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Lesson 20 Snake poison蛇毒
First listen and then answer the following question. 聽錄音，然后回答以下問題。 What are the two different ways in which snake poison acts? How it came about that snakes manufactured poison is a mystery. Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced upon them by the survival competition; they could have caught and lived on prey without using poison, just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite. And why only snakes? Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits -- just a bite and no more effort needed. In fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders also why nature with some sankes conqued poison of such extreamy. In the conversion of saliva into poison, one might suppose that a fixed process took place. It did not; some snakes manufacture a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood. The makers of the nerve poison include the mambas and the cobras and their venom called neurotoxic. Vipers (adders) and rattlesnakes manufacture the blood poison, which is known as haemolytic. Both poisons are unpleasant, but by far the more unpleasant is the blood poison. It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. Be that as it may, the nerve poison does its business with man far more quickly than the blood poison. This, however, means nothing. Snakes did not acquire their poison for use against man but for use against prey such as rats and mice, and the effects on these of viperine poison is almost immediate.【參考譯文】 蛇是怎樣產生毒液的，這是一個謎。蛇的唾液本來和我們人的消化液一樣柔和，但經過漫長的時間，演變成了今天仍無法分析清楚的毒液。毒液不是生存競爭強加給它們的，它們也可以不用毒液捕捉動物而生存，就像今天成千上萬的無毒蛇那樣。毒液對毒蛇來說只不過是一種舒適生存的優(yōu)越手段，它使蛇不用費多大力氣就能捕獲到食物，輕咬一口即可。為什么只有蛇才有毒液呢？譬如說，如果貓有毒液，那對貓會大有幫助，它就不必再和又大又兇的老鼠邊跑邊博斗了，也不必再和大兔子扭斗了，只要咬一口，就不必再費大力氣。因此，任何食肉動物有了毒液，都能從中獲益。不過，當它們相互撕打時，毒液就成了利弊參半的武，可以殺死對方，也可以被對方的毒液殺死。然而，在脊椎動物中，大自然神秘模測地只選擇了蛇（還有一種蜥蜴），人們弄不清楚大自然為什么在某些蛇的身上調制出如此高效的毒液來。 人們可能認為，唾液轉變成毒液，其中有固定的程序。其實沒有。有些蛇產生的毒液也在各方面與另外一些毒蛇產生的毒液不同，就像砒霜不同于馬錢子堿一樣。不同毒蛇產生的毒液產生的效果不同，一種毒液作用于神經，另一種毒液作用于血液。 產生神經毒液的蛇有一種非洲樹眼鏡蛇和眼鏡蛇，它們的毒液稱為神經毒素。蝰蛇（蝮蛇）和響尾蛇產生血液毒素，稱為溶血性毒液。這兩種毒液都很可怕，但溶血性毒液尤其厲害。據(jù)說，神經毒液在兩種毒液中是較為原始的一種，而溶血性毒液，打個比方說，是根據(jù)改良配方生產的一種較新的產品。不過，神經毒辣液比溶血性毒液在人身上起作用快得多。但是，這沒有什么關系，因為蛇有毒液不是用來對付人的，而是對付它的獵物，諸如鼠類，毒液對這些獵物會立刻起作用。1.saliva n.唾液
2.digestive adj.助消化的 例句：This oil is very good for regulating digestive disorders. 這種油對消化不良很有療效。 3.defy v.使不可能 例句：His strange behaviour defies understanding. 他古怪的舉止使人難以理解。 4.analysis n.分析
5.prey n.被捕食的動物
6.fierce adj.兇猛的 例句：The house is guarded by a fierce dog. 這棟房子由一條兇犬看守。
7.tussle n.扭打 例句：I had a tussle to get the knife off him. 我與他扭打一陣才把刀子奪下。
8.carnivore n.食肉動物
9.vertebrate n.脊椎動物
10.lizard n.蜥蜴
11.concoct v.調制
12.potency n.效力 例句：The drug will lose its potency when exposed to moisture. 這藥一受潮就會失效。
13.conversion n.轉變
14.arsenic n.砒霜
15.strychnine n.馬錢子堿
16.mamba n.樹眼鏡蛇
17.cobra n.眼鏡蛇
18.venom n.毒液
19.neurotoxic adj. 毒害神經的
20.viper n.蝰蛇
21.adder n.蝮蛇
22.rattlesnake n.響尾蛇
23.haemolytic adj.溶血性的
24.viperine adj.毒蛇1.How it came about that snakes manufactured poison is a mystery. 參考翻譯：蛇是怎樣產生毒液的，這是一個謎。 講解：How it comes怎么會……相當于why,在口語中用的比較多。 2.it enables it to get its food with very little effort, no more effort than one bite. 參考翻譯：它使蛇不用費多大力氣就能捕獲到食物，輕咬一口即可。 講解：no more than, not more than no more than的意思是“只不過”，not more than的意思是“不多于”。試比較： There are no more than ten tickles left. 剩下不到十張票。 (有“票少”的含義) The experiment was done by not more than 5 persons. 做這個試驗的人不到五個。(沒有“多”或“少”的含義，只是客觀地說明數(shù)目) This room is no bigger than that. 這個房間并不比那個大。 (有“兩個房間都不大”的含義) This room is not bigger than that one.這個房間不比那個大。 (沒有“兩個房間都不大或都不小”的含義) [注]注意not …. Any more than或no more...than在下面句子中的用法。如： They cannot do the impossible any more than we can.他們和我們同樣不能做不可能的事情。 He is no more diligent than I am.他和我同樣不勤奮 no less than和not less than no less than的意思是“不亞于”，not less than的意思是“不少于”。試比較： There were no less than a thousand people at the meeting. 到會的有一千人之多。(有“到會人多”的含義) There were not less than one thousand people at the meeting. 到會的至少有一千人。(沒有“到會人多或人少”的含義) This song is no less popular than that one.這首歌之受歡迎不亞于那首歌。(有“兩首歌都受歡迎”的含義) This song is not less popular than that one.這首歌受歡迎的程度不比那首差。(純粹比較。不一定有“兩首歌都受歡迎”的含義) 3.Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits -- just a bite and no more effort needed. 參考翻譯：譬如說，如果貓有毒液，那對貓會大有幫助，它就不必再和又大又兇的老鼠邊跑邊博斗了，也不必再和大兔子扭斗了，只要咬一口，就不必再費大力氣。 講解：for instance例如，相當于for example 4.It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. 參考翻譯：It is said據(jù)說，it形式主語，避免頭重腳輕。 講解：the more primitive of the two兩者進行比較，兩者中較……的一個。如果是三者或三者以上比較，則可以用高級。1.How it came about that snakes manufactured poison is a mystery. 蛇是怎樣產生毒液的，這是一個謎。 2.Over the periods their saliva, a mild, digestive juice like our own,was converted into a poison that defies analysis even today. 蛇的唾液本來和我們人的消化液一樣柔和，但經過漫長的時間，演變成了今天仍無法分析清楚的毒液。 3.It was not forced upon them by the survival competition;they could have caught and lived on prey without using poison,just as the thousands of non-poisonous snakes still do. 毒液不是生存競爭強加給它們的，它們也可以不用毒液捕捉動物而生存，就像今天成千上萬的無毒蛇那樣。 4.One wonders saliva into why Nature, with respect from that of others, as other on the blood. 人們弄不清楚大自然為什么在某些蛇的身上調制出如此高效的毒液來。 5.some snakes manufacture a poison different in every respect from that of others,as different as arsenic is from strychnine. 有些蛇產生的毒液也在各方面與另外一些毒蛇產生的毒液不同，就像砒霜不同于馬錢子堿一樣
Lesson 20 Snake poison蛇毒
First listen and then answer the following question. 聽錄音，然后回答以下問題。 What are the two different ways in which snake poison acts? How it came about that snakes manufactured poison is a mystery. Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced upon them by the survival competition; they could have caught and lived on prey without using poison, just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite. And why only snakes? Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits -- just a bite and no more effort needed. In fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders also why nature with some sankes conqued poison of such extreamy. In the conversion of saliva into poison, one might suppose that a fixed process took place. It did not; some snakes manufacture a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood. The makers of the nerve poison include the mambas and the cobras and their venom called neurotoxic. Vipers (adders) and rattlesnakes manufacture the blood poison, which is known as haemolytic. Both poisons are unpleasant, but by far the more unpleasant is the blood poison. It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. Be that as it may, the nerve poison does its business with man far more quickly than the blood poison. This, however, means nothing. Snakes did not acquire their poison for use against man but for use against prey such as rats and mice, and the effects on these of viperine poison is almost immediate.【參考譯文】 蛇是怎樣產生毒液的，這是一個謎。蛇的唾液本來和我們人的消化液一樣柔和，但經過漫長的時間，演變成了今天仍無法分析清楚的毒液。毒液不是生存競爭強加給它們的，它們也可以不用毒液捕捉動物而生存，就像今天成千上萬的無毒蛇那樣。毒液對毒蛇來說只不過是一種舒適生存的優(yōu)越手段，它使蛇不用費多大力氣就能捕獲到食物，輕咬一口即可。為什么只有蛇才有毒液呢？譬如說，如果貓有毒液，那對貓會大有幫助，它就不必再和又大又兇的老鼠邊跑邊博斗了，也不必再和大兔子扭斗了，只要咬一口，就不必再費大力氣。因此，任何食肉動物有了毒液，都能從中獲益。不過，當它們相互撕打時，毒液就成了利弊參半的武，可以殺死對方，也可以被對方的毒液殺死。然而，在脊椎動物中，大自然神秘模測地只選擇了蛇（還有一種蜥蜴），人們弄不清楚大自然為什么在某些蛇的身上調制出如此高效的毒液來。 人們可能認為，唾液轉變成毒液，其中有固定的程序。其實沒有。有些蛇產生的毒液也在各方面與另外一些毒蛇產生的毒液不同，就像砒霜不同于馬錢子堿一樣。不同毒蛇產生的毒液產生的效果不同，一種毒液作用于神經，另一種毒液作用于血液。 產生神經毒液的蛇有一種非洲樹眼鏡蛇和眼鏡蛇，它們的毒液稱為神經毒素。蝰蛇（蝮蛇）和響尾蛇產生血液毒素，稱為溶血性毒液。這兩種毒液都很可怕，但溶血性毒液尤其厲害。據(jù)說，神經毒液在兩種毒液中是較為原始的一種，而溶血性毒液，打個比方說，是根據(jù)改良配方生產的一種較新的產品。不過，神經毒辣液比溶血性毒液在人身上起作用快得多。但是，這沒有什么關系，因為蛇有毒液不是用來對付人的，而是對付它的獵物，諸如鼠類，毒液對這些獵物會立刻起作用。1.saliva n.唾液
2.digestive adj.助消化的 例句：This oil is very good for regulating digestive disorders. 這種油對消化不良很有療效。 3.defy v.使不可能 例句：His strange behaviour defies understanding. 他古怪的舉止使人難以理解。 4.analysis n.分析
5.prey n.被捕食的動物
6.fierce adj.兇猛的 例句：The house is guarded by a fierce dog. 這棟房子由一條兇犬看守。
7.tussle n.扭打 例句：I had a tussle to get the knife off him. 我與他扭打一陣才把刀子奪下。
8.carnivore n.食肉動物
9.vertebrate n.脊椎動物
10.lizard n.蜥蜴
11.concoct v.調制
12.potency n.效力 例句：The drug will lose its potency when exposed to moisture. 這藥一受潮就會失效。
13.conversion n.轉變
14.arsenic n.砒霜
15.strychnine n.馬錢子堿
16.mamba n.樹眼鏡蛇
17.cobra n.眼鏡蛇
18.venom n.毒液
19.neurotoxic adj. 毒害神經的
20.viper n.蝰蛇
21.adder n.蝮蛇
22.rattlesnake n.響尾蛇
23.haemolytic adj.溶血性的
24.viperine adj.毒蛇1.How it came about that snakes manufactured poison is a mystery. 參考翻譯：蛇是怎樣產生毒液的，這是一個謎。 講解：How it comes怎么會……相當于why,在口語中用的比較多。 2.it enables it to get its food with very little effort, no more effort than one bite. 參考翻譯：它使蛇不用費多大力氣就能捕獲到食物，輕咬一口即可。 講解：no more than, not more than no more than的意思是“只不過”，not more than的意思是“不多于”。試比較： There are no more than ten tickles left. 剩下不到十張票。 (有“票少”的含義) The experiment was done by not more than 5 persons. 做這個試驗的人不到五個。(沒有“多”或“少”的含義，只是客觀地說明數(shù)目) This room is no bigger than that. 這個房間并不比那個大。 (有“兩個房間都不大”的含義) This room is not bigger than that one.這個房間不比那個大。 (沒有“兩個房間都不大或都不小”的含義) [注]注意not …. Any more than或no more...than在下面句子中的用法。如： They cannot do the impossible any more than we can.他們和我們同樣不能做不可能的事情。 He is no more diligent than I am.他和我同樣不勤奮 no less than和not less than no less than的意思是“不亞于”，not less than的意思是“不少于”。試比較： There were no less than a thousand people at the meeting. 到會的有一千人之多。(有“到會人多”的含義) There were not less than one thousand people at the meeting. 到會的至少有一千人。(沒有“到會人多或人少”的含義) This song is no less popular than that one.這首歌之受歡迎不亞于那首歌。(有“兩首歌都受歡迎”的含義) This song is not less popular than that one.這首歌受歡迎的程度不比那首差。(純粹比較。不一定有“兩首歌都受歡迎”的含義) 3.Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits -- just a bite and no more effort needed. 參考翻譯：譬如說，如果貓有毒液，那對貓會大有幫助，它就不必再和又大又兇的老鼠邊跑邊博斗了，也不必再和大兔子扭斗了，只要咬一口，就不必再費大力氣。 講解：for instance例如，相當于for example 4.It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. 參考翻譯：It is said據(jù)說，it形式主語，避免頭重腳輕。 講解：the more primitive of the two兩者進行比較，兩者中較……的一個。如果是三者或三者以上比較，則可以用高級。1.How it came about that snakes manufactured poison is a mystery. 蛇是怎樣產生毒液的，這是一個謎。 2.Over the periods their saliva, a mild, digestive juice like our own,was converted into a poison that defies analysis even today. 蛇的唾液本來和我們人的消化液一樣柔和，但經過漫長的時間，演變成了今天仍無法分析清楚的毒液。 3.It was not forced upon them by the survival competition;they could have caught and lived on prey without using poison,just as the thousands of non-poisonous snakes still do. 毒液不是生存競爭強加給它們的，它們也可以不用毒液捕捉動物而生存，就像今天成千上萬的無毒蛇那樣。 4.One wonders saliva into why Nature, with respect from that of others, as other on the blood. 人們弄不清楚大自然為什么在某些蛇的身上調制出如此高效的毒液來。 5.some snakes manufacture a poison different in every respect from that of others,as different as arsenic is from strychnine. 有些蛇產生的毒液也在各方面與另外一些毒蛇產生的毒液不同，就像砒霜不同于馬錢子堿一樣