LESSON 2
THE WOWBUG: GETTING
A
CLOSER LOOK
Name:
Class:
Date:
Inquiry Master 2.1
The Compound Microscope
Eyepiece—Usually contains a 10× lens
Nosepiece—Holds the objective
lenses; rotates to enable
changing magnification
Arm—Supports the upper
part of the microscope;
serves as a handle
Objective Lenses—Used in
combination with the eyepiece
to provide a range of magnifications, usually from 40× to
400×
Stage Clip—Usually one on
each side of hole in stage;
helps to hold slides in place
Stage—Supports the slides
Coarse Adjustment Knob—
Raises and lowers the stage
or objective lenses
Diaphragm—Wheel or lever
that adjusts amount of light
that passes through hole in
stage; provides proper contrast
Light—Sends light through the
hole in the stage to illuminate
specimen on slide
© 2003 National Academy of Sciences
Base—Supports the
microscope; serves
as a handle
Fine Adjustment Knob—
Raises and lowers the stage
or objective lenses a tiny distance for exact focusing
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LESSON 2
THE WOWBUG: GETTING
A
CLOSER LOOK
Name:
Class:
Date:
Student Sheet 2.3A
Guidelines for Scientific Drawings
An acceptable scientific drawing includes the following 10 elements:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
The drawing is made with a sharp, No. 2 pencil.
The size of the drawing is proportional to the way it appears in the field of view.
The magnification and/or the diameter of the field of view is printed just below the circle.
The title appears in upper-case letters just below the magnification.
The lines used for labeling end at, or just inside of, the feature being identified.
A ruler is used to draw the lines for labels.
Labels are printed neatly outside the field of view and parallel to the bottom of the page.
The magnification, title, and labels are printed, not written in cursive.
There are no noticeable erasure marks.
Measurements are printed within parentheses to the right of the title.
This drawing of cells from the bulb (leaf) of the onion is considered acceptable because it follows
each of the 10 guidelines.
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LESSON 2
THE WOWBUG: GETTING
A
CLOSER LOOK
Name:
Class:
Date:
Student Sheet 2.3B
Drawing Your WOWBug
Directions In the circles below, draw the images requested in Inquiry 2.3. The circles represent the
field of view as seen through a compound microscope.
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
© 2003 National Academy of Sciences
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LESSON 2
THE WOWBUG™: GETTING
A
CLOSER LOOK
Student Sheet 2.3B (continued)
From Procedure Step 7
________: Diameter of field of view (mm) at low magnification
________: Diameter of the field of view (mm) at medium magnification
________: Diameter of the field of view (mm) at high magnification
________: Estimated WOWBug body length (mm) at low magnification
________: Actual WOWBug body length (mm) at low magnification
Reflecting on What You’ve Done
A. Explain two ways in which the compound light microscope is an improvement over the microscope developed by Antony van Leeuwenhoek.
B. List three ways in which lenses are used as tools of science, in addition to their use in the compound microscope.
C. How did the diameter of the field of view change when you changed the compound microscope’s
objective lenses?
D. What characteristics of the WOWBug did you observe that suggest it is an insect?
(continued)
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LESSON 2
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A
CLOSER LOOK
Student Sheet 2.3B (continued)
E. In what ways did your WOWBug remove the flour dust from its body? List two reasons why you
think grooming would be important to a WOWBug. (Hint: Why is grooming important for you?)
F. According to the reading selection “Intriguing Insects,” how are parasitic wasps, such as
WOWBugs, important to humans?
© 2003 National Academy of Sciences
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