Algae--Where does it Live?

Mary Ellen Dote St. Cletus School
700 W. 55th Street
La Grange, IL 60525
(708) 352-4820

Objectives:

1. To understand what green algae is and where it grows.
2. To test the growth of algae in four different types of water - lake water,
well water, distilled water and tap water.
3. To watch and record the growth of algae.

Materials needed:

Types of water: microscopes
Tap slides (concave)
Well cover slips
Distilled medicine droppers
Lake Michigan pipette
pencils
Four (4) quart jars plastic or glass covers

Strategy:

Display a gallon of lake or pond water to the class. Have students observe the
water and describe what they see, especially the "green growth". Discuss what
they think this growth is, such as, plant life. Name the plant -- ALGAE.

The teacher will then distribute a worksheet and have the students list the
characteristics or traits of the algae plant. They will also hypothesize about
which type of water algae can grow in best (distilled, lake, well or tap) and
why.

Set up two microscopes with a sample of chlorella--a type of green algae. The
class will then be able to identify algae in their projects.

Divide the class in groups. Each group will have a sample of well, tap,
distilled and lake water. They will also have a sample of chlorella. They
will place a drop of chlorella and a drop of one type of water on the microscope
slide. Students should observe and draw a picture of what they see. They will
observe four types of water.

The teacher will distribute four quart jars labelled WELL, TAP, DISTILLED and
LAKE water. Each jar will be filled approximately 3/4 full of the above types
of water. Using a pipette, 10 cc of lake water containing algae will be added
to each type of water. A pencil will be placed over the jar and covered with
a plastic or glass lid to allow air to enter.

Observe the algae growth in each jar for 2 to 3 weeks. Record results twice a
week on a chart by taking a sample of the water and placing it under the
microscope. They may also observe the growth (or lack of growth) without a
microscope but this may be more difficult to record results.

Extensions:

You may want to check the pH level of the water for different results.
You may want to add fish (same kind) to each container of water to see if this
affects the growth of algae.
You may also duplicate a culture of algae in lake water, prepared as described
above. Shield algae from sunlight with transparent colored paper to determine
which color of light is necessary for algae growth.

Evaluation:

Did the class understand the scientific method used in this experiment? (same
jars, same amount of water, same amount of algae in each type of water.)
Were the students able to observe and record results?
Did they questions results?




LAB SHEET

GREEN ALGAE--WHERE IS IT FOUND



1. List 2 or 3 characteristics or traits of green algae.




2. HYPOTHESIS (OR SCIENTIFIC GUESS). In which type of water will green algae
grow the most? Will it be well water, distilled, tap or lake water. Why?



3. Using a microscope, draw the algae you see in a drop of each type of
water. Do this twice a week for at least two weeks.
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