khdng khi di qua be mat trao ddi khi (mang, phdi).
- Ca che' trao ddi khi ngoai va trao ddi khi d te' bao.
- Chu trpng tinh uu viet trong co ch6' trao ddi khi d ca va chim so vdi dpng vat khac. vat khac.
3. Bai mdi Md bai: Md bai:
- GV hdi: hd hsfp cd y nghia nhu the' nao ddi vdi ddi sdng dpng vat? - Dua vao cau tra Idi ciia HS, GV din dat vao bai mdi. - Dua vao cau tra Idi ciia HS, GV din dat vao bai mdi.
Hoqt dpng 1: Su trao ddi khi giiifa co the vdi moi trudng d cac nhdm dpngvat
Muc tieu: HS chi ra dugc boat dpng hd ha'p d cac nhdm ddng vat tii dan gian de'n phiic tap, nhdm dpngvat sdng d mdi trudng nudc va dpng vat d can. de'n phiic tap, nhdm dpngvat sdng d mdi trudng nudc va dpng vat d can.
Hoqt dpng cua GV - GV cho HS quan sat
tranh co quan hP hap d cac nhdm dpng vat, neu cd di^u kipn cho HS xem bang hinh ve hoat dpng hd ha'p eiia ea, sau bg, chim. ngudi.
- GV hoi: su trao ddi khi d cac nhdm ddng vat khac nhau vi sao?
Hoqt dpng cua HS
- HS quan sat tranh theo
doi phim, kgt vdi SGK
Hoqt dpng cua GV Hoat ddng cua HS
- GV dan dat; hoat dpng
he h^p khac nhau d cac nhdm dpng vat the hipn nhu the nao?
- GV da.t vSn de: d nhiing dpng vat bac thSp khPng cd CO quan h6 h^p thi su trao ddi khi dugc thuc hipn nhu the nko? Uiy vi du minh hoa.
- GV nhan xet danh gia va bd sung ki^n thiie (muc thdng tin bd sung phdn II).
- GV yeu cin HS:
+ Quan sat Uanh hinh SGK
trang 66 va ket hgp vdi kieh thiic idp dudi tra Idi dugc:
+ Do to chiic CO thd dpng vat khac nhau.
+ M6i trudng sd'ng khae nhau
- HS quan- sat hmh 17.1, ket hgp vdi eac kieh thiic sinh hpc ldp 7 vd dpng vat khOng xuong sd'ng dd tra Idi.
+ Rupt khoang hd hSip true tiep.
+ Giun da't ho h^p thuc hien nhd xoang co the. - Dai dipn HS trinh bay ddp an -^ ldp nhan x^t bd sung.
Npi dung
- HS nghien ciiu ddc lap vdi
SGK d^ thu thap thdng tin.
1. Su trao ddi khi qua be mat CO the mat CO the
- Dpng vat don bao va dpng vat da bao bac thap
chua ed ca quan hd hip
chuyen bipt.
- Su trao ddi khi dugc thuc hipn true tie'p qua mang t^
bao hoac hi mat ca the' nhd
su khuech tan, dxi tir mdi trudng vao co thd va cacbonic tir ca thd ra mdi trudng.
2. Sir trao ddi khi qua mang mang
Hoqt dpng cua GV
uang 66 muc 2.
+ Hoan thanh cac npi dung cua phie'u hpc tap sd 1 - GV cd the chieu mdt vai phi^u hgc tap ciaa nhdm de ldp cilng thao luan.
- GV nhan xet danh gia va bd sung kie'n thdc cho hoan thipn.
Hoqt ddng cua HS - Thao luan nhdm thdng
nhit y ki^n va ghi phieu hgc tap
- Dai dipn nhdm trinh bay dap an, ldp theo doi bd sung.
Ndi dung
Dap an phi^u hpc tap sd 1
OAP AN PHIEU HOC TAP SO 1
Npi dung - Co quan thUc hien - Ciif dpng ho hap -Hoat dpng trao ddi khf
Trao doi khi cua dpng vat d nudc - Mang gdi^:
+ Cac la mang bam vao cung mang, phia ngoai la nap mang. + He thdng mao mach d cac !a mang.
- Ha mieng ddng thdi md nap mang de htit nudc vao.
- Ngam mieng lai va khep mang tCr tCr nham thu hep khoang trdng day nude trao ra qua khe nap mang ra ngoai.
- O xi hoa tan trong nudc khue'ch tan vao mau, cacbonic khuech tan tif mau vao dong nudc chay.
- SUtrao ddi khi dien ra khi dong nudc ep chay qua cac khe nap mang ngugc chieu vdi ddng mau chay trong mao mach cOa mang.
- Thdi gian tiep xuc giCra dong nUdc va mao mach rat it nhUng qua trinh trao ddi chat dien ra thuan Igi.
Hoqt dpng cua GV Hoqt dpng cua HS
- HS cd thd hdi: nhiing loai
ca sdng sau dudi day bun hd hap nhu the^ nao?
- 6 loai ca map khong cd
Hoqt dpng cua GV
~"GV dd HS thao luan tu Ua Idi cau hdi.
- GV nhan xet va bd sung kien thiic.
+ Nhiing loai ca sdng d nudc ngheo dxi, diing bong
bong di tich luy mpt sd
lugng nhd' khdng khi khi ndi len mat nudc. Mau chay qua bong bdng se Uao ddi khi vdi khdng khi trong dd.
- GV yeu dn HS quan %it
tranhhinhl7.3,17.4,17.5. + Hoan thanh ndi dung phieu hpc tap sd 2: "Tim hidu hd ha'p d cae dpng vat can".
- GV nhan xet va danh gia ket qua hoat ddng ciia cae nhdm (Co the cho diem). - GV dua ra dap an dung uen man hinh -> cac nhdm chua.
Hoqt dpng cua HS
nap mang thi cir dpng hd ha'p xay ra nhu the nao?
Npi dung
- Ca nhan thu thap kieh
thlie tir tranh hinh va SGK trang 69.
- Trao ddi nhdm thdng nha't y kien -> ghi phieu hpc tap.
- Dai dipn nhdm trinh bay (tren khd giSy Ao).
- Ldp thao luan chung.
- Cac nhdm so sanh vdi dap an diing de tir danh gia lai ket qua cua minh va sira chiia bd sung.
3. Su trao ddi khi d cac dpng vat tren can dpng vat tren can
Npi dung trong phieu hpc tap sd 2.
DAP AN PHie'u HOC TAP SO 2 * Cd quan thuc hipn * C i i dpng hd ha'p Hoat dpng trao ddi khf
Trao ddi khi 6 sau bo