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Complexity level:
2
Project cost ($):
Time required:
Once preparations are finished, the flowers will sit for at least 24 hours, then conclusions will be made after.
Material availability:
Safety concerns:
Safety guidelines for cutting flower stems should be followed.

Abstract

Have you ever wondered how flowers in a vase can survive without their roots? The water in soil travels up the roots of flowers to their leaves. Even without roots the stems of flowers can carry water to their leaves. In this science project you will actually see how flowers work.

Objective

In this science project you will change the color of a flower's petals with the water you place them in, watching how flowers get their nutrients.

Background

Flowers get their nutrients by a process called Photosynthesis. They take in carbon dioxide (what we breathe out), sunlight, and water from the soil and turn it into oxygen and energy. The water is absorbed into the roots and travels through the vascular system in the stem to the leaves as seen in Figure 1.

Flowering plant anatomy

Figure 1: The cross section of a flower shows where water is transferred from the root hairs, to the lateral root, to the primary root, into the vascular system and to the leaves and pedals.

By looking at Figure 1 it is evident that the vascular system is the most important component for the flower's intake of water. When flowers are bought at the store they have no roots, yet they survive without them because the vascular system is located in the entire stem.

When flowers are put into a vase full of water, after time the water level goes down. This is because the flower is "drinking" through a process called transpiration. Transpiration occurs when the water on leaves and pedals evaporates, cohesion pulls the water from the vase, up the stem, and back into the leaves and flowers. Cohesion is known as the attractive force between water molecules.

Scientific Terms

Flower , Leaf Blade, Vascular System, Primary Root, Lateral Root, Root Hairs, Root Cap, Photosynthesis, Transpiration, Evaporation, Cohesion

Materials

* Three white daisies

* Three clear glasses to use as vases

* Two different colors of food coloring, blue and red preferred

* One cutting board

* One knife to cut the stems

* Water

* Measuring cup for the water

* Ruler

* Pencil and paper

Procedure

1. Copy and use the chart below for data collection.

BLUE

RED

CLEAR

Length of stem

8 in

8in

Amount of water to begin

2 cups

Drops of color

25

25

0

Time and date flowers go in water

Description of flower color

Time and date flowers go out of water

Amount of water left

Amount of water used by the flowers

2. Lay one white daisy horizontal on the cutting board with the flower side on the left. With a ruler measure 8 inches of the stem from the flower. Cut the stem at the 8 inches mark at an angle Not a flat cut, this will increase the amount of water the flower can take in. Record the length of stem in the chart.

preparing the flowers for our science project

3. Repeat step 1 with the remaining two white daisies.

4. Take one clear glass. Fill the measuring cup with 2 cups of water. Empty the measuring cup into the glass. Record the amount of water measured in the chart.

5. Take the blue food coloring and add 25 drops into the water. Pick the glass up and swirl softly to allow the color to fully mix with the water.

6. Repeat step 4 with a new clear glass. Take the red food coloring and add 25 drops into the water. Pick the glass up and swirl softly to allow the color to fully mix with the water.

7. Repeat step 4 with the remaining clear glass. Add no coloring.

8. Now set the three different colored glasses on the table in front of you. Place one white daisy in each glass.

fun with flowers science experiment - observing color change

9. Record the exact time and date the flowers are placed in the glasses in the chart.

10. Wait exactly 24 hours.

11. Record the time and date when you view the flowers in the chart.

12. Describe how the three daisies look in the chart.

13. Take one flower out and fill the used water into the measuring cup. Record the amount of water left over. Then subtract and record the amount of water used in 24 hours in the chart.

14. Repeat step 13 with the remaining two glasses.

Discussion

Reviewing your completed chart and the flowers, what can you conclude? As you can see the two flowers placed in the dyed water have completely changed color. Also you can observe that all three glasses have much less water in them compared to yesterday. How does the dye in the water transfer to the color of the flower pedals? With the stem being cut at an angle instead of straight it allows more water to be pulled up the stem. If cut straight it could sit flat on the bottom of the glass which would greatly reduce the amount of water being pulled up the stem.

As the 24 hours pass the water molecules on the surface of the leaves and flower pedals evaporate. Cohesion between the molecules causes water in the glass to be pulled up the stem to replace the evaporated water on the leaves and flower pedals. This transpiration is what allows us to change the color of the flower pedals. Without transpiration flowers would be deprived of the nutrients found in soil that are vital to their survival and the process of photosynthesis.

Questions & Answers

How does placing a white flower in colored water change the color of the flower?

Through the process of transpiration the dyed water travels through the stem and onto the flower pedals.

What makes the flower keep on ""drinking""

Cohesion when the water on the surface of the leaves and flower pedals evaporates.

How can the angle of the cut stem affect its ability to intake water?

If the stem is cut straight it might lay flat at the bottom of the glass and pull up less water, with a cut angle, the stem will receive constant water.

Make it Your Own

Does having dye in the water effect the amount of water consumed by the flower in a 24 hour period? Compare the water levels of the two different colors used in 24 hours to the clear water levels. Is there a difference?

Want to get creative? Want to dye a flower two different colors at the same time? Evenly cut the stem of the flower in the middle all the way up to the flower, stop cutting about half an inch below the flower. Then place each piece of stem into two different colored glasses. Wait 24 hours and see how two different colors dye the pedals. Record the patterns the different colors make.

In this project you successfully dyed a white daisy. Is it possible to turn it back to white? After the dying process is over place your dyed daisy into 2 cups of fresh clear water, just like in the original project. Wait 24 hours. Has the daisy's color changed? Is it faded? If it still has some color in it then wait another 24 hours. Record all of your observations.

References

A great place to start researching terms important for this project is the encyclopedia.

1998. "Botany: Plants Parts and Functions" The University of Arizona, College of Agriculture. 12/06/13 http://ag.arizona.edu/pubs/garden/mg/botany/plantparts.html

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