D286【植物科学1】V-learn小西妈双语工程1907期112Eric21.4.12打卡

宝贝疙瘩蛋

3a-unit 3 Plants 拓展 part1
每年都会反复遇到植物主题，这次在复习的基础上再深入一点，侧重点放在光合作用，植物的分布和种子上面。
已掌握：Parts of plant, life cycle of plant
 What Does a Plant Need?
 What affects Plant Growth?Celery Stick Experiment
 What is Photosynthesis? 今日话题海报，整合了各种资源，帮助Eric对植物科学构建系统概念，理解并用自己的语言组织讲出来，分为以下4部分内容。说实话，这种讲解的形式尝试的不多，以前都是游戏中自然输出，但这种有逻辑的讲解，对Eric和我来说都是挑战，一开始的拘谨到后来的自high，一起加油吧。

P1: Parts of plant

P2: Life cycle of a plant P3: What plants need? P5: Photosythesis Experiment: How plants drink water? 这个实验以前用白菜、鲜花都做过，这次选择用芹菜再试一次，反正Eric喜欢这些奇怪的实验，哈哈。 一起提取叶绿素，观察叶片如何呼吸。

-------------------备课内容---------------------

(1) What Does a Plant Need?

A plant is a living thing. People need water, food and air to live. Plants also need certain things to live.
❤ Plants need air. We need part of the air called oxygen (O2). Plants use another part of the air called carbon dioxide (CO2). They take carbon dioxide from the air and release oxygen back into the environment.
❤ Plants need plenty of water. Their roots absorb water from the soil after it rains.
❤ Plants also use nutrients from the soil. They absorb the nutrients using their roots.

❤Plants need plenty of sunlight. Plants use sunlight to make their own food. They trap light from the sun using their leaves. This is called photosynthesis.

Q: What happens when plants get too much sun?
What happens when plants don't get enough water?
What things can cause a plant to not grow at all?
(2) How does a plant drink its water?
M: Eric, we are going to do an experiment to see how a plant drinks water.
E: Ok.
M: Good. We need some leaves, maybe celery or cabbage is a good choice, then we will cut it into two half.
E: Ok.
M: Then, please add the colored water into this cup. Good. Let's put the leaves in it and leave them overnight in order for the stalk to drink water.
M: Look Eric, the water has moved through the leaf and colored the plant!
E: Wow, the plant is all red now.

Experiment: Celery Stick Science

(3) What is Photosynthesis? 光合作用

“photo” which means light +“synthesis” which means putting together.

Photosynthesis is a process that plants use to breathe and to make food. They use the light from the sun, along with nutrients in the soil and a gas called CO2 to make sugar, which feeds the plant. During this process, O2 is released into the air.

How plants make their food?

1）Chlorophyll to soak up the sunshine

• All plants have a chemical in their leaves called chlorophyll /ˈklɔːrəfɪl/叶绿素.
• The chlorophyll is what makes the leaves of the plant green.
• But that is not the only job chlorophyll has.
• Its other job is to soak up the warmth and energy from the sun's rays.
• Sun-energy isn't all a plant needs to make its food, though. They also need water and air.

2) Drink up

• While the leaves are collecting energy from the sun, they are also pulling water up from the plant's roots.
• The water, which is in the soil, travels through the roots, up the stem and into the leaves…kind of like a big straw. But that's not all…
• Water enters the roots via a plant cell called xylem.
• One issues that most land plants have is drying out.
• But plant are very clever and have a specialized structure called stomata which will not allow carbon dioxide pass through its protective waxy layer covering the leaf (cuticle).

3) Take a deep breath

• Plants have to breathe just like you and I do.
• Plants take a deep breath, they breathe in carbon dioxide and when they let it out, it is oxygen.
• A plant's leaves also have hundreds of thousands of tiny holes in them called stomata气孔.
• The stomata are so small you have to have a microscope to see them, but they are big enough to breathe in the carbon dioxide a plant needs to make its food.
• Plants take in carbon dioxide through their leaves at the same time they are soaking up energy from the sun and taking a drink of water.

4) Dinner time

• When the carbon dioxide, water and energy from the sun are combined, the sun turns the water and carbon dioxide into glucose (sugar).
• The plant uses the glucose as food and takes hydrogen molecules from the water to keep itself from getting dry and wilted.