4.1.1.5 microscopy

Question 1

What is a ‘stereo’ microscope

Answer 1

An old microscope

Question 2

State characteristics of light microscopes

Answer 2

• small and easy to buy
  -cheap to use
  -simple to use
  -living samples can be used
  -sample can be in colour

Question 3

State characteristics of electron microscopes

Answer 3

-very high magnification
-samples are dead
-viewed only in black and white
-very big microscopes
-very expensive
-samples placed in a vacuum

Question 4

Why may you start with the smallest magnification first when using a microscope.

Answer 4

As it is easy to focus.

Question 5

State how to zoom and focus correctly when using the objective lens.

Answer 5

Move the objective lens until is nearly touches the slide- caution, watch from side to ensure the slide doesn’t get broken. Move the objective lens away from the slide to focus and zoom. Ribosomes are too small to see.

Question 6

How to work out total magnification.

Answer 6

Total magnification = objective magnification x eye Pièce magnification

Question 7

How to work out magnification

Answer 7

Magnification = image height (size) / object height (actual length)

Question 8

How to work out image height (size)?

Answer 8

Image height (size) = Magnification x object height (actual length)

Question 9

How to work out object height (actual length)

Answer 9

Object height (actual length) = image height (size) / magnification