I. Principles of Light Microscopy
1. Why do we need microscopes?
-size
2. Who invented the light microscope?
3. What is a compound microscope?
ocular
condenser
total magnification
4. What is more important in microscopy: magnification
or resolution?
5. What is resolution?
LR = limit of resolution
6. What other problems are associated with viewing
biological specimens with a light microscope?
7. How can the contrast of living material be
improved?
II. Tour of the
Freshwater Pond
A. What is a freshwater biome?
B. What are the zones of a pond?
C. Freshwater ponds contain both living and non-living
components
‘Pond Life
Identification Kit’ –from Microscopy UK
1. Abiotic
2. Producer organisms
Look for green!
Rooted
or large
floating plants
Minute floaters
-Flagellated forms:
Euglena
Dinoflagellates
Green
algae: Volvox (colonial)
-Non-flagellated
forms
blue-green
algae
diatoms
desmids
green
algae: Hydrodictyon (colonial); Spirogyra (filamentous)
3. Macroconsumer
organisms
4. Secondary consumers
-ciliates: Paramecium
-amoeba
Invertebrate animals:
D. Pollution (eutrophication)
causes oxygen depletion of freshwater ponds
How
would pollution change the community structure of the pond?
