Ch 1 Microscopes and Staining

Question 1

Hans Janssen and son Zacharias Janssen

Answer 1

invented first compound microscope in 1590

Question 2

Galileo Galilei

Answer 2

developed occhiolino or compound microscope with a convex and a concave lens

Question 3

Anton van Leewenhoek

Answer 3

-credited for bringing microscope to the attn. of biologist, even though lenseswere already being produced in the 1500s

Question 4

What type of microscope generally used?

Answer 4

• Compound, bright-field microscope

- Watson “Service” developed in early 1900s

Question 5

phase contrast M

• interference microscope
• differential interference microscope

Answer 5

examine unstained cells and tissues still living

• quantification of tiss mass
• assessing surface properties of cells

Question 6

Dark-field M

Answer 6

• only light that’s been scattered or diffracted by structures in spec reaches objective
• useful in examining autoradiographs

Question 7

Flourescence

Answer 7

• makes use of ability of certain molecules to fluoresce under UV light
• various filters used

Question 8

Confocal M

Answer 8

to visualize in very thin optical sections, like optical dissection

Question 9

UV M

Answer 9

• detecting nucleic acids and proteins

- uses quartz lens with UV light source

Question 10

Polarizing M

Answer 10

• highly ordered molecules or arrays of molecules can rotate angle of plane of polarized light, seeing birefringence (double refraction)
• striated muscle, testicular interstitial cells

Question 11

Electron M

• TEM
• SEM

Answer 11

• like light M, but using e-
  
  • those e- passed, lighter than those absorbed or scattered.
  • freeze fracture

-e- beam doesn’t pass through specimen but is scanned across surface