The Effect Of The Fertilizer On Algaes

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Guided Inquiry • Real-World Lab

Chapter 3 Lab The Effect of Fertilizer on Algae

Problem
How do excess nutrients affect the growth of algae?

Introduction
Asprimary producers, algae form the base of the food web in the upper layers of the ocean and in freshwater lakes and ponds. The term algae is used to describe a range of organisms from the large brown kelpfound attached to rocks at the seashore to the tiny green algae found in fish tanks. Like other plants, green algae need nitrogen, phosphorus, and potassium in order to grow. All three nutrients mustbe available for the algae to grow and reproduce.
Have you ever seen a pond with a thick, green layer of algae on its surface? This layer is a sign that the pond ecosystem has been disturbed bythe presence of too much nitrogen or phosphorus in the water. Fertilizers contain these nutrients, which can end up in bodies of water when rainfall flows downhill from farms.
In this lab, you willwork with Chlorella, a type of algae that is commonly found in ponds and aquariums. You will compare the growth of Chlorella when nutrients are limited and when nutrients are plentiful.

Skills FocusPredict, Compare and Contrast, Infer

Build Vocabulary
|Term |Definition |
|nutrient |Achemical substance that an organism needs in order to stay alive |
|excess |An amount of something, such as a nutrient, that goes beyond, or exceeds, the |
||amount that is needed |
|control |The setup used to test the results of a managed, or controlled, experiment. ||summarize |To state briefly or sum up; to prepare a brief statement or summary |

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Materials
• 2 test tubes •...