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七年级（上）《生态系统》（英文）
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七年级（上）《生态系统》（英文）
义务教育课程标准实验教科书七年级上册生物学一、.msyndlrp,gYvwIwhat else do you know about ecosystem?metsysocefomrofehT.sknurteohmfcigladTwpb32'N二、.sresopmocedsatcayeht,esopmocedydobtnalpdnaydoblaminaekamnacignufdnaairetcab;sremusnocsatcayehtos,yltceridniroyltceridstnalpnodeefylnonacyehT.sevlesmehtdnuopmoccinagroecudorpt'nacslamina;srecudorpsatcayehtos,ydobehtnitievreserdnasisehtnysotohpybdnuopmoccinagroekamstnalpneerg,metsysoceehtnI.metsyocfnphraig-,wOdklAbewdoofdnaniahcdooF.sremunocgalwdptbifh,yA For example, grass, hare, fox and wolf can be called a food chain. 三、)(kvOfoxowlsnakeharemouseeating-insect birdfrogspiderinsect on grassgrass?nepahliwgctWuoms'rfdk,I.2yDH1sucid There are nine pieces of food chains altogether, there are some relations among them. In theory, if the mount of the snakes reduces in the gross, the mount of the owls will also reduce, the amount of frog and rat will increase. The amount Of all kinds of organism will change relevantly. .bewdofamrnhtckliyTsp Ex 3. Please write down the names of food that you took yesterday, then write the places where they come from separately. To animals, please write their food, Don't forget to write down your names. Then use arrowheads to connect them together, what will you find out?四、Ecosystem has some ability to reculate.redonistamlcfhw,yuxpgOwill the amount of hare increase unlimitedly? Of course not. When the amount of hare increases, food will lack. Because it is short of food, the amount of hare will reduce, grass will also overgrow because of lack of hare. So on and on, The amount of hare will not increase unlimitedly.It also shows that ecosystem has a certain ability to self-regulate.The grassland is the same, why the grassland will change if people feed their flocks and herds excessively?Grassland will be destroyed, grass can't come out, at last it turn into a huge desert. What does the example make out?It shows that once grassland is used excessively, it will go beyond the range of self-regulation, it will bring negative effect.If the fish with a lot of piled toxicant is taken by people, what aftereffect will come out?Why do the organism which has more nutrition in food chain has more piled toxicant in its body? Now let's look at a picture( Page 26 some data analysis)analyze and discuss:
义务教育课程标准实验教科书七年级上册生物学一、.msyndlrp,gYvwIwhat else do you know about ecosystem?metsysocefomrofehT.sknurteohmfcigladTwpb32'N二、.sresopmocedsatcayeht,esopmocedydobtnalpdnaydoblaminaekamnacignufdnaairetcab;sremusnocsatcayehtos,yltceridniroyltceridstnalpnodeefylnonacyehT.sevlesmehtdnuopmoccinagroecudorpt'nacslamina;srecudorpsatcayehtos,ydobehtnitievreserdnasisehtnysotohpybdnuopmoccinagroekamstnalpneerg,metsysoceehtnI.metsyocfnphraig-,wOdklAbewdoofdnaniahcdooF.sremunocgalwdptbifh,yA For example, grass, hare, fox and wolf can be called a food chain. 三、)(kvOfoxowlsnakeharemouseeating-insect birdfrogspiderinsect on grassgrass?nepahliwgctWuoms'rfdk,I.2yDH1sucid There are nine pieces of food chains altogether, there are some relations among them. In theory, if the mount of the snakes reduces in the gross, the mount of the owls will also reduce, the amount of frog and rat will increase. The amount Of all kinds of organism will change relevantly. .bewdofamrnhtckliyTsp Ex 3. Please write down the names of food that you took yesterday, then write the places where they come from separately. To animals, please write their food, Don't forget to write down your names. Then use arrowheads to connect them together, what will you find out?四、Ecosystem has some ability to reculate.redonistamlcfhw,yuxpgOwill the amount of hare increase unlimitedly? Of course not. When the amount of hare increases, food will lack. Because it is short of food, the amount of hare will reduce, grass will also overgrow because of lack of hare. So on and on, The amount of hare will not increase unlimitedly.It also shows that ecosystem has a certain ability to self-regulate.The grassland is the same, why the grassland will change if people feed their flocks and herds excessively?Grassland will be destroyed, grass can't come out, at last it turn into a huge desert. What does the example make out?It shows that once grassland is used excessively, it will go beyond the range of self-regulation, it will bring negative effect.If the fish with a lot of piled toxicant is taken by people, what aftereffect will come out?Why do the organism which has more nutrition in food chain has more piled toxicant in its body? Now let's look at a picture( Page 26 some data analysis)analyze and discuss: