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Backyard Explorer 3 to 5 / Week 05 / Wednesday
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Week 05 · Plants: Built From Air and Water

Wednesday

Water on the move
// Where the stuff of a plant really comes from
⏱ about 15 min

Wednesday: Water on the Move

Raven sets a glass of blue water on the workshop bench. A pale celery stalk stands in it.

"Nothing is happening," says Rocket after one minute.

Nova glows softly. "Roots and stems work slowly," she says. "Scientists wait."

Hours later Rocket races back. The leaves at the top have blue lines in them.

"The water climbed!" he shouts. Raven snaps the stalk and shows him tiny blue dots inside.

Tubes inside the stem

Water enters a plant at the roots. But the leaves need it most.

How does water get from the bottom to the top?

The stem is full of thin tubes. They run from the roots all the way to the leaves.

Water travels up those tubes. It even climbs to the top of a tall tree.

Water leaves through the tiny holes in the leaves. Then more is pulled up from below.

You can see the tubes in a celery stalk. They are the strings you notice when you bite it.

Make water climb

You will watch colored water travel up a stem.

  • A stalk of celery with leaves, or a white flower on its stem
  • A clear glass or jar
  • Water and a few drops of food coloring
  • Your notebook and a pencil
Safety first
A grown-up cuts the bottom of the stalk with a knife.
Food coloring stains. Keep it away from clothes and off your hands.
Do not eat the celery after the experiment. It has coloring in it.
  1. Fill the glass halfway with water. Add food coloring until it is dark.
  2. Ask your grown-up to cut a fresh slice off the bottom of the stalk.
  3. Stand the stalk in the colored water. Write the time in your notebook.
  4. Check it after one hour, after three hours and the next morning.
  5. Each time, look at the leaves. Draw what you see.
  6. At the end, ask your grown-up to cut the stalk in half. Look for colored dots.
CheckTimeWhat the leaves look likeHow far did the color climb?
1
2
3
WHAT WILL HAPPEN?
  • Read the question.
  • Tap your answer.
Where will the colored water travel?
What are the colored dots inside the cut stalk?
Why does the experiment take hours?
StatementTrue or false?
Water enters most plants through the leaves.?
Thin tubes in the stem carry water up.?
Water can climb to the top of a tall tree.?
The strings in celery are the water tubes.?
WHY THIS EXERCISERoots take in water. Tubes in the stem carry it up, even in tall trees.
Water enters a plant through its ____.
Water travels up the stem through thin ____.
In which plant part does water leave through tiny holes?
WHY THIS EXERCISEWater leaves through the tiny holes in the leaves, pulling more water up from below.
Draw what you predict the celery will look like tomorrow morning. Color where the water will be.

Patient science! Tomorrow we look closely at the leaf, the food factory of the plant.

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