1. Monday, October 3, 2011

2. Materials Triple beam balance Light microscope Dissecting microscope
Slides and cover slips
Petri dishes
Pipettes
Paper towels
Scoops
Tape
Sharpies
Tweezers
Soil Samples

3. Agenda Microscope lecture Collect soils data Play with samples
Record observations

4. Soil Samples
Get out your soil samples and get the dry weight of each sample
Record your results: soil dry mass and water mass

5. General Microscope Care
Always carry with 2 hands
Only use lens paper for cleaning
Do not force knobs
Keep objects clear of desk and cords
Teacher demonstrates how to hold the microscope, where the lens paper is located and how to use it. Students will be invited to turn the knobs and observe the stage as it moves up and down. Teacher will demonstrate how to store the microscope.

6. Light Microscope Parts
Eyepiece
Body Tube
Revolving Nosepiece
Arm
Objective Lens
Stage
Stage Clips
Coarse Focus
This is the exact version of the microscope used in class. Students will be identifying the parts on the microscopes at their desks as we go along and what their functions are.
Diaphragm
Fine Focus
Light
Base

7. Using the Light Microscope
Always observe using the LOWEST POWER objective first.
Focus using the COARSE ADJUSTMENT KNOB to bring the object into focus. Bring the object into sharp focus by using the fine adjustment knob.
Focus, and then move to a higher power objective, if needed.
Use only the FINE ADJUSTMENT KNOB when using the HIGHEST (longest) POWER OBJECTIVE.
Keep both eyes open to reduce eyestrain.
Determine total magnification of the object by multiplying the power of the ocular (10x) the power by the power of the objective.

8. Preparing a Slide
Using a pipette or dropper, add a drop of water or another solvent to a clean microscope slide. Then, place the specimen in the water.
Place the edge of a coverslip on the slide so that it touches the edge of the water.
Slowly lower the coverslip to prevent the formation of air bubbles.

9. Dissecting Microscope Parts

10. Activity
Make a slide for each of your water samples (take sample from the bottom).
Observe under low power and high power
Record observations
Add a scoop of each soil sample to a labeled petri dish

11. Field Notebook Observations
For each drawing include the following information:
Date
Sample Site Name and Number
Magnification
Drawing
General observations