1 Cells - Microscopy

Question 1

What are the different types of microscope?

Answer 1

• light microscope/ optical microscope
• Transmission electron microscope
• Scanning electron microscope

Question 2

How does a light microscope work?

Answer 2

• uses a beam of light to create larger and more detailed images

Question 3

How many times can a light microscope magnify?

Answer 3

up to x1500, cannot view small organelles such as ribosomes as they are smaller than the wavelength of light so they are not visible in the image created

Question 4

What sort of organisms can the light microscope produce images of?

Answer 4

• living organisms
• must be very thin
• requires staining

Question 5

What are the cons of a light microscope?

Answer 5

• Low resolution
• cannot view small organelles

Question 6

What are the pros of a light microscope?

Answer 6

• able to view living organisms
• inexpensive

Question 7

How do electron microscopes work?

Answer 7

Using beams of electrons instead of light, they have a smaller wavelength and therefore electron microscopes have a higher resolution and magnification. However, they require vacuums in order to function so that particles do not interfere, this also means that the specimens must be dead.

Question 8

How does a transmission electron microscope work?

Answer 8

• beams of electrons are fired at the thin sample
• allows the samples with a thin cross section to be viewed in high resolution, this is good for learning about internal structures

Question 9

How does a scanning electron microscope work?

Answer 9

• Focused beam of electrons reflect of the surfaces of structures
• this creates a 3D image
• samples do not need to be thin