Exercise 1 – A Bean Water Micro-community & Exercise 2 – A Pond or Stream Water Micro-community

Use Data Table 1 to record your observations and organisms found in the bean water and pond water for Exercise 1 and Exercise 2.

Data Table 1 – Organisms in Micro-communities
Describe
Organisms Bean water Pond water Motile or sessile (reason) Heterotrophic or Autotrophic (reason)

Exercise 1 – A Bean Water Micro-community
Make sketches of the microorganisms found in the water that had beans soaking in it for both the live specimens and heat-fixed microorganisms. Identify cells as prokaryotic or eukaryotic cells. Make your drawing using the highest magnification.

Live Microorganisms
Magnification = _______________ Heat-fixed Microorganisms
Magnification = _______________

Exercise 2 – A Pond or Stream Water Micro-community
Make a sketch of the microorganisms found in the pond water. Identify cells as prokaryotic or eukaryotic cells. Make your drawing using the highest magnification.

Live Microorganisms
Magnification = _______________

Questions:

1. Explain the color differences between the autotrophic and the heterotrophic organisms.

2. Are bacteria large or small organisms compared to eukaryotic cells? Explain your answer.
3. Can you observe any details within the cytoplasm of any of the microorganisms you viewed under the microscope? Elaborate.
4. Which of the following structures would you expect to find in bacteria cells – nucleus, cytoplasm, cell membrane, and/or cell wall?

5. Which of the following structure would you expect to find in eukaryotic cells – nucleus, cytoplasm, cell membrane, and/or cell wall?

6. Are most organisms in the bean water autotrophs or heterotrophs?

7. Are most organisms in the pond water autotrophs or heterotrophs?

8. Are most autotrophs motile or sessile?

9. Are most heterotrophs motile or sessile?

10. Explain the overall differences between the two micro-community environments