Microscopy (core practical): Key concepts in biology: Biology: GCSE (9:1)

Light microscope

Equipment which uses visible light to detect and magnify small objects

Magnification

How much an image appears to have increased in size by

Magnification equation

Magnification = size of image/size of real object

Image size

The size of an object on an image after magnification

Actual size

The actual or real size of an object before magnification

Total magnification

The overall magnification in a light microscope due to the combined magnification of the eyepiece lens and the objective lens

Total magnification equation

Total magnification = eyepiece lens magnification x objective lens magnification

Eyepiece lens

The lens that is closest to the eye when viewing a microscope

Objective lenses

A set of lenses above the stage that can be manually adjusted to provide a higher magnification

Magnification scale

A scale bar on an image that represents the actual size of an object

Graticule

A scale with many divisions that is printed on to the eyepiece lens to measure an object's size

Focusing wheel

A twistable wheel that adjusts the focus of an object by changing the height of the microscope stage

Microscope slide

A thin piece of glass that holds biological specimens to be observed under a microscope

Microscope stage

Where the microscope slide is placed and help in place with stage clips

Field of view

The maximum diameter or area that is visible when looking through a microscope eyepiece

Onion cells

An easily obtainable source of plant cells

Cheek cells

An easily obtainable source of animal cells

Iodine solution

An orange-brown dye that can be used to stain onion cells to make them easily observable

Methylene blue

A blue dye that can be used to stain cheek cells to make them easily observable