Microscope Parts, Functions, and Magnification Calculations for Biology

What is the function of the ocular lens in a microscope?

The ocular lens is used to view the magnified image of the specimen.

What does the mechanical stage of a microscope do?

The mechanical stage allows for precise movement of the slide to view different areas of the specimen.

What is the purpose of the iris diaphragm in a microscope?

The iris diaphragm controls the amount of light that reaches the specimen.

How do you calculate total magnification using an objective lens?

Total magnification = (magnification of ocular lens) x (magnification of objective lens).

What are the three types of objective lenses mentioned?

Scanning power lens (4x), low power lens (10x), high power lens (40x), and oil immersion lens (100x).

What are the four main human body cavities?

Cranial cavity, spinal cavity, thoracic cavity, abdominopelvic cavity

What separates the thoracic cavity from the abdominopelvic cavity?

Diaphragm

What is the anatomical position?

Standing erect, facing forward, upper limbs at sides, palms forward

What is the midsagittal (medial) plane?

A vertical plane that divides the body into left and right halves

What does the transverse plane do?

Divides the body into superior (upper) and inferior (lower) parts

What is the frontal (coronal) plane?

A vertical plane that divides the body into anterior (front) and posterior (back) parts

What are the parts of a compound light microscope?

Ocular lens, objective lenses, stage, coarse focus, fine focus

What should you use to clean microscope lenses?

Lens paper and an alcohol wipe

What is the first step in using a microscope?

Start with the scanning objective (shortest lens)

What is the purpose of adjusting the coarse focus on a microscope?

To make the image visible

When should you use the fine focus on a microscope?

To achieve a clear image after the coarse focus has been adjusted

What is the last step when using a high power objective lens?

Adjust ONLY the fine focus for a clear image

What should you do to center the desired view on a microscope slide?

Adjust the slide using slide controls

Ocular lens

The lens through which the viewer looks to see the magnified image, typically providing a magnification of 10x.

Mechanical stage

A platform that holds the microscope slide in place and allows for precise movement in multiple directions.

Base

The bottom part of the microscope that provides stability and support.

Arm

The part of the microscope that connects the base to the head and supports the optical components.

Nosepiece

The rotating part of the microscope that holds the objective lenses and allows the user to switch between them.

Course focus knob

A knob used to make large adjustments to the focus of the microscope, moving the stage up and down quickly.

Fine focus knob

A knob used for making small adjustments to the focus of the microscope, providing a clearer image.

Stage controllers

Controls that allow the user to move the slide left, right, forward, or backward on the mechanical stage.

Objective lenses

Lenses located on the nosepiece that provide different levels of magnification, typically ranging from 4x to 100x.

Light

The source of illumination for viewing the specimen, often provided by a built-in light or mirror.

Iris diaphragm

A device that regulates the amount of light that reaches the specimen, enhancing contrast and resolution.

Total magnification

The overall magnification of a microscope, calculated by multiplying the magnification of the ocular lens by the magnification of the objective lens.

Total magnification using scanning objective

40x, calculated as 10x (ocular lens) x 4x (scanning objective).

Total magnification using low power objective

100x, calculated as 10x (ocular lens) x 10x (low power objective).

Total magnification using high power objective

400x, calculated as 10x (ocular lens) x 40x (high power objective).

Total magnification using oil immersion lens

1000x, calculated as 10x (ocular lens) x 100x (oil immersion lens).