1. Bellwork Why do scientists use Microscopes?

2. Microscopes

3. Target #9- I can describe the compound light microscope
Microscopes are tools that extend our vision by making objects like cells, and atoms visible
Compound Light Microscope
Shines light through a specimen and has two lenses to magnify an image
Specimens must be mounted on a slide
Specimen must be thin enough for light to pass through

4. Target #10- I can describe the 4 basic parts of a light microscope
There are 4 major parts of a compound light microscope
Eyepiece
Also known as the ocular lens
Magnifies the image 10 times (10x)
Objective Lens
Light passes through the specimen and then through the objective lens
Located directly above the specimen
Enlarges the image of the specimen
Stage
A platform that supports a slide holding the specimen
Light source
Either a light bulb or light reflected

5. Target #11- I can label all the parts of a light microscope
Ocular lens (Eyepiece)
Body Tube
ARM
Nosepiece
OBJECTIVE LENSES
STAGE
STAGE CLIPS
COARSE ADJUSTMENT KNOB
DIAPHRAGM
FINE ADJUSTMENT KNOB
LIGHT SOURCE
BASE

6. Target #12- I can explain how to calculate the power of magnification
Microscopes vary in magnification abilities
Magnification: the apparent increase of an objects size
The degree that an object is magnified in a microscope is called the power of magnification
To compute the power of magnification of a microscope, multiply the magnification of the strongest objective lens by the power of the ocular lens
Ex: if the strongest objective lens is 100x magnification, multiply by the objective lens which is usually 10x, then the total magnification is 1,000x

7. Checking for Understanding
On a light microscope an objective lens magnifies the view of some pond water 25 times, and the ocular lens magnifies it 10 time further. What is the final magnification of the image?

8. Target #13- I can describe electron microscopes
To examine specimens in more detail, scientists commonly use an electron microscope
Electron microscopes use a beam of electrons to produce an enhanced image of the specimen
More powerful in magnification and resolution than light microscopes
Images are produced in black and white, but are usually colorized to show detail via computer
Specimens are not living ones
Two types
Scanning electron microscope
Transmission electron microscope