Tom Robinson - The Everything Kids Science Experiments Book: Boil Ice, Float Water, Measure Gravity-Challenge the World Around You!

Life. We all have it. The world around us is full of it, from the birds in the air to the fish in the sea and all the land animals in between. But how does life really work? If you can answer that question, you will gain insight into one of the most widely studied topics in the natural world.

Humans and other animals are very complex creatures. So lets first consider plants. Plants seem to be simple examples of the way life works. You plant them in the ground, water them, and let the sun shine on them. Pretty soon, they grow, they bloom, and then they die. But inside a plant, there are processes happening that we dont see processes unlike anything else we encounter. Lets begin to understand these processes with what everyone knows is the most important resource a plant can get: water.

How does water get from the ground to the leaves of a plant?

4 full glasses of water at room temperature Red, blue, green, and yellow food coloring 3 white carnations from a florist Sharp knife

1. Mix one color into each of your four glasses. The stronger the color of the water, the more effective the experiment will be.
2. Place your first carnation into the glass of your choice. You may need to trim the stem if its too long.
3. Place your second carnation into another glass.
4. Take your final carnation and, with an adults help, slice the stem lengthwise so that it looks like two smaller stems, both of which remain attached to the flower.
5. Place one half of the stem into your third glass of colored water and the other half into the fourth and final glass.
6. Place the flowers out of the sunlight and wait a day or so. Then look at each of the flowers.

Through a process called capillary action, water travels up through the stems of plants until it reaches the outermost parts of the flowers. You saw this when the flower of each carnation turned the color of the water it was sitting in. Even more interesting is that the split stem produced a flower with both colors in it. You could easily repeat this experiment with other flowers and other colors to see if they behave in the same way. Celery stalks with the leaves on also work well in this experiment.

capillary action: the process that allows water and other nutrients to move up from the ground to all parts of a plant.

FOLLOW-UP

When you water the plants in your yard, should you water the leaves or the ground around the bottom of the plant?

(The answers to all Follow-Up Questions are at the end of the book. The number of the superscript marks the answer in the back.)

Why did the silly scientist keep his shirt on when he took a bath? Because the label said Wash and Wear.

Science Online

ZooNet is a good starting point for information about animals, zoos, and more. Visit www.zoonet.org .

TRY THIS FALLING LEAVES

Some trees stay green the whole year round while others lose their leaves in the fall and winter and grow new leaves in the spring. If youve ever seen trees lose their leaves in the fall, you may have noticed that the leaves turn from green to yellow, red, or orange before eventually falling to the ground.

QUESTION

Where do the leaves get their colors?

MATERIALS

45 spinach leaves

1 drinking glass

Spoon

Nail polish remover ask a parent for help in getting this

Coffee filter

Scissors

Tape

Pencil

PROCEDURE

1. Tear the leaves into small pieces.
2. Place the pieces into the bottom of the glass and mash them together with a spoon.
3. Add several teaspoons of nail polish remover to the leaf mush. Wait until the leaves settle at the bottom of the nail polish remover. If the remover does not cover all the leaves, add enough so that they are totally covered.
4. Cut a rectangle from the coffee filter. It should be slightly narrower than the glass.
5. Tape the rectangle to the pencil and, when the leaves are settled, place the pencil across the top of the glass so that the coffee filter rests in the nail polish remover without touching the leaves.
6. Let the glass sit for several hours.

Cool Quotes

Autumn is a second spring when every leaf is a flower.

Albert Camus, French novelist

WHATS HAPPENING

You should see many colors work their way up the coffee filter. The green you see comes from the chemical that makes leaves green chlorophyll. But you should also see other colors, like red, yellow, and orange. These come from different chemicals that are also found in green leaves.

During the spring and summer, photosynthesis produces so much chlorophyll you can see only the green color in the leaves. But as the days get shorter, less chlorophyll is produced and the green fades away so that you can finally see the other colors. When the green is gone, the leaf is not far from falling to the ground.

FOLLOW-UP

When fall comes, watch the leaves change color. Can you tell what causes this to occur?

chlorophyll: the chemical in plants that makes their leaves green.

photosynthesis: the process by which plants turn sunlight and water into chlorophyll.

Fun Facts

Chlorophyll absorbs red and blue light and reflects green light back to your eyes.

What do you call a scientist who carries a dictionary in her jeans pocket?

A smarty pants!

KIDS LAB LESSONS