Ch. 3

Question 0

Darkfield

Answer 0

uses condenser, light reflected by specimen enters objective lens, specimen against dark background. look @ LIVING microo that are not visible in brightfield

Question 1

Brightfield

Answer 1

uses visible light against bright background, easy/cheap. observe STAINED specimen, can’t see small things like virus

Question 2

Phase-contrast

Answer 2

use condenser, direct&reflected/diffracted rays together produce image, no staining. to see INTERNAL structure of LIVING specimens

Question 3

Fluorescence

Answer 3

uses UV that causes fluorescent cmpds in specimen to emit light. to find microbes in tissues/specimens fast

Question 4

Confocal

Answer 4

single photon to see one plane @ a time. 2/3-D images of cells

Question 5

TEM

Answer 5

beam of e- pass thru specimen, 2-D. look @ virus/internal ultrastructure in thin sxns of cells

Question 6

SEM

Answer 6

beam of e- reflected frm specimen, 3-D. to study SURFACE features of cells & viruses