ndng do cac chat khf
CO2, Ga giCfa mao. mach phe nang din den sU khuech tan cCia cac chat khf.
Hoat dpng cua GV - GV dua cau hdi thao
luan:
+ Su trao ddi khi d dpng vat can da ndi len didu gi v^ sir tien hoa cua sinh gidi?
Hoqt dpng cua HS
- HS sit dung kieii thiic
trong phieu hpc tap ket hop vdi cac thdng tin GV cung
Hoqt dpng cua GV
f
- GV dd ldp ciing thao luan
dd giai dap thac mdc cua nhau.
- GV danh gia va bd sung kidn thlie:
+ 6 cdc loai chim, do thich nghi vdi ddi sdng bay luon nen cd nhieu he co quan cS^u tao dac bipt de giam trong lupng va dam bao cung cap du O2 khi bay.
Hoqt ddng cua HS dp.
- Thao luan nhdm thdng nha't y kien tra Idi:
+ Trong qua trinh phat trien, dpng vat da di chuydn tir m6i trudng nudc len can. + De thfch nghi cao dp vdi moi trudng sdng, dpng vat da hoan thien cd quan hd hap v^ hoat dpng hd hap. - HS cd th^ hdi:
Tai sao cac dpng vat d can nhu thd, ngudi khfing cd tui khi nhu d cac loai chim dd khi trao ddi khi duoc lien tuc va khdng cd lupng khi dpng trong phdi?
- Cd thd HS se dua ra nhieu y kien khac nhau:
+ Chi cd cac loai chim bay
cao, bay xa dn cd lupng
khi O2 Idn. + Ldp chim chua co co hoanh. Npi dung • - - 173
Hoqt dpng cua GV
+ Phdi chim nhd va xdp kh6ng dam bao cho su trao ddi khi.
+ Cac tui khi la ndi du trG khi, giam khdi lupng rieng ciia CO thd.
+ d cac loai chim bay lupng nhipt thai ra rat Idn.
Hoqt dpng cua HS Ndi dung
Hoqt ddng 2: Tim hieu vai trd cua mau va dich mo trong su vkn chuyen 6x1
va cacbonic trong ca thd va su trao ddi khi d te bao Muc tieu: ,
- HS tha^y duoc vai trd cua mau va dich md trong su van chuyen O2 va COj. - HS bie't hp thdng kien thiic dudi dang so dd.
- HS nam duac ca chd didu hoa hd ha'p.
Hoqt dpng cua GV - GV yeu du HS.
+ Nghien ciiu thdng tuj tranh hinh SGK.
+ Tdm tat so dd van chuen khi Uong CO thd.
- GV nhan xet danh gia va thdng bao dap an diing.
/- - • • , Hoqt dpng cua HS - HS nghien ciiu SGK trang 69. - Trao ddi nhdm.
- Thdng nhit y kidn, lap so
dd.
- Dai dipn cdc nhdm len bang vigt so dd, ldp nhan xet bd sung.
- Cac nhdm tu sira chiia
(ne'u dn). Npi dung r\ Coq ^ 2 • uan hdh^p
(ma ig phdi) CO2 -
i
Te'bao
- GV cho HS quan sat Uanh: trung khu didu hoa ho ha'p va so dd didu hda
ciir dpng he h^p. Yeu dn
HS tra Idi cau hdi: hoat dpng hd hap dupe dieu hoa bang CO che nao?
- GV nhan xet danh gia va
yeu cin HS khai quat ki^n
thiic.
- HS quan sat so dd, van dung ki€n thirc sinh hpc Idp dudi dd tra Idi.
+ Didu hoa bang thin kinh. + Dieu hoa bang thd dich.
- 6xi do CO thd la^y vao hay cacbonic do te bao thai ra duoc van chudn trong co thd nhd mau va dich md dudi dang hoa tan hoac ke't hpp vdi hemdglobin (Hb) Hb + Hb + 0 2 ^ H b 0 2 ^ khdng bin O2 + Hb + CO2 -> HbCo2 b6n * Hoat dpng hd hSp duoc didu hoa bang cd che t h ^ kinh va the dich.
* Ke't luan chung: HS dpc ke't luan cud'i bai SGK ttang 69.