Thc hnh: Quan st cc dng t bin s lng NST

Thc hnh: Quan st cc dng t bin NST Nhm 2

A. T BiN CU TRC

nh ngha: l nhng bin i trong cu trc ca NSTBn cht: s sp xp li nhng khi gen trn v gia cc NSTTc nhn Ha hc Sinh hc Vt lPhn loi Mt onLp ono onChuyn on

KHI QUT

nh ngha: lm mt i mt on ca NSTHu qu: gy cht i vi th t binLi ch: loi khi NST nhng gen khng mong mun mt s ging cy trngV d: ngi: mt on NST 22 gy ung th mu

I-MT ON

nh ngha: lm cho mt on no ca NST lp li mt hay nhiu lnHu qu: mt cn bng gen -> c hi cho th t binLi ch: tng hot tnh enzim amilaza trong la mch -> phc v ngnh sn xut biaV d: rui gim, lp on 16A 2 ln trn NST X lm cho mt li thnh mt dt II-LP ON

nh ngha: lm cho mt on NST no t ra ri o ngc 180 v ni liHu qu: gim kh nng sinh snLi ch: to ra ngun nguyn liu cho qu trnh tin haV d: ngi: to giao t bt thng -> gy cht bo thai rui gim c 12 o on trn NST s 3 thch nghi vi nhit t khc nhau

III- O ON

nh ngha: dn n s trao i on trong mt NST hoc gia cc NST khng tng ngHu qu: gim kh nng sinh snLi ch: hnh thnh loi miV d: bnh huyt cu hnh li lim ngi IV-CHUYN OAN

B.T BIN LCH BI(t bin lm tng hay gim 1 hoc 1 s NST dn ti lm mt cn bng h gen => gim sc sng v kh nng sinh sn)

I.T BIN LCH BI NGI

1.Hi chng DownHi chng Down 95% do t bin d bi cp NST s 21,ngi b bnh Down mang 3 NST 21 trong tb (2n +1).Ngi mc hi chng Down c tm vc thp,mt n n,mt xch,mi nh tt,chn tay ngn,bn v ngn tay to,ming tr v h,cc khuyt tt v tim, d b nhim khun ng h hp,chm pht trin tr tu,tui th trung bnh thp,c quan sinh dc km pht trin (thng bt th)T n s hi chng Down tng dn vi tui ca m (m