The Microscope

A Microscopic History

1590 - Hans and Zaccharias Janssen discovered that lenses in a

tube made objects appear much larger.

1609 - Galileo created a better instrument that could focus.

1674 - Anton Van Leeuwenhoek builds an even better microscope

and is the first to see bacteria.

Anton Van Leeuwenhoek

The Microscope

Parts and Functions

Labeling the Microscope

A

The Eyepiece

• A lens that magnifies the image made by the

objective lens.

B

Coarse Adjustment Knob

• moves the body tube up and down to focus the

image

C

Fine Adjustment Knob

• used to make fine movements of the body tube

to sharpen the image

DObjective Lenses

• These are the lenses that provide for the magnification of the image.

• There is a high powered lens and a low powered lensthat are held on a turret or nosepiece.

E

The Stage

• This is where the slide is held so that it can be viewed.

• There are stage clips on the stage that hold the slide

in place.

F

The Arm

• This supports the body tube.

• One hand must be placed here to carry the

microscope.

GThe Base

• Supports the microscope

• When moving the microscope, one hand must

be underneath the base.

HThe Mirror

• This directs light up through the hole in the

stage (diaphragm) through the slide and the

objective lenses.

The Diaphragm

• Controls the amount of light that passes

through the slide and lenses.

• Can be twisted to increase or decrease the

width of its opening

Terms

Power of Magnification

• The relative enlargement of an specimen seen

through a microscope.

• Can be calculated - Power of the Eyepiece Lens X

Power of the Objective Lens

Inversion

• An image appears upside down through the

eyepiece.

• When the slide is moved to the right, it appears

in the eyepiece to move to the left.

• When the slide is moved upwards on the stage,

it appears to move to the bottom of the view.

Working Distance

• The distance between the objective lens and

the glass slide.

• The higher the magnification, the less distance

between the two.

Field of Vision

• The surface area of the slide that can be seen

through the microscope.

• This decreases with increased magnification.

Other Tools of the Scientist

1) Petri Dish 6) Slide and Coverslip

2) Safety Goggles 7) Beaker

3) Erlenmeyer Flask 8) Probe

4) Bunsen Burner 9) Dropper

5) Test Tube Clamp 10) Scalpel

11) Mortar and Pestle

Petri Dish

Used to grow bacteria in. It is filled with a gel-like substance called agar and bacteria cells are scraped onto it and left to grow.

Bunsen Burner

Used in the laboratory to burn or heat items.

Beaker

A glass cylinder used to measure quantities of liquids and mix solutions.

Erlenmeyer Flask

A glass container used for measuring and mixing chemicals.

Mortar & Pestle

A ceramic or marble instrument used to crush substances into a finer form.

Scalpel

A type of knife used to cut into tissues in the lab. Many different blades have many specific jobs.

Dropper

Used to measure small amounts of liquid. Can be used for preparing slides for the microscope.

Safety GogglesUsed to improve your appearance in the lab. (Umm…No!)Used to protect your eyes from harmful chemicals, substances, etc…

Slide and Cover Slip

Used to mount cells for viewing under the microscope.

Test Tube Holder

Used to hold test tubes that contain hazardous chemicals and hot substances.