ban bao ton vdi sir xiic lac cua cac enzim dac tru'ng, nhd do da tao ra 2 ADN con gidng het ADN me, bao dam cho siTdi truyen cac gen qua cac he Ic bao mot each chinh xac. + O sinh vat nhan thi/c: ' Vi CO nhieu nhan lu" ADN kich thu'dc Idn nen su" nhan doi ADN x;iy ra lai nhieu diem trong mdi phan lit ADN tao ra nhieu ddn vj lai ban (nhan doi) va du'dc nhan doi ddng thdi. II. CAU HOI TU LUAN Ve cdu hoi tu luan chuiii^ toi chia thanh 2 lout: 1. Cau hoi phan tich bai hpc thanh tiTng phan, tiTng y mot each he thong dc hoc, de hieu va de nhd (cau 10, 11,12, 13, 14, 15,16). 2. Cau hoi ren luyen cac thao tac tu'duy de giiip cac em biet phat trien va van dung kien thitc (cac cau con lai 1, 2, 3, 17 ^ 38). Cau 1: Gen la gi? Co cac each trii Idi sau: A. Gen la mot doan ciia phan tii' ADN, mang thong tin ma hda mot chuoi polipeptit hay mpl phan lu" ARN. B. Gen la mot doan cua phan tu* ADN mang thong tin ma hda cho mpl san pham Xiic dinh. C. Theo nghia rpng, gen la mpl doan phan ti'r axil nucleic mang thong tin quy dinh cau true ciia mpl chudi polipeptit, lARN, mARN hoae lam nhicm vu dieu hda, khdi ddng D. Gen la vat chat di truyen d cap dp phan tij". E. Gen la mot doan phan tii' axil nucleic, du'dc cau tao tij" cac ddn phan nucleotit (A, T, G, X). G. Gen la mot doan ciia phan tu" ADN cd chtfc nang di truyen nhat dinh. Hay danh gia (dung luyct doi, dung tUdng doi, sai, Ihieu chinh xac, chifa dii, ) va du"a ra y kien ciia minh. Dung tu-png doi la dung trong mot dieu kien nhat dinh. Vi du: Nu'dc sdi d 1(X)"C chi diing tu'dng doi (dung vdi dieu kien nhiet dp va ap suat binh thirdng). Cty TMHH lyJTV DWH Khang Vi^t HU('/ng ddn Ta't cii cac cau trcn chi diing trong nhiirng dieu kien nha't dinh. Vi gen cd cau true mach ddn (mpl sd chiing virut) mach thang, mach vdng Khdng phai gen nao Cling mang Ihdng tin ma hda mot san pham xac dinh, khdng phai mpi gen deu cd chifc nang di truyen, cd gen gay chet, gen bat hoal, - Cd the Ira Idi nhu" sau: Gen la cd sd vat cha't di truyen d cap dp phan tii". Dd la mot doan axil nucleic cd mpl cMc nang di truyen nha't dinh, hoac bift hoal, gay chet, Cau 2: Cau tao, chiJc nang, tinh chat ciia gen? Giai ihich vi sao gen cd nhffng tinh chaldd. HUoiigddit - Gen cd nhieu loai, mdi loai cd cau tao va cMc nang khac nhau. SGK chi trinh bay cau true chung ciia gen cau Iriic. - Gen cd linh da dang, tinh dac thii (do cd cau tao da phan), cd kha nang tai biin (VI gen la mot doan ciia ADN, nen khi ADN lai ban gen cijng du'dc lai ban) cd kha niing phan li vii id hdp (vi gen chiJa trong nhiem sac the, ti the, lap the nen khi chiing phan li va to hPp se dan den sifphan li va id hdp cua gen). Gen cd khii nang dpthien do sifket cap khdng dung trong nhan doi hoac do tac nhan dot bien. Cau 3: Qua trinh nhan doi ciia ADN xiiy ra li'ic nao? Cd siT lham gia ciia cac yeu id' nao? Vai trd ciia cac yeu id' dd? Qua trinh nhan doi ciia ADN dien ra theo nguyen tac nao? Cd y nghia gi? Chieu thao xoan, chieu long hdp? HUdiig ddn - Qua Irmh nhan doi ciia ADN xiiy ra d ki trung gian ngay tru'dc khi le bao bu'dc vao giai doan phan chia te bao. - Ccic yen id lham gia: 2 mach ddn ciia gen (liim khudn); cac nucleotit tif do (nguyen lieu de idng hPp mach mdi); enzim xiic lac: hclicaza (lach 2 mach ddn); ADN polimeraza (xiic lac si; lien ket giffa cac nucleotit tiT do vdi cac nucleotit ciia mach khudn); ligaza (ndi Ccic doan dkazaki vdi nhau). - Nguyen tac: Nguyen lac bd sung (A - T, G - X) vii nguyen lac ban biio Ion (giu" lai mot mach). - Chieu lhao xoan: Ngu'dc vdi chieu xoan ciia phan lu" ADN (lir phiii sang trai). - Chieu tdng hdp: Ngu'dc vdi chieu ciia mdi mach khudn. - Y ngliTa: Tao dieu kien cho nhidm sac the nhan doi, Ic' bao phan chia va suf truyen 1 each chinh xac cac gen qua cac the'he ADN, the'he tc bao. Cau 4: Hay giai thich vi sao tren true chi? Y chi cd mot mach ciia phan tuf ciia ADN du'dc tdng hdp lien tuc, mach con lai difdc tdng hdp mot each gian doan. Co mot sd each gicii Ihich nhUsau: a) Vi ADN polimeraza chi long hdp mach mdi theo chieu 3' —> 3'. ' h) VI ADN polimeraza chi cd the bd sung nucleotit vao nhdm 3' - OH. • • , • • 7 c) Vi ADN polimcraza khdi dau can c6 nhom 3'- OH d dau mach khuon. Thco cm tra Uli nhifcac each trcn c(3 dung khong? VI sao? Hay giai thich theo suy nghi cua cm. HU(htg dan - Ne'u VI ADN polimcraza chi long hdp mach mdi theo chieu 5' —> 3' ihi se khong dung khi thao xoan liTdau 5' ciia mach ma goc. - Ne'u VI ADN polimcraza chi c6 the bo sung nucleotit vao nhom 3' - OH thi khong giiii thich difdc gi vl mach niio cung c6 nhom 3' - OH. - Neu VI ADN polimcraza khdi dau can c6 nhom 3' - OH nhu'ng thao xoan bat dau ttjf dau 5' ciia mach ma goc thi sao? Co dung nvtii khong? Do do nguyen nhan chii yeu la each thao xoan. Co the gicii thich nf^uyen nhcin cua sUtdn^ hcfp ngdt qudng nhusau: Do thao xoan bat d;ui tu" dau 3' ciia mach ma goc vii phia ngu'cfc vdi chieu xoan ciia phan tii" ADN nen mach ADN mdi, long hcfp til' khuon la mach ma goc (3' -> 5') se phat trien thuan vdi chieu phat trien ciia chac chu" Y nen du'c.^c long help lien luc. con mach ADN mc'Ji, long hcfp tu" khuon la mach bo sung v6i mach ma goc (5'^ 3") phiii du'cfc long hdp tifng doan ngSn ngi/cfc vdi chieu phat trien cua chac chi? Y. Nhu" vay mc'-fi lao thanh phan tu" ADN mcfi co 2 mach ngu'dc chieu nhau. Gia sit thao xoan bat dau cuoi mach ma goc ihi ke't qua se ngu'cfc lai, nghla la mach ADN dMc long hdp lit mach ma goc 3' -> 5' phai bi long hdp ngat quang. Do do nguyen nhan la do each thao xoitn va dac diem cau lao cua phan lii' ADN la CO 2 mach ngu'dc chieu nhau. Cau 5: VI sao ma di Iruyen la ma bo ba. Ne'u trong phan tii' ADN c(3 cho 2 hoac 3 loai nucleotit thi c6 the mii hoa du'dc bao nhieu loai axit amin? Hid'fng dan Vi CO 4 loai nucleotit (A, T, G, X) neu ma hoa bo mot se lao du'cfc 4' = 4 to hcfp, neu ma hoa bo hai se lao lhanh 4' = 16 to hdp khong dii de ma hoa 20 lo;ii axit amin. Ma hoa bo ba se du'Pc 4' = 64 to hdp ihijfa de ma hoa 20 loai axil amin khong can phai ma hoa bo bon. Neu trong phan tir c6 3 loai nucleotit thi se lao diTdc 3^ = 27 bo ba ma hoa. Neu CO 2 loai nucleotit se lao diidc 2" = 8 bp ba ma hoa. ThiTc te cung co the xay ra d ciic doan gen, cac doan mARN, tARN, rARN chi co 2 hoac 3 loai nucleotit. Cau 6: Tif ciic dac diem cua mii di truycn co the suy ra dieu gi? Vi sao ma di Iruyen co cac diem do? HU('fng dan - Neu ma di iruyen goi len nhau thi se dan den ket qua gi? (Cac axit amin trong chuoi polipeplit se nhu" the" nao?) - Neu ma di truyen khong cx) tinh dac hicu thi co can den ma bp ba khong? 8 Cty TIMHH MTV DVVH Khang Vigt - Tai sao co the xay ra hien tu'png nhieu bp ba ciing msi hoa mpl axil amin? Neu so loai axit amin bang hoac Idn hPn so bp ba ma hoa thi dieu nay co the xay ra khong? - Tijf ccic dac diem ciia ma di Iruyen co ine suy ra: Trinh tu" siip xep cac bp ba trong gen khong go'i Icn nhau mdi co the quy dinh Irinh tif sitp xep cac axit amin trong chuoi polipeplit. TiT do m6i co the co tinh dac tru'ng ciia ADN, ciia protein. Tir dac tinh phd bie'n cua ma di Iruyen co the giai thich nguon goc thong nhcft cua sinh gidi cf miJc phan luT va so loai axit amin cua moi loai dcu nho hPn 64. Cau 7: Vi sao ADN co kha nang tai ban va lai ban mpl each chinh xac. HU(fngddn - Vi ADN CO cau true mach kcp. lien ket giifa cac nucicotit Iren hai mach dcfn la lien kc'l hidro (lien ket yeu). Cac nucleotit giiJa hai mach ddn lien ket vdi nhau theo nguyen lac bo sung. Qua trinh lai ban dicn ra theo nguyen lac bd sung va ban bao ton. Cau 8: ling \6\l amin md dau la Melionin co may bp ba ma hoa? Co 2 each trii Idi sau: • > a) Co 1 bp ba ma hoa ,. b) Co 3 bp ba ma hoa • l • Hay cho bie'l cau tra Idi nao dting? Hiidng dan - Ne'u noi Melionin co 1 bp ba mii hoa co nghia la trong 64 bp ba ma hoa thi Melionin chi co 1 bp ba ma hoa (trong 20 loai axit amin chi co 2 loai la Melionin va Triptophan chi co mot bp ba ma hoa, con lai deu co 2 hoac nhieu bp ba ma hoa, nhieu nha't la Aegimin co den 6 bp ba ma hoa). - Neu noi Melionin co 3 bp ba ma hoa co nghla la iJng vdi Melionin Ihi co 3 bp ma nam trcn phan tiV: TAX nam tren ADN, AUG nam Iren mARN va UAX nam tren lARN. Noi each khac la: Melionin co bp ba ma goc (Triplet) la TAX, bp ba ma sao (codon) la AUG va bp ba doi ma (anticodon) la UAX. • Noi chinh xac thi A irii Idi dung hPn B vi TAX, AUG, UAX deu la mpl trong 64 bp ba ma hoa. Cau 9: Nguyen lac trong ccJ chenhan doi ADN la gi? HiiAng dan - ADN CO khii niing nhan doi de lao thanh 2 phan tu" ADN con gidng nhau va gio'ng vdti ADN mc. - Qua irinh nhan doi ADN d te bao sinh vat nhan sP, sinh vat nhan thifc va ADN ciia virul (dang sPi kcp) dcu thco nguyen utc bd sung va ban bao ton. Cau 10: Phicn mii lii gi? Dicn ra d dau? Co nhiJng yeu id niio tham gia? ChiJc niing ciia cac yeu id do? Hicn lu'png gi xiiy ra khi kcl ihiic phicn mii? HUifng dan ' + Phicn mii lii sif idng hpp ARN. 6 sinh vat nhan thifc, qua trinh long hpp mARN dicn ra trong nhan tc biio, cf ki U-ung gian, liic nhicm sac the cf dang dan xoan. 9 Ca'm nang ti; fin va luy§n thi Sinh hgc - Phung Duy D6ng + Cat- yen lo' tham gia: - Mach ma goc 3' -> 5' ciia gen lam khuon. - Enzim ARN polimcraza xiic tac qua trinh long hctp bang each: Bam vao VLing dieu hoa lam gen lhao xoiin, tri/dt doc iheo mach ma goc lit diem khdi dau den diem kel ihiic cua mach ma goc theo chicu 3' -> 5' de long hrip nen mARN Iheo nguyen lac bo sung (A - U, G - X) iheo chieu 5' 3'. + Sau phien ma: - Phan lii" mARN du'dc giai phong, gen dong xoan, mARN ra le'bao chal de lam khuon dich ma ngay (d le bao nhan sd) hoac cal bo cac intron, no'i cac exon lai Ihiinh mARN Iru'dng lhanh mdi roi mdi ra te bao chat lam khuon djch nifi (te bao nhan Ihi/c). Cau 11: O giai doan hoat hoa trong qua trinh dich ma da xay ra nhiJng hicn Milng nao? Co nhCfng yeu to nao tham gia? Vai tro ciia cac yeu to do? San pham ciia giai doan nay la gi? Hiidng ddn + Co 2 hicn tu'c^ng xay ra la: - Float hoa axil amin. - Lien ket giiJa tARN vc'li axit amin tU'dng iJng da difdc hoat hoa tao lhanh phiVc he aa - lARN. + Yeu lo' tham gia: - ATP cung cap niing lifcfng de hoat hoa axil amin va lien ket vdi lARN. J - Cac enzim tham gia gdm: Enzim xuc lac lien kel giffa axit amin vdi ATP de lhanh axit amin hoat dong Enzim xuc lac lien kel giiJa lARN vCl\t amin tiTdng iJng da du'dc hoat hoa de tao lhanh phiJc he aa - lARN. + San pham ciia giai doan nay la cac axil amin da dUdc hoat hoa va phiJc he aa - lARN. Cau 12: O giai doan md dau trong long hdp chuoi polipeplit da xay ra nhiJng hien lu'dng nao? HUdng ddn Cf giai doan mc'^ dau c6 3 hien tifdng xay ra: - Tieu phan be cua riboxom nhan biel va lien kel vdi mARN d vi iri dac hieu, gdm codon m& dau. - Anlicodon ciia phitc hdp Met - lARN khdp bd sung vdi eodon md dau. - Tieu phan Idn ciia riboxom kel hdp tao riboxom hoiln chinh, s;Tn sang long hdp chuoi polipeplit (Theo SGK Sinh hoc Idp 12 - Chu'dng trinh chuan) (Thirc ra riboxom gan vdi codon md dau vii bat dau dich ma lai vi tri P rdi dich ma lai vi tri A tren riboxom, lien kel peptil giiJa 2 axil amin du'dc lhanh lap, lARN (da Uich khoi axil amin ml^ dau) rdi khcM ribom ihi riboxom mdi chuyen sang codon liep Iheo de liep Uic dich ma). 10 Cty TMHH MTV DVVH Khang VIM Cau 13: CJ giai doan keo dai chuoi polipeplit da xay ra nhSng hien lu'dng gi? HU('iiigddn i: i ^ Dau lien: - Anlicodon ciia phi'fc hdp aai - lARN khdp bd sung vdi codon Ihir nha'l. - Enzim xiic Uic lien kel peptil giCa axil amin ihuf nha't (aai) vdi axit amin md dau (Melionin). - lARN (da tiich khdi axit amin mi^ dau) rdi khoi riboxom. r Sau do: riboxom chuyen dich lij'ng nac, moi nac iJng vdi mot codon va qua trinh dich ma lai xiiy ra Wcing ur tren (Anlicodon ciia phiJc hdp aa - lARN khdp bd sung vdi codon liA^ng irtig, enzim xiic lac lien kel peptil, lARN rdi khdi riboxom). Cau 14: (5 giai doan kel thiic da xay ra nhifng hien Wdng gi? Huong ddn : ( - Qua trinh djch ma diJng lai khi riboxom liep xiic vdi ma ket thuc - Axit amin md dau du'dc cat khdi chuoi polipeplit (nhd enzim dac hieu) - Chuoi polipeplit hinh lhanh cac cau trilc bac cao hdn Ird lhanh protein hoiin chinh. Cau 15: Poliriboxom du'dc hinh lhanh nhu'the nao? Y nghia ciia no? ? - RiboxOm ihi? nhal chuyen dich du'dc 50 - IOOA" thi riboxom IhiJ hai gan vao mARN, liep theo la riboxom ihir 3, thi? 4, (thifdng cd lii 5 - 20 riboxom) chiing tao lhanh mot nhom riboxom ciing tham gia dich ma trcn mdt phan lit mARN. - Y nghia: Tong hdp lien liep du'dc nhieu phan lii' protein cijng loai, lam tang hieu sua't long hdp. Gin chil: De de nhd cac em nen chia ra nhu' sau: 1. Riboxom giin vao mARN lai codon md da xay ra nhiJng sir kien gi? Da xiiy ra 3 su' kien: - Dich ma axil amin md dau va axil amin ihii' nhal (^(tog ling vdi 2 vi \xi P v;i A) - Enzim xuc uic hinh lhanh lien ket peptil giffa 2 axil amin. - lARN (da tach khdi aa md dau) rdi khdi riboxom. 2. Riboxom chuyen dich lifng nac, 1 codon de liep tuc dich ma lu'dng tif Iren. 3. Riboxom gap ma kel thiic thi difng dich ma, axit amin md dau bi ciil bd va chuoi polipeplit hinh lhanh cac ca'u Iriic bac cao hdn. Cau 16: Qua Irinh djch ma xay ra d dau, liic nao, c6 nhifng yeu to" nao tham gia, vai Ird ciia mdi yen to? San phifm hinh lhanh? Y nghia ciia qua trinh dich ma? HUdng ddn - Xay ra trong tebao chat, lai cac riboxom, ngay sau khi phien ma, liic c6 mat mARN. - Ciic yeu td^ tham gia: + mARN: Lam khuon long hdp protcm . ' ' + Nguyen lieu: Ciic axit amin ur do. i,. • • + ATP: Cung cap nang iifdng. „ ,11 Ca'm nang tu an va luygn thi Sinh hgc - Phung Duy B6ng + Cac cnzim lham gia enzim: xiic Uic lao lhanh phiJc hdp aa - lARN; cnzim xilc Uic lien kel giffa axil amin vCl'i ATP. cnzim xiic tac lao lhanh lien ket peplil; enzim xiic lac qua Irinh cat bo axil amin md dau khoi chuoi polipcplil. + Riboxom: Can vdi mARN lai vi tri dac hieu de lARN bat dau dich ma; lam khung dd mARN. + Phtfc help aa - lARN va khung dO codon - anticodon; chuyen dich Iren mARN de keo dai dich ma. + Poliriboxom: Tang hieu suat long hcfp protein. + lARN: mang axil amin den riboxom va tie'n h;mh dich ma (anticodon khc'lp bd sung \xfi codon lifting vCng). San pham la mach polipeptil. Y nghTa: Ma di Iruyen diftjc dich lhanh trinh tiTcac axil amin trong mach polipeptil Cau 17: Mo'i lien quan giifa gen v('1i qua Irinh phien ma, dich ma. Hitc'fng dan - Gen mang thong tin cau triic protein (thong tin di Iruyen). Thong tin di Iruyen dift.lc ma hoa trong gen biing ma hoa bo ba. - Ma di Iruyen trong gen dUdc phien ma .sang mARN iheo nguyen ta'c bd sung. Do do lhanh phan, so lu'dng va tral lir sap xep cac bo ba ma hoa trong gen (triplet) quy dinh lhanh phan, so krong va Irat lu" sap xep cac codon trong mARN. - Ke tiep sau qua trinh phien ma la qua Irinh dich ma va mii di Iruyen trong mARN du'dc dich ra lhanh phan, so lUcing va trat tif sap xep cac axit amin trong chuoi polipeptil. Do do siT gifii ma mARN chinh la giai ma gen. Nhu" vay mdi lien quan giifa gen vc'Ji qua trinh phien ma, dich ma chinh la mdi lien quan giiJa gen - mARN - protein ma ban chat la: Thanh phan, so iu'dng, trinh tif sap xep cac bo ba ma hoa trong gen quy dinh thanh phan, so' lu'dng va trinh tif sap xep cac codon trong mARN tif do quy djnh lhanh phan, sd lu-dng vil trinh tir sap xep cac axil amin trong chuoi polipeptil. Ctiu 18: Co bao nhieu loai gen? Co cac each Irii \^^'\: a) Gen c6 nhieu loai nhu'gen cau triic, gen dieu hoa, b) Ve chifc nang c6 gen cau Iriic, gen dieu hoa, gen tang cu'dng, gen ba't hoal, c) Co v6 sdloai gen. Hay phan tich xem cac each Ira Ifli tren da thoa man vdi yeu cau ciia cau hoi khong? Co the Ira Idi nhif the niio cho day dii, chinh xac. HU(hig dan - Theo each c) life la can cu" vao ca'u tao da phan ciia gen de suy ra linh da dang ciia gen. - Theo a) va b) li'rc la can cir vao chi?c nang de ke ra vai loai gen. Co the tra Uii can hoi tren nhif sau: 12 Cty TNHH MTV DVVH Khang Vigt 1. Ve call tao: - Co gen phan manh, gen khong phan miinh. ' ' ' - Thanh phan, sd lifting va Irinh lif sap xep cac nuclcolil khac nhau da tao ra v6 so' loai gen. Mdi loai gen c6 lhanh phan, sd^ lu'dng va trinh tu" sa'p xep cac nucleolil dac iru'ng. - Can true khong gian ciia gen ciing khac nhau nen cung lao ra nhieu loai gen khac nhau: nhu" gen mot sd chiing virul (gidng ca'u true ARN), gen sinh vat nhan Ihifc (eo cii'u true xoan kep), gen Irong nhan (tren NST), gen ngoai nhan (trong lap thc\i thc\, ecH-a'u trik mach xoan kep, thang hocic vong. 2. Ve chufc nang: - Co v6 sd loai pdtein nen c6 v6 sd loai gen cau true khac nhau. - Co rat nhieu cMc nang di Iruyen khac nhau nen cung co rat nhieu loai gen khac nhau nhu" gen ca'u Irilc (tdng help protein, mARN, lARN, rARN), gen dieu hoa, gen khdi dong, gen tang ciTcIng, gen bii'l hoal, gen gay chel, gen nhiiy, Cau 19: Cac phan tu" mARN c6 gi gidng nhau, va khac nhau? Tai sao? HUdngd&n 11^/ - Ve cii'u triic: Cac phan tu" mARN deu gdm diem khdi dau, doan chiJa ihong tin ma hoa axil amin va diem ket thijc do qua trinh phien ma du'dc lien hanh tir diem khdi dau vii eha'm dift d diem ket ihiic ciia gen. Ci dau 3' deu co mdi Irinh liT nucleolil dac hieu (khong dUcIc dich ma) de riboxom nhan biet va ga'n vao. Cac mARN deu du'ilc ca'u lao bdi cac ribonucleotil, du'cle phien ma lif cac nucleolil. NhUng do lhanh phan, sd lu'cing, trat tu" sap xep cac nueleolil co ra't nhieu each khac nhau, nen co rat nhieu loai gen ca'u true long help ra rat nhieu loai mARN khac nhau. - Ve ehii'c nang: Moi phan tu" mARN deu du'cle dung lam khuon de tdng help ra pre')tein. pre'nein ce'i nhieu ehii'c nang nhu'ng khc^ng the ne)i mARN ce) nhieu chiJc nang. cau 20: So siinh qua trinh nhan doi ciia ADN va phien ma tdng help ra mARN e'^ sinh vat nhan thufc. , , , ^ HUOngddn 1. Giong nhau: ; . - Dieu xay ra d ki trung gian. - Chieu tdng help deu ngifelc chicu ve'li chieu mach khuon. - Deu lien kel cac nucleolil trong mc)i triTdng diTa tren cac nucleolil trong mach khu(')n theo nguyen lac bd sung. - - Nguyen lieu deu la cac nucleolil tif do. - - Deu phai CO enzim dac Iru'ng xiic lac. ijv J,' Ca'm nang tu fin v4 luy^n thi Sinh hoc - Phung Duy Ddng 2. Khac nhaii; Hoc sinh tuphdt trien kien thi'fc theo f^(/i v sau: - Vc nguycn lieu siV dung khac nhau nhu" the' nao? - Vc en/im xiic tac khac nhau the'nao? - Ve nguyen tac bd sung CO khac nhau khong? " , . f^'H:- - Ve c(l che khac nhau nhu" the niio? - Ve ket qua c6 gi khac nhau? Cau 21: Hay giiii thich vi sao phu nff khong c6 rau d cam, khong c6 ria d mep, va dan ong hlc nho van khong c6 rau, ria nhu'ng den khi Irifdng thanh lai c6 rau, ria (Can ci'r vao chifc nang cua gen, dicu hoa hoal dong gen de tra Icli). Cau 22: VI sao noi: Giai mii mARN cung chinh la giai ma ADN (Can ctJ" vao moi quan he giifa ADN - mARN de trii Idi). Cau 23: Vi sao phan \6n sinh vat nhan thifc tao ra mARN chu'a siJ'dung djch ma ngay difdc, con mARN du'Oc tao ra tif sinh vat nhan sd lai siJ dung dich ma ngay du'Oc (Can ciV vao viing ma hoa ciia gen cau true de tra IfJi). Cau 24: Co phai tat ca moi gen deu chu'a day dii ca 4 loai nuclcotit la A, T, G, X khong? Gia su' gen chi c6 2 loai nucleolit ihi mii hoa du'c.^c may loai axit amin. Giil sijfmARN chi c6 3 loai ribonuclcotil thi se ma hoa diTcfc bao nhieu loai axit amin, H If (fug dan - Vi gen chi la 1 doan ma cua phiin tii" axit nucleic nen c6 the khong c6 dij ca 4 loai nuclcotit. - Ciin ci? viio cong ihiJc to hdp de tim ra c6 bao nhieu to hdp bo ba tijr 2 loai nuclcotit, tir3 loai nuclcotit, tir4 loiii nuclcotit Cau 25: Hiiy giai thich tai sao mARN thifdng bi cac enzim phan hiiy sau khi long hdp xong protein (vi de khuon luon mdi, khong bi hif hong do SIJT dung lau hay do tac nhiin khac giiy ra). Cau 26: Vi sao gen khong diTdc su' dung liim khuon trifc tie'p tdng hdp protein? (vi thong tin di truyen ciTc ki quan trong, du'dc bao quiin to't trong NST, ti the, , du-dc gicr gin ciin thiin. No la ban ma gdc c6 the dilng ban ma sao (mARN) thay the. Bcln sao cQng chi dirdc siV dung mot Ian, de diim bao ti'nh chinh xac cua thong tin di truyen. Cau 27: Co bao nhieu loai ARN. Chung c6 gi gidng nhau, c6 gi khac nhau? Tai sao? Hi((fng dan + VI deu du'dc tdng hdp tuf mot niach cua gen nen cac loai ARN nhu' mARN, tARN, rARN deu c6 cii'u triic mach ddn, deu du'dc cau tao tif cac ribdnucledtil. Thanh phan, so' krdng va trat tif sap xe'p cac ribonuclcdtit deu do gen quy dinh. + Qua trinh tdng hdp cac loai ARN deu theo cd chc tu'dng ti/ nhau. + Chudi ribonucleotit hinh thanh xong se bien ddi ca'u hinh, hinh thiinh ca'u true dac tru'ng cua tiTng loai, phu hdp chifc nang cua moi loai. Vi vay cau true cua chilng khiic nhau. Cty TNHH MTV DVVH Khang Vi§t - mARN difdc diing lam khuon tdng hdp protein nen c6 cii'u tao mach thang, CO vi tri dac hieu niim gan codon md dau de riboxom nhan biet vil Hen ket vdi mARN. c6 bo ba md diiu de tARN nhan bic't va mang axit md dau den dung vj trI. Vil CO bo ba ket thuc de riboxom nhan biet va difng dich mii. - tARN liim nhicm vu van chuyen axit amin den riboxom vii lam nhiem vii dich mii nen mot dau ciia no c6 trinh lif nuclcotit dac hieu de axit amin tu'dng itng nhiln biet va lien ket vdi tARN. mot d;tu c6 bo ba doi mii (anticodon) de tARN nhiln biet va lien ket bd sung vdi codon tu'dng iJng. - rARN lii thiinh phjln chii ye'u ca'u tao ra ribdxdm nen chung c6 ca'u tao dac tru'ng thuan Idi cho vice lien ket vdi protein de tao thanh riboxom. + Vi giiJ ciic chu'c nang quan trong khac nhau nen ddi song cua cac loai ARN Cling khac nhau: Sau khi tdng hdp xong protein, mARN Ihu'dng du'dc cac enzim phan hiiy, con tARN vii cac rARN difdc sufdung qua vai the he te bao. Cau 28: Hay suy luan xem sif nhiin doi cua ADN c6 lien quan nhu' the' niio vdi sV tcii ban ciia gen, vdi sir phan chia te bao, vdi dot bie'n gen, vdi dot bie'n nhiem sac the? HU(fngddn Sir nhan'ddi cua ADN dan de'n su" nhan ddi (tai ban) ciia gen, sir nhiin ddi ciia ADN tao dicu kien cho nhiem sac the nhan doi, chuan bi cho su" phan bao. Cac tac nhan dot bien tac dong viio qua trinh nhan doi cua ADN c6 the gay dot bie'n gen. Dot bien ca'u triic nhicm siic the dan tdi thay ddi vj tri cua gen, mat can bang gen. Cau 29: Khi tien hanh nhiin ddi ADN trong d'ng nghiem phuc vu cho nghien ciTu va iJng dung thirc tien ngu'di ta thay cd nhu'ng doan ADN ngiin khoang vai tram cap nuclcotit. Hien tu'dng niiy du'dc giai thich nhu? the nao? Hi((fng ddn Do sir tdng hdp mach ADN Iren mach khuon 5' -> 3' xiiy ra ngat quang tao ra cac dojin ngan, nhu'ng thic'u enzim nd^i ligaza nen cac doan ngan khdng du'dc ndi lai vdi nhau tao thanh mot mach hoan chinh. Cfiu 30: Nhd dau enzim ARN polimeraga c6 the thi/c hien cac chu'c nang cua no trong phien ma tdng hdp mARN. HUifng ddn Trong qua trinh phien mti, enzim mARN polimeraza c6 cac chu'c nang sau: - Bam vao viing dieu hoa liim gen thao xoan va bat dau phien ma ARN polimeraza thirchien chu'c nang nay lit nhd trong viing dieu hoa cua gen ca'u true CO mot trat tir nuclcotit diic hieu goi la viing khdi dong. Nhd trinh tir nay ma enzim ARN polimeraza co the nhan bic't, bam vao va bat dau tdng hdp mARN tai diem khcfi dau. - Tdng hdp phiin tuT mARN: Sd dl ARN polimeraza thiTc hien chu'c nang nay la nhd nguyen tac bd sung. - Dirng phien ma: Nhd vijng ke't thiic cua gen mang tin hieu ke'l thiic. dm nang lu 6n Iuy6n thi Sinh hpc - Phiing Duy Pgng CSu 31: Noi rang: phicn ma lii qua tnnh long hdp mARN dung hay sai? (dung nhu'ng chu'a di'i vi phicn ma con tao ra tARN va rARN niJa). Cau 32: Bo ba mii hoa va ma hoa bp ba co gio'ng nhau khong? Tai sao? Bo ba ma hoa c6 hen quan den tinh da dang ciia sinh vat khong? HU(fng dan - Khong gio'ng nhau: Ma hoa bo ba la each ma hoa, con bo ba ma hoa la mot to hcfp cija each ma hoa bo ba tii" nhfJug yc'u to'cho bie't. Vi du: Neu eo 4 nuclcotit, se c6 4^ = 64 bo ba ma hoa, (tiJc la 64 to hdp bp ba tiT 4 loai nucleotit). Neu c6 3 loai nuclcotit thi so' to' hdp bp ba (so' bp ba ma hoa) se la 3' - 27 (ixic la 27 bp ba ma hoa), -'• Thanh phan, so' lu'dng va trat tif sap xe'p ciia cac bp ba ma hoa trong phan tu" ADN CO rat nhieu each khac nhau nen da tao ra v6 so' loai ADN khac nhau. Do la cd sd phan tu" ve tinh da dang cua sinh gidi. CAu 33: Chi c6 - 64 bp ba ma hoa, trong do c6 3 bp ba ket thuc khong ma hoa axit amin nao. Lam sao c6 the ma hoa cho v6 so'loai protein ciia tat ca mpi loai sinh vat. Hiiiiiigddn 61 bp ba ma hoa ma hoa du'dc 61 loai axit amin. Tat ca cac loai sinh vat khong CO loai nao c6 so' loai axit amin Idn hdn 61 (suy ra tij" dilc diem tinh phd bie'n cua ma di truyen). Ta't ca cac sinh vat, protein du'dc cau tao tif 20 loai axit amin. Vi du, d ngiCdi c6 khoang 250000 gen da ma hoa cho rat nhieu phan tu" protein cung chang dung hc't 61 bp ba ma hoa. Cau 34: Tu" dac diem cua ma di truyen c6 the suy ra dieu gi? Hiidiig dan - Ma di truyen khong goi len nhau nen cac axit amin trong chuoi polipeptit khong goi len nhau. Gia siir ma di truyen khong c6 dac diem nay thi dan den ke't qua gi nffa. - Ma di truyen co tinh pho' bien c6 the suy ta't ca cac loai protit cua mpi loai sinh vat deu co chung mot ma di truyen va suy ra nguon go'c thong nha't cua sinh gidi d cap dp phan tu". - Ma di truyen co tinh thoai hoa, (co the co nhieu bp ba cung ma hoa mot loai axit amin) suy ra so'loai axit amin phai nho hdn so'bp ba ma hoa. ' ' ' ' - Ma di truyen eo tinh dSc hieu (mot bp ba ma hoa chi ma hoa cho mot loai axit amin) suy ra so'loai axit amin phai it hdn hoac bang so bp ba ma hoa, va ma di truyen khong the la ma hoa bp hai. Cty TNHH MTV DWH Khang Vigt CSu 35: Sach iiiao khoa Sinh hoc Idp 12 ~ Nang cao co ghi: "Qua trinh phicn ma tien hanh tCr diem khdi dau va cham di?l d diem kel thiic ciia gen tren ADN". Hay cho bicl diem kh(":fi dau, diem kcl thiic co phai la mot diem khong? Chung CO tu'(ing I'rng vdi ma mc'^ dau va ma kct thiic tren gen khong? Chung nam vi tri nao tren gen? HUOngddn - Diem khdi dau khong tifdng ifng vdi ma nu'-f dau vii diem khcii dau nam d vung khdi dpng trong vimg dieu hoa ciia gen. Do la mot trinh tu" nucleotit dac hieu giiip en/.im ARN pohmera/.a nhan bie't vii hen kel de khdi dpng qua trinh phicn ma tii" diem khdi dau ciia gen, con ma md dau nam d vi tri dau lien trong vimg ma hoa ciia gen. - Diem kcl thiic cung khong tifcing I'fng vdi ma ke't thuc, vi neu qua trinh phicMi ma cham diH d ma ke't thuc thi mARN se khong co codon ke't thuc. NhU' viiy diem ket ihiic phai la diem cud'i cung ciia gen. Cau 36: Sach giao khoa Sinh hoc Idp 12 - Nang cao cho bie't: "riboxom lien kct vdi mARN tai codon md dau va qua Irinh dich ma du'dc bat dau". Sach giao khoa Sinh hoc Idp 12 - Chuan cho bie't: "lieu phan be riboxom g^n vdi mARN d vi tri dac hieu n;lm gan codon md dau, tARN mang Mclionin bd sung chinh xac vdi codon md dau. Ticu ddn vi Idn ciia riboxom kct hdp tao thanh riboxom hoan chinh san sang long hdp chuoi polipeptit". NhU' vay 2 cuon sach giao khoa co sir khac nhau. Hay phan lich nhiJng kien IhiJc tren va cho bie't y kie'n ciia minh. <• ••'•'^'t:y^;'m Hitdngddn Neu riboxom lien ke't vdi mARN d vi tri gom codon md ditu, thi axit amin md dau khong du'dc "long hdp" tai riboxom. Do la dieu chu'a hdp li. "Lap rap" xong axit amin md dau mdi s;Tn sang long hdp chuoi polipeptit, cung la dieu v6 li vi nh\i vay ngay ban dau chuoi polipeptit da khong co axit amin md dau. Thirc ra, tren riboxom cd 2 vi tri P (peptit) vii A (amin). Axil amin md dau va axit thu^ nha't deu du'dc "lap rap" tai vi tri P va A nam trong riboxom. Sau khi hinh thanh lien ke't peptit riboxom mdi chuyen dich sang codon liep theo dc tARN dich ma liep. Nhu' vay, qua Irinh long hdp chuoi polipeptit bill dau lif axil amin md dau chu" khong phai "lap nip" xong axit amin md dilu mdi s3n sang tdng hdp chuoi polipeptit nhu* SGK Sinh hpc Idp 12 chuan vie'l. Cfiu 37: Tir nhu'ng hieu bie't ve gen trong phan niiy hay giiii thich cd che' di truyen d cap dp phan tu' (gen, ADN). ^ . HUcIng ddn - Gen cii'u true lii mot doan ciia phiin tiV axil nucleic. 6 sinh vat nhan thiTc, gen cau true co mach xoiin kep di/dc cfui tao tir 4 loai nucleotit theo nguycn lite bd sung (A - T, G - X) 11 Ca'm nang tu 6n va luygn thi Sinh hgc - Phiing Duy D6'ng Gen (ADN) la vat chat di truyen d cap do phan tu", chiJa thong tin quy dinh cau true cua protein (thong tin di truyen) thong tin di truyen diTdc ma trong gen bang ma hoa bo ba. , ^ <«, - Nh5 ADN CO cau true 2 mach ddn va lien ket gii?a'2 mach ddn la lien ket yeu (lien ket hidro) va cac nucleotit giffa 2 mach ddn lien ke't vdi nhau theo nguyen tac bo sung, nen ADN c6 kha nang nhan doi. ADN nhan doi theo nguyen tac bo sung va ban bao ton bao dam cho thong tin di truyen chtfa trong ADN difdc truyen qua cac the' he ADN mot each chinh xac. ADN nhan doi dan tdi su" nhan doi ciia gen. Sir nhan doi cua ADN tao dieu kien cho sir phan bao. Nhu* vay thong tin di truyen trong ADN (gen) cua m6i te bao du'dc truyen cho the he te bao con mot each chinh xac qua cd che nhan doi cua ADN (gen). - Thong qua phien ma va dich ma thong tin di truyen chtfa trong ADN diTdc djch ra thanh: so lu'dng, thanh phan, trat tu" sap xep cua cac axit amin trong chu6i polipeptit ciia protein va du'dc bieu hien thanh nhifng dac diem ve cii'u tao va boat dong sinh li cua te bao, ciia cd the. Noi each khac chung bieu hien thanh tinh trang cija sinh vat. Cau 38: Trong cau true cua ADN c6 cac lien ke't gi? Hudng ddn Co lien ke't hidro giifa cac nucleotit gii?a 2 mach ddn, c6 lien ke't hoa tri giiJa cac nucleotit trong mach ddn (lien ke't phospho dieste) va lien ket hoa tri giifa dirdng d vi tri C so'5 (5') v6[ axil photphoric trong moi nucleotit. Cau 39: Vi sao phan tuf ADN vCra vffng chac vira linh boat? Hitdng ddn Phan tur ADN viTng chac la nhd lien ke't phospho dieste giiJa cac nucleotit la lien ke't rat vffng chac (nen khi 2 mach ddn tach nhau ra, chuoi polinucleotit van ton tai). Lien ke't hidro ra't nhieu nhtfng ne'u vSng chac thi phan tu" ADN khong the duoi, xoan tach nhau ra khi can thiet (linh boat). Mat khac so' lu'dng lien ke't hidro rat Idn citng gop phan lam cho ADN vffng chac. III. CAU HOI TRAC NGHIEM CSu 1: ADN ma cau true chi c6 mot mach gap 5 dang sinh vat nao sau day: A)Tbeankhuan B) Virut C) Vi khuan D) Ca A va B Cfiu 2: Mot so virut vat chat di truyen la ARN. Sir t^i sinh cua ARN theo nguyen tac nao? . i ^ A) Nhan doi ARN B) Sao ma ngiTdc C) Tong hdp ADN roi tir do long hdp ARN D) Bao loan 18 Cty TNHH MTV DVVH Khang Vigt Cau 3: ADN CO mach xoan kep gap cf dang sinh vat nao? ,, v A) Sinh vat nhsin thiTc B) Dong vat, thi/c vat C) Virut, vi khuan D) Dap an A la dung nha't CSu 4: ADN dang mach vong c6 cf: A) Mot so vi khuan B) Mot so virut C) Lap the, ti the D) Ca A, B, C. CSu 5: Gen la: , ^ ' • Xty A) Mot doan AND B) Mot doan ARN :-m C) Mot doan axil nucleic D) Dap an C la dung nha't CSu 6: Co bao nhieu loai gen? A) Co 2 loai gen la gen trong nhan va gen ngoai nhan. B) Co 2 loai gen la gen mach kcp va gen mach ddn. ~ - ' C) Co 2 loai gen la boat dong va gen bat boat. ,> 'u '> D) Co v6 so'loai gen, tiiy vi tri, cau tao, cbtfc nang, Cfiu 7: Tin hieu khcfi dong nam d vimg nao cua gen cau true? > "i A) Viing dieu boa B) Viing ke't thiic 1 C) Viing ma boa D) Viing van hanh '41 • Cau 8: Viing dieu boa cua gen cau true nam d vi tri nao? • / <' A) Dau liiach ma goc B) Dau mach bd sung f>ri .5 C) Cudi mach ma gdc D) Cudi mach bd sung. n "3«: C&u 9: Vimg dieu hoa ciia gen cau Iriic c6 chiJc nang gi? i*;: A) Dieu hoa boat dong gen B) Kbdi dong boat dong gen C) Khcli dong va kiem soat phien ma. D) Cham dut phien ma. ; s Cau 10: Viing ma boa cua gen cau true c6 chiJc nang gi? *. ' \ A) Ma boa cac axil amin. <j f (u \i J " -hi i B) Quy dinh cac axit amin. ' i f C) Mang thong tin ma boa cac axit amin. > ( D) CaA, BviiC. Cau 11: Viing ke't thiic CO cbtJc nang gi? ' M K A) Ket tbue phien ma B) Ket tbiie dieb ma ' ' , i' C) Mang tin bieu ket tbue phien ma D) CbiJa ma ke't thuc ' • >, ' CSu 12: Diem kbdi dau cua gen nam 5 dau? .< i A) d ma md dau B) d codon ibiJ nha't C) Diem dau lien cua gen D) (J viing kbdi dong CSu 13: Diem ket tbue ciia gen nam d dau? • *; A) d vimg ke't tbue f B) 6 sinh vat nhan tbirc C) d diem cudi cung cua gen D) 6 virut ;v., /, , CSu 14: Gen phan manh c6 d sinh vat nao? A) 6 sinh vat nhan sd B) 6 sinh vat nhan thirc C)6vikbuan D) 6 virut 19 Cam nang til fin vS luyen thj_^nh_hQC - Phiing Uiiy Dniig CSu 15: Ma di iruyen la gi? A) La bo ba ma hoa. B) La ma hoa bo ba. C) La thong tin di Iruyen du'dc ma hoa. D) Ca A, B, C. Cau 16: Vi sao thong tin di truycn phai ma hoa bang ma "bo ba? A) Vi CO 4 loai nuclcotit. B) Vi CO 20 loai axit amin. . > * C) VI ma hoa bo hai khong du dc ma hoa 20 loai axil amin. D) Ca A, B,C. Cau 17: Ma hoa bo ba va bp ba ma hoa c6 giong nhau khong? Cciu Irii Idi nao dung nhii't? A) Gio'ng nhau ' B) Khac nhau C) Giong nhau vi dcu la each ma hoa D) Khac nhau vi ma hoa bo ba la each ma hoa con bo ba ma hoa la mot to hdp cua cac ma hoa bp ba. Cau 18: O viing dicu hoa cua gen c6 chifa ma di truyen khong? A) Khong chiJa vi khong ma hoa axit amin. B) Khong chila vi mang tin hieu khdi dpng va kiem soat qua trinh phien ma. C) Co chuTa ma di Iruyen nhu'ng khong chu'a axit amin. D) CaAvaB. Cau 19: Vung ke't thiic c6 chu'a ma di truyen khong? ' A) Khong chu'a vi khong mang thong tin ma hoa cac axit amin. B) Khong chu'a vi khong lam nhiem vu ma hoa axit amin. C) Khong chu'a vi mang tin hieu ket Ihiie phicn ma. D) Co chu'a ma di truyen nhu'ng khong ma hoa axit amin. Cau 20: Ma ket thuc (bp ba ke't thuc) c6 chiJc nang gi? A) DiYng phien ma B) DiTng dich ma C) Mang tin hieu dijfng phien ma D) Mang tin hieu diifng dich ma Cau 21: Ma md dau c6 chtfc nang? A) Mang tin hieu md dau phicn ma B) Mang tin hieu md dau dich ma C) Mang tin hieu ciia axit amin thu" nhat D) Chu'a thong tin ma hoa axit amin md dau Cau 22: Ma di truyen trong ADN du'cic phien ma sang mARN nhd cd che'nao? A) Nhd cd che phien ma B) Nhd cd che tdng hdp mARN C) Nhd cd che djch ma D) Nhd cd che tong hdp ARN CSu 23: Ma di truyen trong ADN du'cic giai ma nhd cd che' nao? A) Nhd cd che dich ma. B) Nhd cd che tdng hdp protein. C) Nhd tARN van ehuyen. D) Ca A, B deu dung. 20 Cty TIMHH MTV DVVH Khang ViSt CSu 24: Vi sao dau 5' c6 mot trinh tU nuclcotit dac hieu khong diTdc djch ma? A) Vi khong chufa thong tin di truyen. B) Vi dich ma bat dau d codon md dau u'ng vdi bp ba dau tien trong viing ma hoa. C) VI qua trinh phien ma bat dau tifdiem khdi dau nam tru'dc codon md dau. D) Ca B va C. Cau 25: Sir kicn cat bo cac intron va ndi cac cxon lai xay ra luc nao 6 sinh vat nhan thyc? A) Liic phien ma B) Lilc bat dau dich ma C) Sau phien ma D) Liic dich ma. CSu 26: Qua trinh phien ma xay ra theo chieu nao? A) Chieu 3' -> 5' cua mach ma gdc B) Chieu 5" 3' ciia mach ma gdc C) Chieu 3' -> 5' ciia mach bd sung D) Chieu 5' -> 3' ciia mach bd sung. Cau 27: Chieu ciia mARN diWc tdng hdp • A) Chieu 5' 3' cua mach ma gdc B) Chieu 3' -> 5' ciia mach ma gdc C) Chieu 5' -> 3' ciia mach ma sao D) Chieu 3' -> 5' ciia mach ma sao. Cau 28: Vi sao can c6 giai doan hoat hoa ciia axit amin: A) Vi axit amin tiT do khong 5 Irang thai hoat dpng. ^ B) Vi axit amin tU do chu'a lien ket vdi tARN tUdng u'ng. C) Vi can tao ra phiJc he aa - tARN de van chuyen axit amin den vi tri tu'dng m u'ng tren mARN. 1 D) Vi cii A, B, C. Cfiu 29: Riboxom c6 chiJc nang gi: A) Ndi dich ma. B) Vira la ndi dich ma vifa la khung dd giiTa. mARN - aa - lARN va giiJa • codon - anticodt)n liic dich ma. • C) Chuyen dich tren mARN de tARN dich ma. P D)Ca A, B, C. Cau 30: Qua trinh dich ma bat dau tiT dau? Kcl thiic d dau? A) Bat dau d diem khdi dau va cham dirt d diem ket thiic. B) Bat dau tiTcodon md dau va kcl thiic khi riboxom tiep xuc vdi ma ket thiic. C) Ba't dau d vimg khdi dpng, ket thiic d viing ke't thiic. D) Ca AvaCdeudiing. Cfiu 31: Qua trinh dich ma diTng lai khi: :/; ; s 'h A) Dot bien lam xuiit hien ma kcl thuc , „. -i "i : B) Khi riboxom tiep xiic vdi ma ket thiic C) Khi riboxom tiep xuc vdi bp ba UAA hoac UAG hoac UGA D) Ca A, B,Cdeudiing. > ; - [...]... cap NST thiTdng Tren moi cap NST chuTa 2 cSp gen Trong loai tha'y cd 2 loai giao tuT AB DE va ab de Cho bie't khong cd dot bie'n 1 Quy luat di truyen nao lam cho so loai giao tiJ sinh ra la it nha't? Hay viet kieu gen ciia tc bao sinh due 2n sinh ra cac loai giao tuf do va thanh phan gen cua cac loai giao tuf sinh ra tif te bao sinh due dd • 63 Ca'm Cty TIMHH MTV nang tu 6n va luy$n thi Sinh hpc... bao sinh due cdi sd khai Ne'u moi te'bao sinh due dUc sd khai deu nguyen phan lien tiep 3 ddt, te'bao sinh due sd khai cai nguyen phan lien tiep 4 ddt Dap so: 1 So te bao sinh tinh So te bao sinh tru'ng 8000 16000 - , '-r;?-;-'-' • : ;-;rv,>, „ 2 So te bao sinh due difc •' v-'ii'ir'i :'ssa\^^^•hni^Rlv•(ynt•i' • So te bao sinh due cai 10^ Bai 8: Bo NST liTdng boi cua meo 2n = 38 Tong so te' b^o sinh. .. cung cap cho te bao sinh due sd khai cai de tao triing • , Hiidng ddn 1 Goi so te'bao sinh tinh la X , so te'bao sinh trufng la y Ta C O he phUdng trinh: x + y = 320 ;, , 19x4x-19y = 18240 Giai he phUdng trinh ta eo so lu'dng te bao sinh tinh bang 256, va so lifdng te bao sinh trufng la 64 Suy ra so ddt nguyen phan cua te'bao sinh due dye la 8, cua te bao sinh due cai la 6 2 Theo gia thie't, so tinh U-ung... moi loai te' bao sinh due sd khai bao nhieu NST ddn mdi tu'dng du'dng de tao triJng va tao tinh trung? Ne'u c a c tebao sinh tinh dUdc tao ra lis 1 t e b a o sinh due dure Dap so': 1 Sohdptur: 128 2 So t e b a o sinh tnJng: 256 So t e b a o sinh tinh: 512 h, . kie'n thiVc da c6 de md rong kicn thiJc, phat trien nang liTc nhan thiJc. Hicn nay, de thi tot nghiep THPT, tuyen sinh vao cac trufcing Cao dang, Dai hoc mon Sinh hoc la hinh thifc . polimeraza thiTc hien chu'c nang nay la nhd nguyen tac bd sung. - Dirng phien ma: Nhd vijng ke't thiic cua gen mang tin hieu ke'l thiic. dm nang lu 6n Iuy6n thi Sinh . cho thi sinh chi phai tra Idi van tat doi vdi iCmg cau hoi. De lam to't hinh thiVc thi trac nghiem, ngoai vice on tap c6 ke' hoach, chuan hi noi dung kl thi hoc sinh