17 Food and Nutrition-Low

Food and Nutrition Written by Katherine Follett

《食物与营养》作者:凯瑟琳·福莱特

What Needs Food? All living things need energy. They need it to live, to do all the things they do each day, and to stay healthy. Living things get this energy from food. In this book, you will learn how plants and animals get food. You will also find out how living things use food for energy. Before reading on, think about how plants get food. Do they eat? Then think about how plants use food for energy.

什么需要食物?所有的生物都需要能量。 他们需要它来生活，来做他们每天做的所有事情，来保持健康。 生物从食物中获取能量。 在这本书中，你将学习植物和动物是如何获得食物的。 你还会发现生物是如何利用食物获取能量的。 在继续阅读之前，想想植物是如何获取食物的。 他们吃东西吗?然后想想植物是如何利用食物获取能量的。

How Do Plants Get Food? Plants and animals get the energy they need in different ways. Animals eat food. But plants don't eat. Plants make their own food through a process called photosynthesis. Plants don't get food from soil. During photosynthesis, plants make a simple kind of sugar. The sugar is their food. Green plants soak up light energy from the Sun and use it to make the sugar. Plants also use a gas in the air called carbon dioxide. Plants take in carbon dioxide through tiny holes on the bottoms of their leaves. Plants make food using sunlight, carbon dioxide, and water. It is true that soil does not provide plants with food. But soil does give plants water and minerals. Both of these things are soaked up through the roots. Water and minerals are important during photosynthesis. Study the diagram of a plant on page 6. It explains the steps of photosynthesis that take place inside green plants.

植物如何获取食物?植物和动物以不同的方式获得它们所需的能量。 动物吃食物。但是植物不吃东西。 植物通过光合作用制造自己的食物。 植物不从土壤中获取养分。 在光合作用过程中，植物产生一种简单的糖。 糖是它们的食物。绿色植物吸收来自太阳的光能，并用它来制造糖。 植物也利用空气中的一种叫做二氧化碳的气体。 植物通过叶子底部的小孔吸收二氧化碳。 植物利用阳光、二氧化碳和水来制造食物。 土壤不能为植物提供食物，这是事实。 但土壤确实能给植物提供水分和矿物质。 这两种物质都是通过根部吸收的。 水和矿物质在光合作用中很重要。 研究第六页上的植物图。 它解释了发生在绿色植物内部的光合作用步骤。

Photosynthesis in Green Plants 1 Roots take in water. The plant carries the water to the plant's cells. 2 The cells have a green material in them called chlorophyll. Chlorophyll captures the Sun's energy. 3 Leaves take in carbon dioxide from the air through tiny holes. 4 The leaf cells use the Sun's energy to break down the carbon dioxide and water. They turn the chemicals into a simple sugar. The sugar is the plant's food. 5 The plant uses some of the sugar. It stores the rest in its leaves, stem, roots, and other parts. 6 When plants make sugar, some oxygen gas is left over. The leaves give off the oxygen into the air through the tiny holes.

绿色植物的光合作用1根吸收水分。 植物将水输送到植物的细胞中。 细胞中有一种叫做叶绿素的绿色物质。 叶绿素捕获太阳的能量。 树叶通过小孔吸收空气中的二氧化碳。 叶子细胞利用太阳的能量分解二氧化碳和水。 他们把化学物质变成了一种简单的糖。 糖是植物的食物。 植物消耗了一些糖。 它把其余的储存在叶子、茎、根和其他部位。 当植物制造糖时，会留下一些氧气。 树叶通过小孔向空气中释放氧气。

In the formula below, the left side explains what plants use during photosynthesis. The right side explains what plants produce during photosynthesis. The arrow is like an equal sign. How Do Plants Use Food for Energy? After photosynthesis happens, the plant has sugar for food. The sugar contains energy. The plant stores some of this energy in its leaves, stem, roots, fruit, and other parts. It uses the rest of the energy to grow by making new cells. So how does the plant get energy from sugar? The plant breaks down the sugar using respiration. Respiration is the opposite of photosynthesis. During respiration, the plant takes in oxygen from the air. It mixes the oxygen with the sugar to get the energy it needs. Then the plant sends water vapor and carbon dioxide back into the air. The next formula explains what plants use (on the left) and what they produce (on the right) during respiration.

在下面的公式中，左边解释了植物在光合作用中使用的物质。 右边解释了植物在光合作用中产生的物质。 箭头就像一个等号。 植物如何利用食物获取能量? 光合作用发生后，植物有糖作为食物。 糖含有能量。 植物将一些能量储存在叶子、茎、根、果实和其他部位。 它利用剩余的能量来制造新细胞。 那么植物是如何从糖中获取能量的呢? 植物通过呼吸作用分解糖。 呼吸作用与光合作用相反。 在呼吸过程中，植物从空气中吸收氧气。 它将氧气和糖混合以获得所需的能量。 然后植物将水蒸气和二氧化碳释放到空气中。 下一个公式解释了植物在呼吸过程中使用什么(左边)和产生什么(右边)。

To review, plants make their own food during photosynthesis. Then they use the energy from that food during respiration. Photosynthesis happens in sunlight. But respiration can happen in either the dark or the light. All living things use respiration to get energy from food. But plants also use photosynthesis to make their own food. This chart compares photosynthesis and respiration. Photosynthesis Respiration produces food uses food stores energy releases energy uses water uses sugar glucose uses carbon dioxide uses oxygen produces sugar glucose produces water vapor produces oxygen produces carbon dioxide occurs in sunlight occurs in the dark or light used mainly by plants used by all living things Try This To prove that plants give off water, seal a bag over a few plant leaves for a few days. See what happens.

回顾一下，植物在光合作用中制造自己的食物。 然后它们在呼吸过程中利用食物中的能量。 光合作用发生在阳光下。 但是呼吸作用既可以在黑暗中发生，也可以在光明中发生。 所有生物都通过呼吸从食物中获取能量。 但植物也利用光合作用来制造自己的食物。 这张图表比较了光合作用和呼吸作用。 光合作用呼吸作用产生食物利用食物储存能量释放能量利用水利用糖葡萄糖利用二氧化碳利用氧气产生糖葡萄糖产生水蒸气产生氧气产生二氧化碳发生在阳光下发生在黑暗中或光中发生主要由植物使用所有生物都使用试试这个为了证明植物释放水，在一些植物叶子上密封一个袋子几天。 看看会发生什么。