我很高興你提出問題：關於種子

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I’m Glad You Asked： The Seed

Of the many different structures produced by plants， one of the most remarkable is the seed。 At its most basic， the seed is a reproductive structure consisting of an embryonic plant enclosed in a protective covering， the seed coat。 But this simple definition hardly acknowledges all that the seed is and does。 Within the seed coat， we find the embryo and nutritional materials used to sustain the germinated seedling until it is able to make its own food via photosynthesis。 In flowering plants， the nutritional materials are composed of oils， fats， starches， and many other compounds including sugars， that are usually distributed in seeds in one of two ways。 Either the nutrients surround the embryo in a tissue known as endosperm， as in a corn seed， or the nutrients are stored in leaf-like structures known as a cotyledons which are part of the embryo， as in bean seeds。

在植物產生的許多不同結構中，最引人注目的之一是種子。 從最基本的角度來說，種子是一種生殖結構，由包裹在保護性覆蓋層（種皮）中的胚芽植物組成。 但是，這個簡單的定義幾乎不承認種子是過去和現在所做的一切。 在種皮中，我們發現了用於維持發芽幼苗直至能夠透過光合作用製成自己的食物的胚胎和營養物質。 在開花植物中，營養物質由油，脂肪，澱粉和許多其他化合物（包括糖）組成，通常以兩種方式之一分佈在種子中。 營養物質要麼在玉米胚芽組織中的胚芽周圍（如玉米種子中）圍繞胚芽，要麼將營養物儲存在稱為子葉的葉狀結構中（如豆子種子），胚芽是胚芽的一部分。

If the nutrition is stored as endosperm， the cotyledons are generally small and undeveloped； whereas when the cotyledons are enlarged， there is little endosperm in the mature seed。 Most of us are familiar with nutrient-containing cotyledons。 When you eat beans， peanuts or walnuts you are largely consuming cotyledons containing the stored nutrients。

如果將營養物作為胚乳儲存，則子葉通常很小且不發育； 當子葉擴大時，成熟種子中的胚乳很少。 我們大多數人都熟悉含營養的子葉。 當您吃豆類，花生或核桃時，您會大量食用含有所儲存營養成分的子葉。

On the other hand， the consumption and an understanding of what is nutrient-rich endosperm is less familiar to most of us。 But for those of us who eat corn， coconuts， or drink coconut milk， we are consuming endosperm； that is， nutrition meant to sustain the developing seedling。 When you bite into fresh corn you often are sprayed with liquid that is sweet and sticky； this is liquid endosperm and is comprised mainly of sugars。 But as the corn ear matures， the sweet liquid is converted to solid starch。 This is what happens when you buy “old” corn or corn that has not been refrigerated； the endosperm has been converted to starch and the corn kernels are no longer sweet。

另一方面，大多數人對食用和了解什麼是營養豐富的胚乳並不那麼熟悉。 但是對於那些吃玉米，椰子或喝椰子牛奶的人來說，我們使用的是胚乳。 也就是說，營養是指維持不斷髮育的幼苗。 當您咬進新鮮的玉米時，經常會噴出黏稠的甜味液體。 這是液態胚乳，主要由糖組成。 但是隨著玉米穗的成熟，甜味液體會轉化為固體澱粉。 當您購買“舊”玉米或未冷藏的玉米時，就會發生這種情況。 胚乳已轉化為澱粉，玉米粒不再甜。

Let’sconsiderendosperminalittlemoredetail。Nexttimeyouareintheproducesectionofyourfavoritemarkethaveacloselookatthecoconuts。Ifthecoconutisnotover-ripe，youwillbeabletoheartheliquidendospermsloshingaboutwhenyoushakethecoconut。

讓我們考慮一下更多細節。下一次您在最喜歡的市場的生產區域中仔細檢視椰子。如果椰子未完全成熟，則當您搖動椰子時，您可能會流失液體胚乳。

You’ll also notice that at one end of the coconut can be found three depressions， commonly called “eyes”。

您還會注意到，在椰子的一端可以發現三個凹陷，通常稱為“眼睛”。

Under each of these eyes is or was an embryo。 Each coconut， therefore， is a result of three separate fertilizations to produce a structure in which the three fertilized embryos are joined and united to form the coconut （the fruit containing the seed）。 However， in coconuts， at some point in fruit and seed development a decision is made to abort two of the three embryos and to channel the endosperm nutrients to a single embryo。 But under which eye is the retained embryo？ If you look carefully at the coconut you’ll notice ridges （sutures， highlighted below） which are evidence of the previous uniting of the original， three developing embryos。

在每隻眼睛下是或曾經是胚胎。 因此，每個椰子都是三個不同的受精過程的結果，產生了一種結構，在該結構中，三個受精的胚結合在一起並形成了椰子（含有種子的果實）。 但是，在椰子中，在果實和種子發育的某個時刻，決定終止三個胚中的兩個，並將胚乳營養物質輸送到單個胚中。 但是保留的胚胎在哪隻眼下？ 如果仔細看一下椰子，您會注意到山脊（縫線，在下面突出顯示），這是先前原始的三個正在發育的胚胎結合在一起的證據。

You’ll also notice that the size of each of the three sections is different。 Under the eye associated with the largest section you will find the remaining， developing embryo。 So next time you eat a coconut， open it carefully and see if you can find the embryo （A） surrounded by solidified endosperm （B） and the hard shell （fruit wall = C）。 And remember to drink the nutrient-enriched liquid endosperm！

您還會注意到，這三個部分的大小均不同。 在與最大部分相關的眼睛下，您將找到剩餘的發育中的胚胎。 因此，下次您吃椰子時，請小心開啟它，看看是否能找到被凝固的胚乳（B）和硬殼（果壁= C）包圍的胚胎（A）。 並記住要喝富含營養的液態胚乳！