1. Microscope
Magnification

2. Image orientation

3. Depth of focus

4. Ocular lens (eyepiece) is 10X
4x objective lens
10x objective lens
40x objective lens
100x objective lens
To get total magnification you multiply the two together:
(10X) (4X) = 40X magnification
(10x) (10X) = 100X magnification
(10X) (40X) = 400X magnification
(10X) (100X) = 1000X magnification

5. Elodea Plant
Leaf on slide
40X
100X
400X

6. Cheek Cell
40X
100X
400X

7. How much bigger are the items viewed under a microscope?
An average plant cell is 30 micrometers wide.
How big is that under:
4X objective?
10X objective?
40X objective?
100X objective?

8. Metric Conversions

9. Metric conversions
Because items are magnified so greatly under a microscope, it may not be appropriate to use the same units to discuss the size of something viewed with the naked eye versus the size it appears under a microscope.
Using the example from the previous slide, an average plant cell is 30 micrometers in diameter. What does the diameter appear to be under a microscope using the 10X objective? State your answer in centimeters.

10. Practice Question
The lenses shown in the photo are known as what?  A.  projection lenses
B. eyepiece lenses
C. objective lenses
D. power lenses

11. Practice Question
All the lenses shown in the photo are part of a structure of the microscope known as the what?
A. rotating lenspiece
B. stage
C. revolving nosepiece
D. arm

12. Practice Question
How is the total magnification of the microscope is obtained?
A. multiplying the power of the objective lenses together.
B. multiplying the power of the objective lens by the power of the eyepiece lens.
C. dividing the power of the objective lens by the power of the eyepiece lens.
D. dividing the power high power objective lens by the power of the low power objective lens.

13. Practice Question
What is best used as an adjustment on a microscope to bring a specimen into focus at high power?
A. Fine focus knob
B. Objective lens
C. Coarse focus knob
D. Eyepiece