Amoeba This!!!! Amoeba That!!!!

 

Summer Research Program for Science Teachers

 

Staceyann Hood

Pathways College Preparatory

August 2008

 

 

 

Course: Living Environment or Science Inquiry

Grade: 8th & 9th Grade

Unit of Study: Ecology

 

Objectives:

Introduction- Students will produce a sample of pond water or soil from their neighborhood.  They will then discuss the importance of Protozoa to the environment and what effects they would have on the environment if they were non-existent.  Students would have to complete pre-reading and research prior to class) 

 

Agenda:

  1. Students will watch a video from Google Video (http://video.google.com/videoplay?docid=7593803924505341772&q=Amoebae&hl=en), (http://video.google.com/videoplay?docid=7606425584462985016&q=Amoebae&ei=i8R0SMyCOIaW-QGP7vScCw&hl=en) are both good starter videos for students to watch what an amoebae looks like and how to observe it on a microscope. These videos give information about how to observe an amoeba under a microscope.
  2. Students will analyze their water or soil samples using a compound microscope and record their findings on the Protozoa worksheet.
  3. Students will use their resource keys to identify what organism where found in their sample.
  4. Students will create a description chart describing the area where they collected their sample, date, time, and location of their sample. In addition students will also compare, shape, locomotion, cyst formation, and feeding traits. This information will be shared and compared with other source samples.
  5. Discussion- why were certain organism found in a particular sample? What are some of the factors that contribute to these types of organism growing in this area? What is the relationship to your organism and the ecosystem it lives in?
  6. Students will then design an experiment using altered variables to see the effects on Amoebae.

 

Methods & Materials

  1. Students will be in groups of four. Each student will prepare a wet mount of soil or pond sample, using a compound microscope they will observe sample for organisms.
  2. Each student will record their findings using the worksheet provided to depict what is seen on low, medium and high magnification.
  3. Once students have observed their findings each group will create a chart using large chart paper. The chart will include the location where the sample was found, the date, whether it was a soil or pond, and what types of organism were found.
  4. Each group will share out their findings.
  5. The entire class will then discuss why different organism was found in different locations and what are some possible explanations for this data finding.
  6. Students will reflect as a group by choosing one organism in their samples and its importance to the ecosystem. ( DVD “The Branches of the Tree of Life”, and internet access will be available)
  7. Extension- each group will then design an experiment using the Amoeba kit from Carolina to determine ecological characteristics. For example, how do different species share or compete for resources to permit survival? How does social amoebae partition their niches? Do different species have different food preferences? Do different mating strains influence each other's feeding?
  8. Each group will be given a water sample that contains different species of Protozoa. Students will then prepare a wet mount on a microscope slide to prepare for observation.

 

Suggested Discussion Points – Students can discuss how energy is transferred in ecosystems and the importance of Amoebae. Students can also study the Hardy Weinberg Population of one species and the survival strategies Amoebae’s use to sustain life.

 

Guided Questions:

1) Why are some kinds of protozoa found in certain samples and not others?

2)  What might happen to the pond if a quantity of antibiotics were accidentally dumped into the pond killing all the existing protests?

3) One summer is very dry and hot, a certain pond dries almost completely.  The city Park’s Department, in an effort to save the pond refills the pond with water from the city’s drinking supply.  What predictions would you make about the protozoa population of the pond before and after the refill with drinking water?

4) What roles do you think Protozoa play in an aquatic ecosystem?

Teacher Resources:

 

http://www.biology-resources.com/amoeba.html (This is a website that allows you print worksheets about Protozoa. You can use this as a reference key for students)

 

 

http://www.carolina.com/product/food+preferences%2C+competition%2C+and+cooperation+in+social+amoebae+kit.do?keyword=amoeba&sortby=bestMatches

Amoeba kits assist in designing the experiments.

 

NYS Science Standards

 

Key Idea 1

Beyond the use of reasoning and consensus, scientific inquiry involves the testing of proposed explanations involving the use of conventional techniques and procedures and usually requiring considerable ingenuity.

 

1.1c in all environments, organisms compete for vital resources. The linked and changing interactions of populations and the environment compose the total ecosystem.

 

1.1d The interdependence of organisms in an established ecosystem often results in

Approximate stability over hundreds and thousands of years. For example, as one popu-

lation increases; it is held in check by one or more environmental factors or another

species.

 

1.1f Every population is linked, directly or indirectly, with many others in an ecosys-

tem. Disruptions in the numbers and types of species and environmental changes can

Upset ecosystem stability.

 

Key Idea 6

Plants and animals depend on each other and their physical environment.

 

6.1f Living organism has the capacity to produce populations of unlimited size, but environments and resources are fine. This has a profound effect on the interactions among organisms.