章节大纲

  • Close-up of corn on stalks in a field, highlighting the importance of seeds.

    Why are seeds important?
    ::为什么种子重要?

    Many important crops, such as corn, are planted and harvested as seeds. These seeds are important sources of food. For example, corn is ground into feed for chickens and cows. And corn syrup is used to sweeten beverages and candy. But most importantly, seeds are the starting point for a new plant.
    ::许多重要的作物,如玉米,都作为种子种植和收获,这些种子是重要的食物来源。例如,玉米是养鸡和奶牛的土壤。玉米糖浆也用于甜饮料和糖果。但最重要的是,种子是新植物的起点。

    Seeds and Seed Dispersal
    ::种子和种子分布

    Plants seem to grow wherever they can. How? Plants can't move on their own. So how does a plant start growing in a new area?
    ::植物似乎在它们能够生长的任何地方生长。怎么?植物不能自己移动。那么,一个植物如何开始在新的地区生长呢?

    What is a Seed?
    ::什么是种子?

    If you’ve ever seen a plant grow from a tiny seed, then you might realize that seeds are amazing structures. A seed is a plant ovule containing an embryo . The seed allows a plant embryo to survive droughts, harsh winters, and other conditions that would kill an adult plant. The tiny plant embryo can simply stay dormant , in a resting state, and wait for the perfect environment to begin to grow. In fact, some seeds can stay dormant for hundreds of years!
    ::如果你从小的种子中看到植物生长,那么你就会意识到种子是惊人的结构。 种子是含有胚胎的卵子。 种子允许植物胚胎在干旱、严寒的冬天和其他会杀死成年植物的条件中存活下来。 小型植物胚胎可以在休养状态中保持休眠,等待完美的环境开始生长。 事实上,有些种子可以保持休眠数百年!

    Another impressive feature of the seed is that it stores food for the young plant after it sprouts. This greatly increases the chances that the tiny plant will survive. So being able to produce a seed is a beneficial adaptation , and, as a result, have been very successful. Although the seedless plants were here on Earth first, today there are many more seed plants than seedless plants.
    ::种子的另一个令人印象深刻的特征是,种子在发芽后储存了年轻植物的食物。这大大增加了小植物存活的机会。因此,能够生产种子是一种有益的适应,因此非常成功。 尽管没有种子的植物首先存在于地球上,但今天的种子植物比没有种子的植物多得多。

    Learn more about seeds in the Seeds Massachusetts Institute of Technology video at  .
    ::在麻省理工学院的种子学院录像中,

    How are Seed Plants Successful?
    ::种子植物如何成功?

    For a seed plant to be successful, the seeds must be dispersed , or scattered around in various directions. If the seeds are spread out in many different areas, there is a better chance that some of the seeds will find the right conditions to grow. But how do seeds travel to places they have never been before? To aid with seed dispersal, some plants have evolved special features that help their seeds travel over long distances.
    ::种子植物要成功,种子必须分散,或分散在不同方向。 如果种子散布在许多不同地区,则某些种子更有可能找到合适的生长条件。 但种子如何去到从未到过的地方呢?为了帮助种子散布,一些植物已经发展出特殊特征,帮助种子长途繁殖。

    One such strategy is to allow the wind to carry the seeds. With special adaptations in the seeds, the seeds can be carried long distances by the wind. For example, you might have noticed how the "fluff" of a dandelion moves in the wind. Each piece of fluff carries a seed to a new location. If you look under the scales of pine cone, you will see tiny seeds with "wings" that allow these seeds to be carried away by the wind. Maple trees also have specialized fruits with wing-like parts that help seed dispersal ( Figure ).
    ::一种这样的策略就是让风吹起种子。 在种子中, 种子有特殊的适应性, 种子可以随风长途飘移。 比如, 您可能注意到了风中 dandelion 的 " fluflef" 是如何移动的。 每根长毛带种子到一个新的位置。 如果您在松锥的尺寸下看到, 您将会看到小种子, 上面有 " wicks " , 让这些种子被风吹走。 绿树上也有专门的果子, 上面也有有助于种子散布的翅膀一样的部件( Figure ) 。

    Maple seeds with wing-like structures important for wind dispersal.

    Maple trees have fruits with “wings” that help the wind disperse the seeds.
    ::芒树有果实和 " 翅膀 " ,帮助风吹散种子。

    Some flowering plants grow fleshy fruit that helps disperse their seeds. When eat the fruit, the seeds pass through an animal’s digestive tract unharmed. The seeds germinate after they are passed out with the animal's feces. Berries, citrus fruits, cherries, apples, and a variety of other types of fruits are all adapted to be attractive to animals, so the animals will eat them and disperse the seed ( Figure ). Some non-fleshy fruits are specially adapted for animals to carry them on their fur. You might have returned from a walk in the woods to find burrs stuck to your socks. These burrs are actually specialized fruits designed to carry seeds to a new location.
    ::一些花生植物种植有助于驱散种子的果实。当吃果实时,种子通过动物的消化道而不受伤害。种子随着动物的粪便而消散后发芽。 樱桃、柑橘、樱桃、苹果和其他种类的水果都经过了改造,以吸引动物,因此动物会吃掉它们并散布种子(图 ) 。 一些非易碎的果实特别适合动物携带它们的毛皮。 你也许已经从树林中步行回来,找到粘在袜子上的勃伦斯。 这些布丁实际上是专门设计用来将种子运到新地点的专门水果。

    A vibrant array of fruits in various colors and types displayed in a market.

    Fleshy fruits aid in seed dispersal, since animals eat the fruits and carry the seeds to a new location.
    ::易碎水果有助于种子散布,因为动物吃水果,把种子带到新的地点。

    Summary
    ::摘要

    • The seed contains a dormant embryo and stored food.
      ::种子含有休眠胚胎和储存的食物。
    • Fruits are adapted to disperse seeds with the help of animals or the wind.
      ::水果经过改造,在动物或风的帮助下撒撒种子。

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    • Fruit and Seed Dispersal at (6:08)
      ::水果和种子在6:08时分散
    1. What are four mechanisms of seed and fruit dispersal?
      ::种子和水果散布的四种机制是什么?
    2. What is the difference between a true fruit and a false fruit? Give an example of each.
      ::真实的果实和假的果实之间有什么区别呢?你们各拿一个譬喻来。
    3. List three ways that animals disperse fruit and seeds?
      ::列出动物散布水果和种子的三种方式?
    4. What causes the "explosion" for the explosive dispersal of seeds?
      ::是什么导致种子爆炸散布的“爆炸”?

    Review
    ::回顾

    1. What is a seed?
      ::什么是种子?
    2. Why was the evolution of the seed so beneficial to plants?
      ::为什么种子的进化对植物如此有益?
    3. Why is the vast dispersal of seeds beneficial to plants?
      ::为什么种子的大规模散布对植物有益?
    4. What are two ways that fruits are adapted to disperse seeds?
      ::水果有什么两种方法可以用来散播种子?