microscopy

Question 1

main parts of light microscope

Answer 1

from eye:
eyepiece lens
objective lens
(specimen)
condenser
light source

Question 2

numerical apertur equation

Answer 2

nsinø

Question 3

types of light microscopy

Answer 3

bright field - can be done while cell is alive
phase contrast - more detail
dark feel - rays of light directed from the side, only scattered light reaches cell

Question 4

purpose of cell staining

Answer 4

enhance contrast in light microscopy
some wavelengths absorbed some pass through –> coloured image

Question 5

how does immunostaining work

Answer 5

antibodies coupled with fluorescent probes specifically bind to targets

used to image a specific part of the cell

Question 6

confocal microscopy

Answer 6

used to obtain very sharp images
laser used to illuminate small pinhole

can be used to create 3D images by stacking

Question 7

what is atomic force microscopy

Answer 7

probe microscopy, pulling proteins

Question 8

what is the green fluorescent protein used for

Answer 8

found naturally occurring in marine organism
makes a fusion protein to get intrinsically fluorescent protein produced in cell

Question 9

electron microscopy pros and cons

Answer 9

beyond diffraction limit
under vacuum so cells are dead and dehydrated (often lost structure)
difficult prep

Question 10

cryo electron microscopy often used to

Answer 10

solve macromolecular structures
eg. image virus

Question 11

light microscopy can image up to a resolution of…

Answer 11

0.25um

Question 12

electron microscopy can image down to

Answer 12

1nm