Topic 2 Microscopes

Question 1

What are the differences between optical and electron microscopes in terms of illumination

Answer 1

O. Illuminated by visible, ultraviolet or laser light that is focused on the specimen through lenses.
E. An electron beam that is focused by electromagnets on the specimen creates illumination

Question 2

What are the differences between optical and electron microscopes in resolution and magnification

Answer 2

Optical microscopes operate at lower levels of resolution and magnification which electron microscopes at higher levels

Question 3

What are the differences between optical and electron microscopes in terms of the image

Answer 3

O. Coloured

E. Black and white

Question 4

What are the differences between optical and electron microscopes in terms of living dead

Answer 4

O. Can be used to view living cells

E. Can’t ask they put the specimen through non life supporting conditions

Question 5

What is the difference between scanning and transmission microscopes

Answer 5

SEM: reveal surface detail and texture through an electronic beam which interacts with the bulk surface of a specimen.
TEM: reveal fine detail of cell ultra structure through the use of a focused electron beam which passes through an ultra thin slice of a cell.

Question 6

What is the difference between magnification and resolution

Answer 6

Magnification. Process of enlarging something only in appearance, not in size; the ratio of the size of the image as viewed through the microscope to the size of the object

Resolution: the ability to see two points that are close together as separate entities