Exam 1 Flashcards
Cell
smallest functional unit of life
Robert Hooke
Experimental curator in 1665 - looked at cork cells and coined the term cell after monastery cells
Antoni van Leuwenhoek
1670s - made glass lenses for microscope- approx. 200x magnification (one lens) 1st to see living cells
Cell theory
- all organisms consist of one or many cells
- cells are the basic unit of all organisms
- all cells come from preexisting cells
Eduard Strasbuger
1880 - drew time lapse observations of a a cell dividing
Microscopy goal
Decipher the underlying principles that govern the structure and activity of a cell
Powers of Microscopy
magnification and resolution
Magnification
ability to make an object appear larger
resolution
ability to distinguish two objects from each other (as being separate)
Resolution equation
d = (0.5wavelength)/nsin theta)
n sin theta
numerical aperature
denominator of resolution equation
Ways to increase resolution
need to make d smaller, so decrease wavelength or increase theta or n
n of resolution equation
reflective index of medium you are using
air=1
oil=1.5
water = 1.3
condensor
focuses field on microscope
light microscopy
bright-light microscopy
see dead or alive cells
stained light micrographys
fix and stain cells (killing them)
need to have controls
bright-field microscopy
simple light microscopy
phase contrast microscopy
variation of light microscopy with dark shadows
differential interference contrast (DIC)
light from bottom and sides of light microscopy
fluorescence microscopy
excitation and emission
uses different wave lengths
need fluorescence like GFP
fluorescent probes
uses light such as green and red
