This unit deals with the structures and functions of plant organs including roots, stems, leaves, and flowers. Students learn that a plant is sustained by the systematic functioning of all its organs. Students observe the roots, stems, leaves, flowers and fruits of a plant in order to understand the structures and functions of these plant organs. Students learn how to use a microscope.

The grade 5 English science unit, Plants, meets the academic content standards set in the Korean curriculum, which state students should:

a) Be able to observe the entire structure of a plant and identify a root, stem, leaf, flower and fruit.

b) Understand the structure of the root and its support, absorption and preservation functions.

c) Become aware of the outer appearance of the stem and its inner structures and understand that water absorbed by the roots runs through the stem to other organs.

d) Understand transpiration and photosynthesis, the main functions of a leaf.

e) Recognize the structure and function of the flower and fruit and the different ways seeds are spread.

f) Understand that the functions of the root, stem, leaf, and fruit are interrelated.

g) Be aware through observation with a microscope that a plant is made up of cells.

What’s my target?

All living things are made up of cells. The cell wall helps the cell to keep its shape. The nucleus controls everything that happens in the cell. The cytoplasm goes around the nucleus. The cytoplasm is like a gel. There are chloroplasts that contain chlorophyll. The chlorophyll is needed to help the plant make its food. You can use a microscope to observe plant cells, such as an onion’s epidermal cell.

Things I need:

Microscope Glass slide Cover slip Iodine Onion

What do I need to do?

1. Remove a single layer from the inner side of the onion and place it on the glass slide.

2. Put a drop of iodine on the onion piece and place a cover slip on top. Make sure all the air bubbles are pushed out.

3. Look through the microscope under 4x, 10x and 40x magnification.

What happened?

Draw a picture of what you saw under the microscope.

What did I learn?

1. What are all living things made up of?

___________________________________________________________

2. What does the cell wall do?

___________________________________________________________

3. What does the nucleus do?

___________________________________________________________

4. Label the cell wall and the nucleus on your picture above.

Nucleus

Cell wall

Chloroplast

1

What’s my target?

The roots of a plant usually grow down into the ground. Root hairs on the root take in both water and minerals (food). The roots also hold the plant firmly in the ground.

There are different types of roots. Plants can have fibrous roots, adventitious roots, aerial roots, prop roots or a tap root.

Things I need:

1 carrot Large beaker Water Food coloring Knife

What do I need to do?

1. Half fill a large beaker with water. Add a few drops of dark food coloring.

2. Cut the end tip off the carrot and place it in the beaker.

3. Put the beaker in the sunshine. After a few days, take the carrot out and cut it in half. Observe what happened.

What happened?

Draw a picture of the carrot’s cross section after you cut it in half.

What did I learn?

1. What happened to the food coloring?

___________________________________________________________

2. What 3 things do roots do?

___________________________________________________________

___________________________________________________________

___________________________________________________________

3. What type of root is a carrot?

___________________________________________________________

Tap root Adventitious roots Prop roots Fibrous roots

2

What’s my target?

The stem is the part of the plant that is above the ground. It supports the plant so that it can grow upwards.

The vascular tissue inside of the stem allows water and minerals to be taken around the plant. Water is taken up through the xylem. The minerals (food) are taken up through the phloem.

Things I need:

Test tube Beaker White flower Colored ink Scissors Bowl

What do I need to do?

1. Add water to the test tube. Put drops of colored ink into the test tube. Put the test tube into a beaker.

2. Put the stem in a bowl of water and cut the bottom of the stem at an angle.

3. Put the stem into the colored ink. Leave it for a few hours and observe what happens.

What happened?

Draw a picture to show what happened to the flower.

What did I learn?

1. What happened to the food coloring?

___________________________________________________________

2. What 3 things do stems do?

___________________________________________________________

___________________________________________________________

___________________________________________________________

3. What goes through the xylem?

___________________________________________________________

Xylem

Phloem

3

What’s my target?

Water needs to travel to all parts of a plant for it to stay healthy. The water moves in the xylem through the stem into the leaves. On the underside of the leaf are very small holes. These are called stomata. Some of the water that travels into the leaves exits through the stomata. This is called transpiration.

Things I need:

2 test tubes 2 large Ziploc bags 2 leaves Vaseline Test tube holder

What do I need to do?

1. Put the first leaf in a test tube filled with water. Cover the leaf with a Ziploc bag.

2. Cover the second leaf with Vaseline. Put it in a test tube filled with water. Cover the leaf with a Ziploc bag.

3. Observe the Ziploc bags throughout the lesson.

What happened?

Draw a picture to show what happened in both the Ziploc bags.

What did I learn?

1. What happened in the Ziploc bag with the leaf that wasn’t covered in Vaseline?

___________________________________________________________

2. What is this process called?

___________________________________________________________

Roots absorb water.

Water goes up the xylem into the leaves.

Some water leaves through the stomata.

4

What’s my target?

Photosynthesis is the process that plants use to make their food. It happens mainly in the leaves of the plants.

The leaves contain a green chemical called chlorophyll that is found in chloroplasts. The chlorophyll absorbs the light energy from the Sun. Energy from the Sun is the first thing needed for a plant to make its food.

Things I need:

2 carrot tops 2 petri dishes Water

What do I need to do?

1. Put one carrot top in a petri dish and place it outside under the sun. Provide it with water on a regular basis.

2. Put the other carrot top in another petri dish and place it in a dark cupboard. Provide it with water on a regular basis.

3. Wait for a week and compare both plants. Observe any differences.

What happened?

Draw a picture to show what happened to the two carrot tops.

What did I learn?

1. What happened to the leaves on the carrot top that was put in the cupboard?

___________________________________________________________

2. Why did this happen?

___________________________________________________________

___________________________________________________________

Chloroplasts can move to maximize the amount of sunlight they absorb. Without sunlight, the leaves can’t make chlorophyll so the leaves won’t stay green.

5

What’s my target?

In the process of photosynthesis, not only does the plant need water and the energy from the sunlight, but it also needs carbon dioxide from the air. The carbon dioxide enters the leaves through the stomata. One of the things the plant makes as the water and carbon dioxide combine is oxygen. The oxygen exits the plant through the stomata on its leaves. Oxygen is the important gas that humans need to survive.

Things I need:

Lettuce Jar Petri dish Water

What do I need to do?

1. Fill a jar with water and put in some lettuce.

What happened?

Draw a picture to show what happened to the lettuce in the water.

What did I learn?

1. What could you see in the water that showed a gas was being made?

___________________________________________________________

2. What gas did the plant make?

___________________________________________________________

3. What is the name of the tiny hole that allows the gas to enter and exit the leaf? ___________________________________________________________

Water

Carbon dioxide Oxygen

2. Fill the jar to the top with water and put a petri dish on top. Turn the jar upside down.

3. Add water to the petri dish and leave it in a bright area. Observe what happens to the lettuce.

6

What’s my target?

The process of photosynthesis can be shown as an equation:

Carbon dioxide + Water + Sunlight (energy) = Oxygen + Food

Oxygen is important for animals, but the most important thing that the plant makes is its food (carbohydrates). Most of the food is used to help the plant grow. Plants don’t need to use all the food it makes straight away, so the extra food is stored as starch.

Things I need:

Hotplate Ethanol 3 beakers Tweezers Paper towels Iodine solution Petri dish Leaf What do I need to do?

1. Use tweezers to put a leaf into boiling water. Let it boil for 2 minutes.

2. Use tweezers to take the leaf out of the boiling water and put it in hot ethanol for 2 minutes.

3. Use tweezers to take the leaf out of the hot ethanol and put it in room-temperature ethanol for 2 minutes.

What happened?

Draw pictures to show what the leaf looked like at each of the steps.

What did I learn?

1. What is the equation for photosynthesis?

___________________________________________________________

2. Why do you think a plant makes starch?

___________________________________________________________

___________________________________________________________

You can show if a plant makes starch by putting iodine on it. If it turns black, it shows that the plant made starch.

4. Use tweezers to take the leaf out and dry it paper towels. Put the leaf into a petri dish that has iodine in it. Observe what happens.

Step 1 Step 4 Step 3 Step 2

7

What’s my target?

Flowers help to make new plants. Some flowers have male parts and others have female parts. Some flowers have both male and female parts. The male parts are called stamens and are made up of the filament and anther. The anthers contain pollen. The female parts are called pistils. At the top of the pistil is the stigma which is sticky and traps the pollen from the male part. The pollen goes down the style to the ovary, which contains eggs. These eggs turn into seeds after the pollen joins with it.

Things I need:

Flower

What do I need to do?

1. Look at a flower and draw the male and female parts. Label them.

What happened? My labeled flower picture.

What did I learn?

1. What is the male part of the flower called?

___________________________________________________________

2. What is the female part of the flower called?

___________________________________________________________

3. In what ways can the pollen from the anther get to the stigma?

___________________________________________________________

___________________________________________________________

4. How are seeds made?

___________________________________________________________

___________________________________________________________

8

What’s my target?

When the seeds are made, they are protected by the part of the plant called a fruit. The fruit develops from a plant’s ovary. Fruits can be described as either succulent or dry. Succulent fruit have thick, juicy layers, like apples and oranges. Dry fruit are dry cases, such as nuts and pods.

Things I need:

Different fruit Knife Colored pencils

What do I need to do?

1. Look at the outer structure of the fruit and draw it.

2. Cut the fruit open and look at the inner structure. Draw the details.

3. Explain the features of the fruit you examined. Include information about the shape, size, color, texture and whether it is a succulent or dry fruit. What happened?

Name of fruit Outer view Inner view Features

What did I learn?

1. Why do plants make fruit?

__________________________________________________________

After the pollen and eggs join, they turn into seeds. The ovary changes into the fruit.

9

What’s my target?

Seeds are carried away from their parent plant so that they don’t have to fight for space, light and water. Different plants have different ways of dispersing their seeds. Some plants rely on animals to eat the fruit and then pass out the seeds in their droppings. Other plants make fruit that can hook onto the fur of animals. Some fruit and seeds float away in rivers and oceans. Other plants create fruit that explode and fling away their seeds. Other plants create fruit and seeds that are light and can be blown away by the wind.

Things I need:

Origami paper

What do I need to do?

1. Use origami instructions to help you make a paper version of the maple seed.

2. Drop it from a high place and observe what happens.

What happened?

Stick your origami maple seed below.

What did I learn?

1. How does a maple seed move away from its parent plant?

___________________________________________________________

2. What methods do other plants use to disperse their seeds?

___________________________________________________________

Maple seeds

A burr that hooks onto animals.

10