Analysis of cell components

Question 1

Magnification

Answer 1

• size of image / size of real object

- how much bigger the image is than the specimen

Question 2

resolution

Answer 2

• how detailed image is

- how well a microscope distinguishes between 2 points that are close together

Question 3

oprical (light) microscope

Answer 3

• light to form an image
• max res 0.3 micrometers
• cant use to view smaller organelles than 0.2
• max magnification x1500

Question 4

electron microscope

Answer 4

• use electrons to from an image
• higher res so give more detailed image
• max res is 0.0002 micrometers
• max magnification x 1500000
• produces black and white image but can be coloured by a computer

Question 5

transmission electron microscopes

Answer 5

• use electromagnets to focus a beam of electrons so transmitted through the specimen
• denser parts absorb more electrons so makes them look darker on the image
• higher res image so you see internal structures of organelles
• view specimen in a vacuum no good for living organisms
• only on thin specimens

Question 6

Scanning electron microscopes

Answer 6

• can beam of electrons across the specimen
• knock off electrons from specimen gathered in a cathode ray tube to form an image
• images show surface of specimen and be 3D
• used on thick specimens
• lower res the TEMs