Transcript microscopes-4 - Harrison High School

Journal 1
• On a clean sheet of paper, write down
three things you already know about
microscopes, making slides, the cell parts,
and photosynthesis/respiration.
• Also write down at least two things you
would like to know about these topics.
Describe the properties of
microscopes.
• Microscope: a device
used to produce
magnified images of
objects too small to see
with naked eye
• Magnification: increase in
size
Describe the properties of
microscopes.
• Resolution:
increase in detail
• Two types:
• Light microscopes
• Electron
microscopes
Light Microscopes
• Magnifies objects using
light
•Simple microscopes: have
only one lens (magnifying
glass)
• Compound light
microscope: has two
lenses
• Diagram in your book
appendix D pages
1064 & 1065
Parts of a microscope
• Ocular lens: lens near eye
•Eyepiece: holds ocular lens
•Objective lens: lens near specimen
a. high power lens: longer, usually 40 X
b. low power lens: shorter, usually 10 X
Parts of a microscope
•
Nosepiece: holds objective lenses
• Stage: platform supporting specimen
• Diaphragm: regulates amount of light
• Fine adjustment/coarse adjustment: used
to focus on object
• Arm: supports microscope
• Illuminator: light source
Using the microscope:
• Find total magnification: multiply the power of eyepiece
(usually 10X) and the power of objective lens
•When focusing: always start with LOW POWER objective
•Move nosepiece all the way down and focus slowly
UPWARD using the coarse adjustment
Microscope development:
• Hans and Zacharis Janssen:
1590 mounted two lenses in a
tube
• Anton van Leeuwenhoek: early
1660’s used simple microscope
to view blood, rainwater, etc. He
was the first to study nature with
microscope and made detailed
drawings
Electron Microscopes
• made in the 1940’s, uses electron
beams instead of light
•Allows more detail, but specimens
are usually killed in the staining
process
•Two types:
•TEM: beam goes through
specimen
•SEM: scans surface only
1. The ___ of a microscope in an increase in the detail shown
in the specimen.
a. fragmentation
b. magnification
c. resolution
2.What part of the microscope holds the ocular lens?
a. eyepiece
b. nosepiece
c. stage
3.A lens which has 100 X written on it would be the ___
lens.
a. eyepiece lens
b. high power
c. low power
4.The ___ allows light to pass through the specimen.
a. diaphragm
b. eyepiece
c. ocular opening
5.To find the total magnification for a microscope, you
would ___ the power on the ocular lens and the power of
the objective lens.
a. add together
b. divide
c. multiply