Magnification Flashcards Preview

AS/A2 BIOLOGY > Magnification > Flashcards

Flashcards in Magnification Deck (8)
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1
Q

What is the difference between magnification and resolution?

A

Magnification- how large the image is compared to real life.

Resolution- the smallest distance below which 2 discreet point will be see as one.

2
Q

What is the formula for magnification?

A

m=o/a (observed/actual size)

3
Q

What are the advantages of the light microscope?

A

1) Inexpensive
2) View a variety of samples
3) Easy to use

4
Q

What are the disadvantages of the light microscope?

A

1) All specimens require preparation (staining)

2) Poor resolution

5
Q

What are the advantages of the electron microscope?

A

1) Greater magnification

2) Greater resolution (lower wavelength of electrons)

6
Q

What are the disadvantages of the electron microscope?

A

1) Specimens has to be dead
2) Samples must be placed in a vacuum as electrons may be deflected in the air.
3) Very expensive
4) Require a lot of skill to use

7
Q

What are the steps to calculate magnification when a scale bar is involved?

A

1) Use a ruler to measure the length of the scale bar
2) Convert measurement into the same units of the scale bar
3) Divide the image scale bar length by actual scale bar length

8
Q

How do you calculate actual size when a scale bar is involved?

A

1) Measure the length of the specimen in millimetres (a)
2) Measure the length of the scale bar in (millimetres) (b)
3) Divide (a)/(b)
4) Multiply answer by scale bar units.