Microscopes

Question 1

What are the three types of microscopes?

Answer 1

Light/ optical microscopes
Transmitting electron microscope (TEM)
Scanning electron microscope (SEM)

Question 2

What is resolution?

Answer 2

the ability to distinguish between two points

Question 3

What are the limitations and advantages of a light microscope?

Answer 3

limitations: low resolution due to long wavelength, low magnification
ads: uses living specimens see processes taking place, true colour

Question 4

What are the limitations and advantages of a transmitting electron microscope?

Answer 4

limitations: thin specimen required, artefacts may be introduced, specimens must be dead, black and white images formed
ads: high resolution images, internal structures viewed

Question 5

What are the limitations and advantages of a scanning electron microscope?

Answer 5

limitations: specimens must be dead, black and white image formed, lower resolution than a transmitting electron microscope
ads: thick external structures viewed, 3d images produced

Question 6

Facts about light microscopes?

Answer 6

small and easy to carry
no vacuum needed
easy sample prep
up to 2,000x magnification
resolution 200nm
specimens can be living or dead

Question 7

Facts about electron microscopes?

Answer 7

large and installation means it can’t be moved
vacuum needed
complicated sample prep
over 500,000x magnification
resolution 0.5nm
specimens are dead

Question 8

What is the magnification equation?

Answer 8

magnification = image/actual