书城外语英国学生科学读本
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第10章 一块腻子(油灰)(2)

6.In this little plant,if you have good eyes,you can see a small bud,which will one day grow up and form thestem of the young plant.You may also see a very little pointed thing,which willgrow down and form the root.

7.Thus we see that a bean-seed is a perfect little plant,having leaves,and a stem,and a root.In the next lesson,we shall learn howthe tall,strong plant grows from a single seed.

SUMMARY

Seeds are the little things from which plants and trees grow.The seed comes from the old plant.Apples and pears and all other kinds of fruit are seeds covered with a thick juicy coat.In some seeds we can see the small root and bud from which the new plant grows.

【中文阅读】

1.小朋友,你能告诉我,这些种子都叫什么名字吗?大家都知道橡子,橡子是橡树的种子。①大家也一定见过豌豆、大豆、玉米、小麦的种子,还见过好多好多别的种子。

2.苹果和梨,都是包着“外衣”的种子。小小的褐色种子,紧紧地挤在苹果的中间,周围是一层厚厚的白色外衣,味道又甜,汁水又多,可好吃了。②3.有这种外衣的种子,就叫“果实”。这就是小朋友们最喜欢吃的!他们都喜欢熟透的苹果,喜欢多汁的鸭梨。他们在果园里摘水果,一摘就是一整天呢!③4.咱们把大豆泡在热水里,泡上一个小时,看看是什么样子?把褐色的皮剥下来,就能看见种子里面有两瓣厚厚的白色东西。5.这两个东西,其实是两片非常厚的叶子,叫“子叶”。两片子叶的边缘中间,你会看见一棵特别小的草。④6.要是你眼神足够好,在这棵小草里面,你会看到一个小芽,这小芽以后会长大,变成一颗幼苗的茎。你还可能看到一个非常小的尖儿,这个尖儿以后会往下长,长成幼苗的根。

7.你瞧,大豆的种子,自己也是一棵小草,有叶子,有茎,有根!下一课,我们会学到,一颗小小的种子,是怎么长成那些高大的树和草的。

译注

①橡树在咱们中国,从辽宁省到广东省都有分布。

②这些包着“外衣”的种子,属于“被子植物门”,是植物界最高级的一门。跟它相对的是“裸子植物门”,是种子植物里面比较低级的一类,种子没有果皮,是裸露的。

③现在中国城市里的孩子们,这种直接从树上摘水果的机会可能不多了。如果有机会,到乡村去试一试吧!

④原文里的seed-leaves是子叶的通俗名称,它的学名叫cotyledon(s)。子叶是植物的“营养仓库”或者“营养中转站”,对幼苗最初的成长起着至关重要的作用。植物子叶的多少,还是分类的重要依据。“被子植物门”分为“单子叶植物纲”和“双子叶植物纲”,大豆属于“双子叶植物纲”“豆目”“蝶形花科”“大豆属”,是最重要的双子叶植物之一。

SEEDS

种子

earthservesmus?-tardly?-ingtouch?-es moistgrownflan?-nela-cross?ap-pear?forththem-selves?sau?-cerbot?-tlechest?-nut with?-erquick?-lydown?-wardsuntil?need?-ed1.Let us take another bean and plant it in a pot of earth,and leave it to grow there.If we keep the earth moist and warm,the bean will soon grow into a plant,and will put forth green leaves.

2.But as the plant grows,the two fat seed-leaves wither away and become thin and dry.

3.At first the good stuff in them serves as food for the young bean;but when its new leaves and its roots have grown big and strong,they themselves take food for the plant from the earth and fromthe air.The leaves take in air through many tiny holes which are on their under -sides.

The roots suck in water and other things

from the ground.

4.Would you like to see a plant grow up quickly from a seed?Then spread some mustard-seed on a piece of flannel,and keep the flannel moist with water in a saucer.It will only be a day or two beforeBEAN WITH SEED-LEAVESSHRIVELLED(枯萎的大豆带着子叶)the young plants spring up.They will grow best if you keep the saucer in a dark place.

5.Or,would you like to see an acorn grow into a little oak?Take the acorn out of its cup,and hang it,with the point downwards,from a piece of wood lying across the top of a glass or of a bottle with a wide neck.

6.Now pour water into the bottle until thewater just touches the tip of the acorn.Keep the bottle in a dark place for a few days,and the young shoots will soon appear.A little white root will grow down into the water,and a small stem with a few green leaves on it will rise up into the air.

7.You may do the same thing with a chestnut,and in that case also a pretty little tree will grow in a month or so from the seed.

8.More water should be poured into the glass as it is needed,so as to keep the water just touching the point of the acorn or the chestnut.

SUMMARY

Seeds need moist earth and warmth to grow.As the plant grows,the seed-leaves wither away.When the young plant has grown,its seeds and leaves get food for it from the earth and from the air.Some seeds will grow very quickly in water.An acorn or a chestnut allowed to touch water will grow up into a little tree in a short time.

【中文阅读】

1.咱们再拿一颗大豆种子,把它种在一个有土的花盆里,让它在那儿生长。要是能让土壤一直温暖潮湿,豆子很快就会长成一棵幼苗,长出绿色的叶子来。

2.可是,大豆在生长的时候,两片肥厚的子叶就会渐渐凋谢,变得干枯。

3.一开始,豆苗是从子叶中吸取养料的,但是豆苗的叶子和根长大了以后,就可以自己从土壤中、从空气中吸取养料了。叶子的下面有很多小孔,可以吸进空气。根从土地中吸收水,也吸收别的东西。①4.你想看见一颗种子很快长成一棵幼苗吗?那就把一点儿芥菜子洒到一块法兰绒布上,把绒布浸在一碟子水里面。只要一两天工夫,芥菜的幼苗就会长出来了!把碟子放在暗处,芥菜会长得最好。

5.还有,你想不想看见一颗橡子长成一棵小树?把橡子从杯子形状的硬壳里拿出来,尖儿朝下,系上一根细线吊起来,把细线的另一头拴在一根木棍上,把木棍放在一个玻璃杯上,或者广口瓶上。

6.然后往瓶子里倒水,直到水面刚刚碰到橡子下面的尖儿为止。把瓶子在暗处放上几天,橡子就会很快地发芽,让小小的白色的根伸到水里,让茎带着几片绿叶长到空中!

7.小朋友也可以这么种栗子,过上大概一个月,小小的栗子树就会从种子里长出来了。

8.要是杯子(瓶子)里的水少了,就要再往里倒水,让水面碰到橡子或者栗子的尖儿。

译注

①叶子最重要的作用是“光合作用”,利用叶绿素,在光的照射下,通过一系列复杂的反应,将二氧化碳和水变成有机物,当作自己的营养,并且释放出氧气。这是我们人类和一切动物生存的基础。

THE AIR WE BREATHE