+ Cac d'ng khf phan nhanh thanh dng khf nho nh^t ti^p xiic true tiep vdi td' b^o.
+ Ong khi thdng vdi ben ngoai nhdidthct. - Cijf dpng CO dan 6 ph^n bung.
- Cac khf vao va ra khdi Cd the bang each khdi Cd the bang each phat tan tir ndi cd ndng dp cao de'n ndi cd nong dp thap.
- Su trao ddi khf didn ra trUc tid'p giO'a khdng ra trUc tid'p giO'a khdng khf vdi te bao, md.
Trao do\ khi 6 chim
- Cac dng khf nam trong phdi, c6 he trong phdi, c6 he thdng mao mach. - He thdng tui khf.
- Co dan cOa cac tui khf. khf.
- Co dan cOa cac cd thd. thd.
- Co dan cOa cac cd thd. thd. qua cac dng khi d phdi didn ra lien tuc theo mpt chieu nhat djnh, dam bao khdng co khf dpng trong cac dng khf 6 phdi.
- Sir trao ddi khi dien ra theo 2 chu ki. ra theo 2 chu ki.
Trao doi khi 5 dpng vat can khac
- Phe nang trong phdi. phdi.
- Hd thdng mao mach. mach.
- Nang ha cCia them mieng (ludng c i ^ . mieng (ludng c i ^ . - Co dan cd thd thay ddi khoang thSn (bo sat).
- Co dan cd thd (cd gian sudn, cd hoanh), gian sudn, cd hoanh), thay ddi khoang nguc (ngudi va thO).
- Do su chenh lech
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