CAU TRUC NHIEM SAC THE
Bai 7 THirC HANH: QUAN SAT CAC DANG DOT BIEN
DINH VA TREN TIEU BAN TAM THdl
MUC TIEU
- HS quan sat dugc bg NST dudi kfnh hien vi.
- Xdc dinh dugc mgt sd dang dot bidn NST tren tieu ban cd dinh.
- HS xac dinh dugc cac cap NST tuang ddng cua ngudi tren anh chup.
- Ren kl nang lam tieu ban NST va xdc dinh sd lugng NST dudi kfnh hien vi.
- Ren kl nang van dung li thuydt vao thuc tidn, nhan bidt hinh anh.
II. CHUAN B!
- G V :
+ Kfnh hien vi: 10 chide.
+ Tieu ban: Bg NST cua td bao bach cdu ciia ngudi binh thudng va bd NST ba't thudng d ngudi.
+ Tranh anh: Bd NST d ngudi cac loai.
+ Dung cu md.
+ Phim anh ve bd NST d ngudi (ndu cd).
- HS: Mdi nhdm 1 - 2 con chau chdu due.
III. CACH TIEN HANH 1. Kiem tra
- GV kiem tra phdn chuan bi mdu cua cdc nhdm.
- GV cho HS nhdc lai kidn thiic vd dot bidn sd lugng NST.
2. Trong tam
Quan sat, nhan bidt dang dot bidn sd lugng NST.
3. Bai mdi Md bai:
- GV neu yeu cdu bai thuc hanh.
- GV phdt dung cu cho cac nhdm (luu y bao quan dung cu).
- GV nhdc nhd HS cac thao tac sir dung kfnh hien vi.
- GV de nhdm "yeu khoa hgc'' gidi thieu mdu tieu ban NST cua te bao tinh hoan chau chdu due lam sdn.
Hogt dpng 1
QUAN SAT CAC DANG DOT BIEN SO LUONG NST TREN TIEU BAN CO DINH
Muc tieu:
- HS quan sat nhan bidt dugc cdc dang dot bie'n NST.
- Ren kl nang su dung kfnh hidn vi, quan sat, van dung If thuyet vao thuc tidn.
Hogt dpng cua GV -GV:
+ Treo cac tranh anh bd NST binh thudng, bd NST bat thudng d ngudi va mgt sd loai khac.
+ Phdt tieu ban mdu cho cac nhdm.
+ Neu yeu cdu khi quan sat.
- GV: Quan sat cac nhdm lam viec, nhdc nhd giiip dd nhdm cdn yeu.
- GV kidm tra kdt qua ciia cac nhdm ngay tren kfnh hien vi.
- GV yeu cdu: Thao luan chung vd kdt qua dat dugc.
- GV nhan xet, danh gia.
Hogt dpng cUa HS - H S :
+ Quan sat tranh hinh.
Mdi cd nhan quan sat ki cac tranh hinh.
• van dung If thuyet —> trao ddi nhdm nhan bidt cac dang dot bidn so lugng NST (the 3 nhidm, the 1 nhidm..).
+ Quan sat tieu ban.
• Dieu chinh kfnh hien vi.
• Dua tieu ban len kinh —> Quan sat mdu d bdi gidc rd nhdt.
• Cac thanh vien trong nhdm ddu quan sat -> trao ddi va thong nhdt nhan dang dot bidn sd lugng NST tren tieu
5an.
• So sdnh vdi tranh anh de quan sat dugc ro va chfnh xdc ban.
• Ghi chep ket qua.
- Dai dien HS trinh bay ldp ciing thao luan -> nhan xet, bd sung.
Hogt dpng 2
LAM TifeU BAN TAM THdl VA QUAN SAT NST Muc tieu:
- Ren kl nang lam tieu ban, quan sat nhan bidt.
- Van dung If thuydt vao bai thuc hanh.
Hogt dpng cda GV
- GV: Hudng ddn kl nang cho nhdm
"yeu khoa hgc''
Hogt dpng cda HS
Hogt dpng cUa GV Hogt dpng cda HS + Dai dien nhdm yeu khoa hgc gidi
thieu cdc thao tac lam tieu ban va bieu didn cac thao tac.
+ Nhdm yeu khoa hgc gidi thieu mdu tieu ban da chuan bi.
- GV yeu cdu dai dien nhdm nhdc lai cac thao tdc thuc hanh.
-GV yeu cdu:
Cac nhdm tidn hanh lam tieu ban tam thdi d chau chdu.
- GV va nhdm yeu khoa hgc quan sat giiip dd cdc nhdm, dac biet la cac thao tac tach tinh hodn, lam vd td bao.
- GV kiem tra kdt qua ciia cac nhdm ngay tren kfnh hidn vi.
- GV kiem tra xong thi cho ldp thao luan kdt qua.
- GV nhan xet, danh gia.
- HS: Ndm dugc cac thao tac.
+ Dung keo cdt bd chan, cdnh ciia chau chdu.
+ Tay trdi cdm phdn ddu nguc, tay phai keo phdn bung -> mdt sd ngi quan (cd tinh hoan) bung ra.
+ Tdch va dua tinh hoan len lam kinh, nhd len vai gigt nudc cdt.
+ Nhd vai gigt ocxein axetic len tinh hoan dd nhugm mdu tir 15 - 20 phiit.
+ Day lamen, diing ngdn tay dn nhe len lammen -> td bao dan ddu lam va td bao va NST tung ra.
+ Dua tieu ban len kfnh di quan sat hinh thai, ddm sd lugng NST.
- Cdc nhdm tidn hanh lam tieu ban.
- Chii y cac thao tac phai nhe nhdng.
- Khi nhudm mau phai du thdi gian.
- Cac thanh vien trong nhdm ciing tham gia lam va quan sat dugc tieu ban de ve ra gidy.
- Dai dien cac nhdm trinh bay hoac cac nhdm quan sdt cheo cdc mdu ciia nhau.
Hogt dpng cua GV
* GV cdn luu y: Neu cd nhdm HS khdng quan sat dugc tieu ban thi cdn cho cac em biet li do cd the con chau chdu cdn non qua hoac thao tdc nhugm mau hay khau lam vd td bdo chua diing.
Hogt dpng cua HS
- HS: Ndu kdt qua chua dat cdn kiem tra lai thao tdc va quan sat mdu cua nhdm ban.
Hogt dpng 3
VlfeT BAO CAO THU HOACH
Muc tieu: HS bidt ghi chep lai nhirng ndi dung da hgc trong bai hgc.
MAU BAO CAO THU HOACH
STT 1 ,2
3
Dd'i tirdng NgUdi binh thudng Benh nhan bi Dao
Benh nhan bj TpcnP
So NST / te bao
46
47
45
Giai thfch cd che hinh thanh dot bien Binh thudng
Giao tif binh thudng (n) ket hpp vdi giao tii dot bie'n (n+1) tao thanh hpp tuf
2n+1 = 4 6 + 1 =47
Giao tif binh thudng (X) ket hpp vdi giao tCr dot bien (0) tao thanh hpp tirXO (44 + XO)
4. Nhan xet danh gia
- GV nhan xet gid hgc, danh gid kdt qua cua cac nhdm.
- GV can nhdc nhd nhdm cdn yeu vd thao tac va y thiic ki luat.
5. Dan do
- Hoan thdnh bao cao.
- On tap kidn thiic ve di truyen Menden.
ChiTdng II
TlNH QUY LUAT CUA HIEN TUONG Dl TRUYEN
• • ô
Bai 8