Microbiology Ch 3 - Microscopy And Cell Structure

Front 1

The ability to see the microbial world is dependent on the __________ __________ of your instument

Back 1

resolving power

Front 2

Resolving power

Back 2

the minimum distance that can exist between tow objects when those objects can still be observed as seperate entities.

Front 3

limitation of resolving power include:
1.
2.
3.

Back 3

1. lens
2. magnification
3. wavelength of light

Front 4

Light microscopes use _______ for imaging

Back 4

light

Front 5

brightfield

Back 5

use oil to displace air between objective and sample (prevents bending of light or refraction)

Front 6

phase contrast

Back 6

denser material appears darker due to differences in refraction of light between the medium and sample

Front 7

Interference

Back 7

like a phase contrast , yields a 3D image.

Front 8

Dark

Back 8

angled light makes objects stand out against a dark background

Front 9

Fluorescence Microscope

Back 9

used to observe cells that have been tagged or stained with fluorescent materials. Use ultraviolet light to observe.

Front 10

_________ __________ use elctrons which have a shorter wavelength that increase the resolution 1000x better than light microscopes. Need a ________

Back 10

electron microscope
vacuum

Front 11

- the density of the sample will determine if the electrons go through and are imaged on film.
uses thin sectionted samples

Back 11

transmission

Front 12

-coat specimen with metal
-electrons are reflected back to viewing chamber
-good for large specimens

Back 12

scanning electron

Front 13

-allow us to better visualize whole cells or specific parts of cells.
-used in identification of organisms
-use fixed or attached cells on a slide

Back 13

dyes and staining

Front 14

impart color to the cells

Back 14

simple stains

Front 15

have a positive charge sot hey are attracted to the negatively charged parts (nucleic acids and proteins

Back 15

basic dyes

Hint 15

Examples:
methylene blue
crystal violet
safranin

Front 16

used to create a colored background against which colorless cells can be seen (negative staining)

Back 16

acid dyes

Hint 16

Example:
India Ink to stain capsules

Front 17

used to distinguish one group of bacteria from another

Back 17

differential stains

Front 18

distinguishes between gram positive and gram negative bacteria

Back 18

gram stain

Front 19

Gram Stain
1.
2.
3.
4.

Back 19

1. add crystal violet, wash
2. add Gran's iodine, stabilizes the crystal violet
3. add 95% ethanol
4.counter stain with safranin

Hint 19

3. tis decolorizes Gram-negative bacteria not the Gram-positive

Front 20

Gram-________ bacteria are violet

Back 20

postitive

Front 21

Gram-________ bacteria are red

Back 21

negative

Front 22

Acid-Fast stain is ued to detect ______________

Back 22

mycobacterium

Front 23

_____________ retain the primary stain ______ _____, with heat, while all of the other cell are blue from the counter stain

Back 23

mycobacterium

carbol fuchin

Front 24

use India ink as a negative stain

Back 24

capsule stain

Front 25

malachite green

Back 25

endospore stain

Front 26

use a mordant

Back 26

flagella stain

Front 27

coccus

Back 27

spherical shaped

Front 28

bacillus

Back 28

rod shaped

Front 29

coccobacillus

Back 29

short rod shaped

Front 30

vibrio

Back 30

curved rod shaped

Front 31

spirochete

Back 31

helical shaped

Front 32

arrangements

Back 32

formed after cell division

Front 33

diplococci

Back 33

pairs of cocci

Front 34

chains

Back 34

streptococci

Front 35

clusters

Back 35

staphylococci

Front 36

Prokaryotic Cell Structure must accomplish the following:

Essential

Back 36

1. enclosure
2. replication
3. synthesis of cell components
4, generation and storage of energy compounds
5. entry and exit of specific molecules

Front 37

Prokaryotic Cell Structure must accomplish the following:

Non-Essential

Back 37

1. cell movement
2. genetic transfer of material
3. storage of reserve material
4. form endospores

Front 38

cytoplasmic membrane

Back 38

thin fluid structure that surrounds the cytoplasm and acts as a semi-permeable barrier to the external environment

Front 39

cytoplasmic membrane

Back 39

- phospholipid bilayer and the fluid mosaic model
- embedded proteins (receptors)
- site of elctron transport in the tranformation of energy

Front 40

diffusion

Back 40

no energy input

Front 41

simple diffusion

Back 41

small hydrophobic molecues that move freely across the membrane

Front 42

facilitated diffusion

Back 42

- passive transport of molecules across a concentration gradient
- from higher to lower concentration

Front 43

osmosis

Back 43

the flow of water based on the concentration of water and solute particles

Front 44

hypertonic solution

Back 44

higher solute concentration outside the cell

Front 45

hypotonic solution

Back 45

higher solute concentration inside the cell

Front 46

active transport

Back 46

uses energy to facilitate the transport of molecules

Front 47

proton motive force

Back 47

association of movemnt of a substance with the movement of a proton

Front 48

symporter

Back 48

molecule and proton enter cell together

Front 49

antiporter

Back 49

as molecure enters cell, a proton leaves

Front 50

uniporter

Back 50

a single substance enters

Front 51

transport systems that use ATP

Back 51

- when concentrate of solute particle is higher inside the cell
- utilize specific receptor molecules and the input of energy (ATP)

Front 52

Cell enclosure of prokaryotes

Back 52

1. cytoplasmic membrane
2. cell wall
3. outer membrane (gram negative bacteria)

Front 53

prokaryotic cell wall

Back 53

- unique
- rigid structure which determines shape
- holds cell together and prevents ruputre
- often the cause of disease
- often where antibiotic work
- accounts for differential Gram staining

Front 54

petidoglycan

Back 54

- macromolecure found in bacteria
- made of alternating subunits
- NAM
- NAG