Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Exam 2 > Flashcards

Exam 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

How do you prepare a smear

A
  1. aseptically a thin film of a specimen is spread on a slide
  2. Film is air dried
  3. then heat fixed (adhere and kills things on slide)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is staining?

A

procedure that use dyes to add color to microbes or cellular structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are dyes?

A

chemicals added to microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are basic dyes?

A

have positivity charged ions that help them adhere to negatively charged bacteria
Ex. Crystal Violet, Methylene Blue, and Safranin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are acidic dyes?

A

have negative charged ions that are attracted to background
bacteria appears colorless against a stained background
Ex. Nigrosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a simple stain?

A

use 1 dye

determine shape and arrangement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is differential stain

A

places bacteria into categories

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are special stains?

A

stains specific part of microbes

Ex. ENDOSPORE STAIN, Negative Stain, and Flagellar Stain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how do you make a gram stain?

A
  1. make smear
  2. Crystal Violet –> 1 min
  3. Rinse with water
  4. Iodine –> 1 min
  5. Decolorize with ethyl alcohol
  6. rinse with water
  7. Safarrin –> 1 min
    8 rinse with water
  8. blot dry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Gram positive bacteria appears

Why?

A

purple
Ex. bacillus
have many peptiodglycan and they retain primary dye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

gram negative bacteria appears

why?

A

red/pink
Ex. E. Coli
have few peptidoglycan that allow decolorization of primary dye and adherance to the counterstain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how do you make an acid fast stain?

A
  1. make smear
  2. carbolfucshin –> microwave –> 1 min
  3. cool and decolorize with acid alcohol
  4. rinse with water
  5. methylene blue – 30 seconds
  6. rinse with water
  7. blot dry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Acid Fast positive bacteria appears

why?

A

bright red
waxy material called mycolic acid
Once heated carbolfuchsin are applied and not decolorized with alcohol and appear read

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Acid Fast negative bacteria appears

whY?

A

blue

if bacteria doesnt contain mycolic acid carbolfuchsin is decolorized with acid alcohol and methylene blue adheres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the steps for endospore stain?

A
  1. make smear
  2. Malachite green –> microwave –> 1 min
  3. cool rinse with water
  4. Safranin –> 45 seconds
  5. Rinse with water
  6. blot dry
    * view on oil immersion lens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the results of spore stain?

A

if spore present –> green ( can be inside or out of cell)
bacteria cell –> red
Ex. of positive Bacillus and Clostridum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the reasons for the spore stain results?

A

spore are resistant to mild heat but heating in the microwave allows them to open –> absorb malicite green stain

bacteria cells are decolorized with water and counter stain adheres (red) to cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the steps for a negative stain?

A
  1. mix bacteria with Nigrosin on one end of slide
  2. Use second slide, spread suspension over entire slide
  3. Air dry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the results for Negative Stain?

A

used to determine capsules (structures that surround cell wall)

if capsule is not present it wont accept the stain and will appear as light spots against a dark background

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

prokaryotic characteristics

A 
DNA not in a membrane (no nucleous)
very small
cell wall have peptidoglycan
no membrane bound organelles
Ex. bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

eukaryotic characteristics

A 
DNA in a membrane (nucleous)
larger and more complex
not all have cell wall bu most
membrane bound organelles
Ex. Human, plant , and fungi
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are some similarities in prokaryotic and eukaryotic cells?

A

contain carbohydrates, protein, lipids, and nucleic acids
use chemical reaction to metabolize food build protien and store energy
contain cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the size of prokaryotes?

A

0.1 um ( 10 ^ -6) to 50 um in diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

why is the size significant in prokaryotes?

A

all less space and food so can reproduce and adapt quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is coccus shape?

A

spherical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is bacillus shape?

A

rod

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is spirillum shape?

A

spiral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is the plemorphic shape?

A

many shapes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is strepto shape?

A

chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the staphylo shape?

A

grape- like clusters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is the diplo shape?

A

two (pair)

32
Q

what is tetrad shape?

A

group of four

33
Q

what is flagellum?

A

structure used for motility

34
Q

what are monotrichous?

A

one flagellum at one end

35
Q

what is amiphitrichous?

A

one flagellum on each end

36
Q

what is lophotrichous?

A

turf of flagella at one or more ends

37
Q

what is peritrichous?

A

flagella around entire surface

38
Q

what is the movement of using flagellum?
run
tumble

A

rotation of flagella is clockwise or counterclockwise
move in one direction
stop and change directions

39
Q

what is taxis?
positive
negative

A

movement toward or away from a stimulus
towards
away

40
Q

what is chemotaxis?

A

movement involving chemical

41
Q

what is phototaxis?

A

movement involving light

42
Q

what is geotaxis?

A

movement involving gravity

43
Q

what is fimbriae?

A

appendage that is shorter and straighter thatn glagella
2 to 100’s per cell
used for attachement

44
Q

what is pili?

A

longer than fimbriae
1 to 2 per cell
used in conjugation

45
Q

what is glycocalyx?

A

made of polysaccharides
found outside cell well
cell protection

46
Q

what are types of glycocalyx?

A

capsule

sime layer

47
Q

what is a capsule?

A

glycocalyx firmly attached to cell wall

protects bacteria from phagocytosis

48
Q

what is slime layer?

A

glycocalyx loosely attached to cell wall

protects from water loss

49
Q

what is the prokarytoic cell wall like?

A

semiridgid structures outside cell membrane

50
Q

what is the function of prokaryotic cell wall?

A

protection and give shape

51
Q

what are things to know aobut prokaryotic cell walls?

A

can only be seen clearly with an electron microscope

site where many antibiotics damage bacteria

52
Q

what is peptidoglycan?

A 
main component of cell wall
it contains 2 monosaccharides
NAG ( N-acetylglucosamines)
NAM ( N-acetylmuramic)
amino acid for crossbridge
53
Q

what is gram positive cell wall consist of?

A

25 - 30 layers of peptidoglycan

teichoic acid

54
Q

what is teichoic acid?

A

acidic polysaccharide
give cell surgace a negative charge
prevents lyse

55
Q

what is the gram negative cell wall consist of?

A

10 layers of peptidoglycan
no teichoic acid
contain additional wall layer called LPS outside peptidoglycan

56
Q

what is LPS?

A

LipoPolySaccharide

layer is toxic to humans, is responsible for symptoms of infections and is resistant to many antibiotics

57
Q

what is the cell membrane?

A

structure below cell wall

forms a phospholipid bilayer similar to eukaryotic cells

58
Q

what is the function of cell membrane?

A

acts as selective barrier

site of ATP production

59
Q

What is simple diffusion ?

A

movement of molecules from areas of high to low

60
Q

what is osmosis?

A

diffusion of water across cell membrane high to low

61
Q

what is a solute?

A

substance dissolved in a solvent

Ex. salt

62
Q

what is a solvent

A

a liquid

Ex. water

63
Q

what is solution

A

mixture of the two or more substance

Ex. Salt water

64
Q

lower concentration of solutes ouside the wall would be?

A

hypotonic solution

65
Q

what does hypotonic solution consist of?

A

higher concentration of water outside celle
water moves into the cell
Lysis could happen

66
Q

higher concentration of solutes outside the cell is?

A

hypertonic

67
Q

what does a hypertonic solution consist of?

A

higher concentration of water inside the cell
water moves out
crenation could happen

68
Q

what is isotonic solution?

A

equal concentration of both solutes

cells remain intact

69
Q

what is cytoplasm?

A

jelly-like substance found inside cell
80% is water
contains carb., proteins, lipids, and genetic material

70
Q

what is a nucleoid?

A

cluster of genetic material

71
Q

what are ribosomes?

A

structures directs protein synthesis
composed of 2 sub units
smaller than eukaryotic
very numerous in cells that are actively growing

72
Q

what are inclusions?

A 
large storage molecules made of
C
N
S 
P
formed when these elements are abundant
not always present
73
Q

what are endospore?

A

structure formed when nutrient are limited
contain thick cell walls
able to survive extreme environments conditions
(heat, lack of water, or exposure to chemicals)
can live for 25 million years

74
Q

what happens to endospores when conditions are favorable again?

A

convert back to vegetative state

75
Q

what is sporulation?

A

process of making spores

76
Q

who has spores?

A

bacillus and clostridium

77
Q

how are spores killed?

A

autoclave –> heat under pressure for 20 min

Microbiology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions