chapter 3 Flashcards Preview

Microbiology > chapter 3 > Flashcards

Flashcards in chapter 3 Deck (20):
1

what are the units of microscopes in order?

mm --> um --> nm goes over three decimal places to left each

2

what are uses for compound light microscopes

stained or live specimens and count microbes

3

what ocular lens do?

to view it is 10x magnification

4

what does illuminator do?

light source

5

what is the condenser do?

focuses light

6

what are the objective lens?

to magnify
4x
10x
40x
100x

7

what is the total magnification?

objective x ocular

8

what is the features of phase contrast microscope?

special condenser that improves contrast
between specimen and surrounding medium

9

what are the uses of phase contrast microscopes?

live, unstained specimens; internal structure
motility, size, and shape

10

what are the features of darkfield microscopes?

uses darkfield condenser
specimen appears light against black backgroudn

11

what are the uses of darkfield microscopes

living microbes that are invisible in bightfield

12

what are the features of fluorescence microscope?

UV light to illuminate fluorescent microbes

13

what are the uses of fluorescence microscope?

Antibody research to identify microbes

14

what are the uses of electron microscope?

uses beam of electrons focused by electromagnetic lenses
specimen are pretreated with chemical or dyes
specimen are dead

15

what are the uses of electron microscope?

detained internal and external structures
viewing viruses

16

what are the types of electron microscopes?

scanning (SEM)
transmission (TEM)

17

what doe SEM feature?

detailed 3D images
whole cells are coated with gold, an electron beam passes over cells, electrons are scattered
objects are magnified 1000 t 10000 times

18

what are the uses for SEM?

detailed external features
viewing viruses

19

what are the features of TEM?

ultrathin section of specimen are cute
section are treated with lead
beam of electrons passes through section
objects are magnified 10000 to 100000 times

20

what are the uses of TEM?

detailed internal structures
viewing viruses