植物简介

Lesson Objectives
::经验教训目标

• Describe plants, their needs, and their importance.
  ::描述植物,它们的需求和重要性。

• Describe the structure and function of roots, stems, and leaves.
  ::描述根、根和叶的结构和功能。

Lesson Vocabulary
::词汇表课程

• leaf
  ::叶叶叶

• plant
  ::发电厂

• root
  ::根根根

• stem
  ::树干

Introduction
::导言

It's Mom's birthday today. Tonight your father is having a party for her. Everyone is helping out, even you. The table needs to be set with dinnerware. Mom is making your father's favorite meal. You are helping by picking up your things and putting them away. You are almost finished when the doorbell rings. You run to the door to answer and there stands friends of your parents. They are here for the party.
::今天是妈妈的生日。今晚你爸爸为她开派对。 每个人都在帮她,甚至你。餐桌要装上餐具。妈妈正在做你父亲最喜欢的饭。你正在帮你拿东西,然后把它们放走。门铃响的时候,你几乎就快吃完了。你跑到门前去回答,有你父母的朋友。他们是来参加晚会的。

You notice one person holding cut flowers. Another person is holding a plant. Flowers and plants are a common gift in our society. You are thinking that you would rather have a video game. Why are flowers and plants so important to us? Sure, they look nice. Might there be some other reasons? Perhaps! 
::你注意到一个人拿着切花,另一个人拿着植物。花和植物是我们社会中常见的礼物。你认为你宁愿有一个电子游戏。为什么花和植物对我们如此重要?当然,它们看起来很好。还有别的原因吗?也许吧!

What Are Plants?
::植物是什么? 植物吗?

Plants  are not like animals. Plants cannot move to find food. Instead, they must have the ability to survive where they are. They also must have the ability to make their own food. They also cannot move around to find a mate, so they have evolved unique ways to reproduce. 
::植物不像动物。植物不能移动去寻找食物。 相反,它们必须有能力生存。它们还必须有能力制造自己的食物。它们也不能四处移动去寻找伴侣,因此它们有独特的繁殖方式。

Needs of Plants
::植物需要

Plants are somewhat limited by temperature in terms of where they can grow. They need temperatures above freezing. They can survive temperatures below freezing, but cannot grow during this period of time. They also need light, carbon dioxide, and water. These are the ingredients they need to make their own food. Like most other living things, plants need oxygen. Oxygen is required for cellular respiration. In addition, plants need minerals. The minerals are required to make proteins and other organic molecules.
::植物生长的温度有一定的限制。 它们需要温度高于冰的温度。 它们可以在冰下生存下来, 但在这段时期内无法生长。 它们也需要光、 二氧化碳和水。 这些是它们制造自己食物所需的成分。 和其他生物一样, 植物需要氧。 细胞呼吸需要氧。 此外, 植物需要矿物。 矿物需要制造蛋白质和其他有机分子。

Importance of Plants
::植物的重要性

Life as we know it would not be possible without plants. Why are plants so important?
::我们知道,没有植物,生命是不可能实现的。 为什么植物如此重要?

• Plants supply food to nearly all land organisms, including people. We mainly eat either plants or other living things that eat plants.
  ::植物供应食物给几乎所有的陆地生物,包括人,我们主要吃植物或其他吃植物的活物。

• Plants produce oxygen. Oxygen is needed by almost all the Earth's organisms.
  ::植物产生氧气 几乎所有地球生物都需要氧气

• Plants absorb carbon dioxide from the air. This helps control the greenhouse effect and global warming.
  ::植物吸收空气中的二氧化碳,这有助于控制温室效应和全球升温。

• Plants recycle matter in ecosystems. For example, they are an important part of the water cycle. They take up liquid water from the soil through their roots. They release water vapor to the air from their leaves. 
  ::植物在生态系统中循环利用物质,例如,植物是水循环的一个重要部分,它们从土壤中通过根部吸收液态水,从叶子中释放水蒸气到空气中。

• Plants provide many products for human use. They include timber, medicines, dyes, oils, and rubber.
  ::植物提供许多供人使用的产品,包括木材、药品、染料、油料和橡胶。

• Plants provide homes for many other living things. For example, a single tree may provide food and shelter to many species of animals. One example is  Figure    of a bird's nest.
  ::植物为许多其他生物提供家园,例如,一棵树可以为许多动物提供食物和栖身之所,鸟类巢图就是一个例子。

Plant Structures
::工厂结构

Most modern plants have several structures that help them survive and reproduce. Major structures of most plants include roots, stems, and leaves. 
::大多数现代植物有几种结构来帮助他们生存和繁殖。 大多数植物的主要结构包括根、根和叶。

Roots
::根根

Roots  are important organs in most modern plants. There are two types of roots. First, there are the primary roots, which grow downward. Secondly, there are the secondary roots. These roots branch out to the sides. Together, all the roots of a plant make up the plant's root system.  Figure    shows two different types of plant root systems. A taproot system has a very long primary root, called a taproot. A fibrous root system has many smaller roots and no large, primary root.
::根是大多数现代植物的重要器官。 根有两种类型的根。 首先, 根是主要根, 向下发展。 其次, 根是第二根。 这些根分向两侧。 植物的所有根共同组成植物根系。 图显示植物根系的两种不同类型。 根根系统有很长的根根, 叫做根根。 根根根系统有许多小根, 没有大的根根。

The roots of plants have three major jobs. They must absorb water and minerals, anchor and support the plant, and store food.
::植物的根部有三大工作,它们必须吸收水和矿物质,固定和支撑植物,储存食物。

• Roots have special features that are well suited to absorb water and dissolved minerals from the soil.
  ::根有特别的特点,非常适合吸收土壤中的水和溶解矿物。

• Root systems help anchor plants to the ground. They allow plants to grow tall without falling over. 
  ::根系统能把植物固定在地上 它们能让植物长高而不会掉落

• In many plants, roots store food produced by the leaves. This process is called photosynthesis.
  ::在许多植物中,树根储存着叶子生产的食物,这个过程被称为光合作用。

Stems
::Stems Stems Stems Stems Stems Stems Stems Stems Stems Stems Stems Stems Stems 斯丁

Stems  are organs that hold plants upright. They allow plants to get the sunlight and air they need. Stems also bear leaves, flowers, cones, and smaller stems. These structures grow at points called nodes. The stem between nodes is called an internode. (See  Figure   .)
::丝质是保持植物直立的器官。 它们允许植物获得它们所需要的阳光和空气。 丝质还生着叶子、 鲜花、 锥子和小茎。 这些结构在被称为节点的地方生长。 节点之间的干点被称为内线。 (见图 。 )

Stems are needed for transport and storage. They carry water and minerals from roots to leaves. It carries dissolved sugar from the leaves to the rest of the plant. The stem is like an elevator for the plant. The stem allows movement from the top of the plant to the bottom and vice versa. Without this connection between roots and leaves, plants could not survive. In many plants, stems also stores food or water during cold or dry seasons.
::轮胎是运输和储存所需要的,从根到叶,将水和矿物质从根到叶,将溶解糖从叶到植物的其余部分,将溶解糖从叶子运到植物的其余部分,干料就像植物的电梯一样,干料可以从植物顶部转移到底部,反之亦然。没有根和叶之间的这种联系,植物就无法生存。在许多植物中,植物在寒季或旱季也储存着食物或水。

Leaves
::休假请请假

Leaves  are the keys not only to plant life but to virtually all life on land. The primary role of leaves is to collect sunlight. This sunlight is needed for the plant to make food. Leaves vary in size, shape, and how they are arranged on stems. You can see examples of different types of leaves in  Figure   .
::叶子不仅是植物生命的关键,而且也是几乎所有陆地生命的关键。叶子的主要作用是收集阳光。这种阳光是植物制造食物所必需的。叶子大小、形状和花茎的排列方式各不相同。您可以看到图中不同种类叶子的例子。

Each type of leaf is well suited for the plant's environment. It maximizes light exposure while conserving water. They are also reduces wind resistance. Leaves also benefit the plant in some other way in its particular habitat. For example, some leaves are divided into many smaller leaflets. This reduces wind resistance and water loss.
::每种叶叶都非常适合植物的环境,在节水的同时最大限度地增加光接触,还减少风阻力,在特定生境中以某种方式使植物受益,例如,有些叶片分成许多较小的传单,这样可以减少风阻力和水流失。

Leaves are basically factories for photosynthesis.
::叶子基本上是光合作用工厂

• A factory has specialized machines to produce a product. In a leaf, the "machines" are the chloroplasts.
  ::工厂有专门生产产品的机器,在叶子中,“机器”是叶板。

• A factory is connected to a transportation system that supplies it with raw materials and carries away the finished product. In a leaf, transport is carried out by veins containing vascular tissue. Veins carry water and minerals to the cells of leaves. They carry away dissolved sugar.
  ::工厂与一个运输系统相连,该运输系统供应原材料,运输成品,在叶子中,运输由含有血管组织的静脉进行,水和矿物质输送到叶子细胞,将溶解糖运走。

• A factory has bricks, siding, or other external protection. A leaf is covered with dermal cells. They secrete waxy cuticle to prevent evaporation of water from the leaf.
  ::工厂有砖块、护堤或其他外部保护,叶子被皮肤细胞所覆盖,它们密藏着蜡性切片,以防止叶子中的水蒸发。

• A factory has doors and windows to let some materials enter and leave. The surface of the leaf has tiny pores called stomata (stoma, singular). They can open and close to control the movement of gases between the leaves and the air. You can see a close-up of a stoma in  Figure   .
  ::工厂有门窗可以让某些材料进出。叶子表面有微小的孔孔,叫做stomata(单数,单数 ) 。 它们可以打开并接近控制叶子和空气之间的气体移动。 您可以在图中看到气态的缝合 。

What is Photosynthesis?
::什么是光合作用?

If a plant gets hungry, it cannot walk to a local restaurant and buy a slice of pizza. So, how does a plant get the "food" it needs to survive? Plants are  producers , which means they are able to make, or produce, their own "food." They also produce the "food" for other organisms. Plants collect the   from the   and turn it into special chemicals. Using the energy from the sun, they produce the special chemicals using air, water and nutrients from the soil. So once again, how does a plant get the food it needs to survive? The plants is able to make its own "food" from the  's  , carbon dioxide from the air, and  . 
::如果植物挨饿,它不能步行到当地餐馆买一块比萨饼。那么,植物如何得到它生存所需的“食物”?植物是生产者,这意味着它们能够制造或生产自己的“食物”。它们也为其他有机体生产“食物”。植物从中收集食物,把它变成特殊的化学物质。利用太阳的能量,它们利用土壤中的空气、水和养分生产特殊化学物质。再次,植物如何获得它生存所需的食物?植物能够从空气中制造自己的“食物 ” , 从空气中制造二氧化碳 。

Actually, almost all organisms obtain their energy from plants. For example, if a bird eats a caterpillar, then the bird gets the energy that the caterpillar. The caterpillar gets its energy from the plants it eats. So the bird indirectly gets energy from the plant. Therefore, the process of photosynthesis is central to sustaining life on Earth. 
::事实上,几乎所有生物都从植物中获得能量。例如,如果鸟食用毛虫,那么鸟就能得到毛虫的能量。毛虫从植物获得能量。所以鸟间接地从植物获得能量。因此,光合作用的过程对于维持地球上的生命至关重要。

Lesson Summary
::经验教训摘要

• Plants feed most other organisms. They also perform many other services.
  ::植物喂养大多数其他生物,还提供许多其他服务。

• Three organs (structures) commonly found in modern plants are roots, stems, and leaves.
  ::现代植物中常见的三种器官(结构)是根、根和叶。

Lesson Review Questions
::经验回顾问题

Recall
::回顾

1. What are plants? What do plants need?
   ::什么是植物 植物需要什么

1. How do plants grow?
   ::植物是如何生长的?

1. Outline the general life cycle of a plant.
   ::概述植物的一般生命周期。

Apply Concepts
::应用概念

4. Choose one of the three main organs of plants: roots, stems, or leaves. State the primary function of the organ, and then explain how the organ's structure suits it for its function.
   ::选择植物的三个主要器官之一:根、根或叶。 说明该器官的主要功能,然后解释该器官的结构如何适合其功能。

Think Critically
::仔细仔细思考

6. Why would life as we know it be impossible without plants?
   ::为什么我们所知道的没有植物是不可能生存的呢?