Microscopes Flashcards
Name two types of microscope
•light electron
•electron microscope
Define magnification
The number of times larger an image is compared with the real size of the object
Name the lenses in a light microscope
Objective lens
Eyepiece lens
What is the part of the microscope where you place the specimen on in a light microscope?
The stage
How do you find the actual size of an object when given the magnification?
Actual size= Image size / magnification
Define resolution?
The ability to distinguish between two separate points.
Resolution of human eye = 0.3mm
What is cell theory?
1) all organisms are composed of one or more cells
2) The cell is the basic organisational unit of life
3) all cells arise from pre existing life
Limitations of light microscopes:
Low magnification
Low resolution
Limitations of electron microscopes:
A vacuum is required so no living cells can be observed
Inability to see colour
Difficult to use
Expensive
Scanning electron microscope limitations:
Expensive
Difficult to use
Vacuum is needed so no living cells can be observed
Advantages of light microscopes:
Easy to use
Shows colour
Cheap
Advantages of transmission electron microscopes and scanning electron microscopes:
Higher resolution
Higher magnification
