Using the Microscope and the Metric System

Vocabulary flashcards covering microscope parts, their functions, magnification concepts, parfocality, working distance, field of view, and key metric system concepts from the notes.

Arm facing out (storing a microscope)

When storing, keep the microscope’s arm facing outward so it’s easy to grab and to protect the instrument.

Cord not wrapped around the base

Do not wrap the power cord around the base when storing to prevent damage and tangling.

Correct storage slot

Place the microscope in its correct storage slot to prevent movement and damage.

Scanning objective in place

Set the objective to scanning (4x) before viewing to locate specimens and maximize working distance.

Stage all the way down

Lower the stage completely before sliding slides in or out.

Ocular lens

Eyepiece through which you view the specimen; commonly 10x magnification.

Head

Upper part of the microscope that houses the oculars and connects to the nosepiece.

Revolving nosepiece

Rotating turret that holds multiple objective lenses.

Objective lens

Lenses near the slide that determine magnification (examples: 4x, 10x, 40x).

Arm

Supports the microscope and provides a handle for carrying; connects to the base.

Stage

Flat platform where the slide rests; may have clips or a mechanical stage.

Condenser

Lens system under the stage that concentrates light on the specimen.

Iris diaphragm lever

Controls the aperture size of the iris diaphragm to adjust light intensity and contrast.

Substage light

Light source beneath the stage that illuminates the specimen.

Fine adjustment knob

Small knob used for precise focusing after coarse adjustment.

Coarse adjustment knob

Large knob used to bring the object into general focus, especially at scanning or low power.

Base

Bottom support of the microscope; provides stability and sometimes houses parts of the illumination system.

Light control

Dial or switch to adjust the brightness of the illumination.

Magnification

Process by which an image appears larger than its actual size.

Resolution

Crispness of the image; the ability to distinguish two adjacent points as separate.

Total magnification

Product of the ocular magnification and the objective magnification.

Parfocal

Property that allows the image to stay in focus when switching objectives, needing mostly fine focus.

Working distance

Distance between the objective lens and the slide; longest at scanning power and decreases with higher magnification.

Field of view

The visible area seen through the eyepiece; decreases as magnification increases.

Scanning power

4x objective with 10x ocular = 40x total magnification; provides the largest field of view and longest working distance.

Low power

10x objective with 10x ocular = 100x total magnification; intermediate field of view.

High power

40x objective with 10x ocular = 400x total magnification; smallest field of view.

Base units (Metric system)

Standard units for length, volume, and mass: meter, liter, and gram.

Meter

Base unit of length in the metric system; 1 meter = 100 centimeters.

Liter

Base unit of volume in the metric system; 1 liter = 1000 milliliters.

Gram

Base unit of mass in the metric system; 1 gram = 1000 milligrams.

Millimeter

Smallest primary division on many rulers; 1 millimeter = 0.001 meters.

Metric prefixes

Kilo (10^3), Hecto (10^2), Deka (10^1), Base (10^0), Deci (10^-1), Centi (10^-2), Milli (10^-3), Micro (10^-6).

Conversion rule (smaller to larger units)

Move the decimal point to the left (exponent becomes more negative).

Conversion rule (larger to smaller units)

Move the decimal point to the right (exponent becomes more positive).

Convert 5 meters to centimeters

5 meters = 500 centimeters.

Convert 5 decimeters to kilometers

5 decimeters = 0.0005 kilometers.