1.05 Microscopy LAB
Name:
** When opening your LAB LINKS, it is always best to use Firefox or Internet Explorer. Using a Microscope Pre-lab Instructions/Questions
Below in numerical order are the instructions to follow in order to complete the
prelab for this assignment. Please be sure to read all instructions.
1. Watch Joelle in the video to learn how scientists focus a microscope.
http://www.udel.edu/Biology/ketcham/microscope/testFLV8.html
You may use the microscope provided to you from k12, if you would like
to follow along with her. (Note: your microscope is different than the one in the video,
so it will not have all the parts Joelle discusses.) 2. 3. Open this link: http://www1.udel.edu/biology/ketcham/microscope/scope.html .
This is the link for the Virtual Microscope you will be using to
complete this LAB assignment.
Once the Virtual Microscope page is opened, click on the “Getting
Started, Start Tour” button to review the functions of the
microscope. FOLLOW ALL DIRECTIONS IN THE TOUR! (Note: Make sure
the volume of your computer is turned up.) 4. ANSWER THERE QUESTIONS AS YOU FOLLOW THE TOUR!
a. What objective lens power should you always start with? Highlight the correct
answer.
4x (scanning lens) 10x (low power) b. Which focus knob moves the stage quickly? 40x (high power) 1.05 Microscopy LAB c. Which focus knob moves the stage slowly? d. Which button do you press to look through the virtual microscope? e. Were you able to adjust the ocular lenses so you merged the two circles? f. Where should the center of the specimen be? g. Write a hypothesis about the focus of the specimen and changing between the
powers of the lenses. (Remember: if/then statements!!) Lab Instructions THIS IS A CHECKLIST OF TASKS! As you examine each
of the 4 virtual microscope slides, use the chart below to
help you go through the steps. ** This table is used as a way to check off each
task as you look through the microscope slides**
“e” Onion
Root Tip Bacterial
Capsule Cheek Smear Task 1.
2.
3.
4. Turn on microscope light
Move the rheostat to 10 (light brightness).
Choose the slide in upper right hand corner. 5. Center the specimen on the stage using the knobs
on the right hand side (top) of the microscope. 6. Move stage to top position using the knobs on right
hand side (bottom). Make sure scanning lens is in place (4x) 1.05 Microscopy LAB
7. Click on “switch views” at top of checklist. 8. Adjust the ocular lenses using the eyepieces at
top by dragging until circles overlap. 9.
10.
11. Using the coarse adjustment, focus the specimen
Then use the fine adjustment to focus more
precisely. (The RED circle should be focused)
Adjust lighting using iris diaphragm, if needed. (so
check appears) 12. Change between the four objective lenses using
the rotating nosepiece in bottom lef corner. 13. Once finished with this slide, move on to next
slide by switching views. Lab Questions: (The pictures below are examples of how your slides should look when you
have correctly focused your microscope) 1. How does the letter ‘e’ appear under the microscope? 2. Describe what the onion root tip looks like under the 40x lens. 3. Describe what the bacterial capsule looks like under the 10x lens. 4. Describe what the cheek smear looks like under the 40x lens. 1.05 Microscopy LAB 5. Determining Total Magnification: The eye piece (ocular lens) you “looked”
through on the virtual microscope had a power of 10x. If you were using
the 4x objective lens, what would the total magnification before the
specimen you are viewing? Show your work!! 6. In part ‘g’ of the prelab, you stated a hypothesis. Was your hypothesis
correct? Explain.