Microscopes Flashcards
What is a microscope?
Piece of equipment which when looked through magnifies whatever’s is underneath it.
What does a light microscope use to magnify objects?
Light
What does an electron microscope use to view an object?
Electrons
What’s the greatest possible magnification for a light microscope
X2000
How much can an electron microscope magnify by?
X1000000000 1 million
Which microscope would you use to see objects in cells more clearly and in far more detail?
Electron microscope rather than light microscope
How do you calculate magnification
Magnification (M) = image size (I)
————–
Real size (R)
When your calculating magnification the image size must be in the units…
Millimetres mm
A bacterium is viewed under a light microscope using a X40 objective and a X10 eyepiece. The image is 1.2 mm long. Calculate the actual length of the cell.
Magnification = 40 X 10 = X400
Image= 1.2 mm = 1200 um so actual length of cell = 1200/400=3um
1mm=
1000 um
What determines how good a microscope is at showing small details?
Resolution
The development of the electron microscope had allowed us to…
See smaller things in better detail
What are the 5 pieces on a microscope?
Eyepiece lens Objective lens Slide Stage Focusing wheel
Where is the eyepiece lens?
What you put your eye to
Where is the objective lens
The lens where what ever your magnifying is underneath it
Where’s the stage
The thing the slide is on
Where’s the slide
What is out on the stage underneath the objective lens
Where’s the focusing wheels
Fine focusing wheel is above the coarse focusing wheel
What is the resolution of the microscope
The resolution of a microscope is the minimum distance between two points that can still be seen as two points rather than one point
State two reasons why an electron microscope can detect more detail inside a cell, compared with a light microscope
Electron microscope has a greater/higher magnification. And it also has a better/greater resolution
What do you measure small things with
Millimetres
Micrometers
Manometers
Picometres
How do you get from millimetres to micrometers
Divide by 1000
Micrometers to manometers
Divide by 1000
Manometers to picometres
Divide by 1000
