Bacterial Structure and Function Flashcards
1
Q
Microbe
A
a living organism that requires a microscope to be seen
2
Q
Properties of a microbe
A
- small size
- own genome to replicate
- acquire food and gain energy themselves
- respond to environmental change
- evolve at rapid rates
3
Q
Three domains of life
A
- bacteria
- archaea
- eukarya
4
Q
How are prokaryotes grouped?
A
- bacteria
- archaea
5
Q
How are eukaryotes grouped?
A
eukarya
6
Q
How is eukarya grouped?
A
- algae and plants
- fungi and animals
- protists
7
Q
Prokaryotic nucleus
A
- DNA enclosed within a membrane
- circularly arranged
8
Q
Eukaryotic nucleus
A
- DNA found in nucleus separated from cytoplasm nuclear membrane
9
Q
Prokaryotic histones
A
- DNA not associated with histones
- Other proteins are associated with DNA
10
Q
Eukaryotic histones
A
- DNA is associated with histones and non histone proteins
11
Q
Prokaryotic organelles
A
- none
12
Q
Eukaryotic organelles
A
- multiple membrane enclosed organelles
13
Q
Prokaryotic cell wall
A
- peptidoglycan
14
Q
Eukaryotic organelles
A
- polysaccharide cells walls (cellulose, chitin)
15
Q
Prokaryotic division
A
- binary fission
16
Q
Eukaryotic division
A
- mitosis
17
Q
Bacteria characteristics
A
- prokaryotes
- single cell
- peptidoglycan cell walls
- binary fission
- derive nutrition from organic or inorganic chemicals or photosynthesis
18
Q
Archea characteristics
A
- prokaryotes
- lack peptidoglycan cell wall
- often live in extreme environments
- not associated with any human disease
19
Q
Archea inclues
A
- methanogens
- extreme halophiles
- extreme thermophiles
20
Q
Fungi characteristics
A
- Eukaryotes (distinct nucleus)
- chitin cell wall
- absorb organic chemicals for energy
- yeasts are unicellular
- molds and mushrooms are multicellular
21
Q
Molds
A
consist of masses of mycelia, which are composed of filaments = hyphae
22
Q
Protozoa characteristics
A
- eukaryotes
- absorb or ingest organic chemicals
- may be motile via pseudopods, cilia or flagella
- free living or parasitic
23
Q
Algae characteristics
A
- Eukaryotes
- cellulose cell walls
- found in freshwater, saltwater and soil
- photosynthesis
- produce oxygen and carbohydrates
24
Q
Viruses characteristics
A
- acellular
- DNA or RNA core
- core surrounded by protein coat
- coat may be enclosed in lipid envelope
- replicate only when in living host cell
- inert outside living hosts
25
Bacteriology
study of bacteria
26
Mycology
study of fungi
27
Parasitology
study of protozoa and parasitic worms
28
Virology
study of viruses
29
How are microorganisms measured?
micrometers
| nanometers
30
How many nm are in 1 um?
1000nm
31
Types of light microscopy
- bright field
- dark field
- phase contrast
- DIC
- fluorescence
32
What does light microscopy help see?
size and shape only
33
What does confocal microscopy help see?
Study different structures and how they interact with human cells
34
What does the two-photo microscope help see?
minute details
35
Types of electron microscopy
- SEM
| - TEM
36
Types of scanned probes
- AFM
| - Scanning tunneling
37
Which type of microscope has the largest range?
TEM
38
What type of microscopes can be used within the range of organisms in the book?
- Light
- SEM
- TEM
39
TEM range
10pm - 100um
40
SEM range
10nm - 1 mm
41
light microscope range
200nm - 10nm
42
AFM range
0.1nm - 10nm
43
Steps to prep for light microscopy
- stain
- smear
- fix
44
Staining
- coloring microorganism with a dye that emphasis certain structures
45
Smear
a thin film of a material containing microorganisms spread over a slide
46
Fixation
- microorganisms attached to slide
| - kills them
47
What do stains consist of?
- positive and negative ion
| - one is colored (chromophore)
48
In a basic dye, the chromophore is a what?
cation (+)
49
In an acidic dye, the chromophore is a what?
anion (-)
50
Negative staining
staining the background instead of the cell
51
Types of basic dyes
- crystal violet
- methylene blue
- malachite green
- safranin
52
Types of acidic dyes
- nigrosin
- eosin
- acid fuchsin
53
Acidic and basic dyes are used for what three types of staining techniques?
- simple stains
- differential stains
- special stains
54
A bacteria cell has what charge, so what dye is used?
(-)
| use basic dyes
55
Simple stains
- aqueous solution of a single basic dye
- stains all the (-) charged cells
- nonspecific
56
Types of differential stains
- gram stain
| - acid fast stain
57
Gram stain
- differentiates between gram + and gram - bacteria
58
What is a key tool for identifying species in clinical laboratory?
Gram stain
59
Acid fast stain
- Carbolfuchsin dye
- only for M. bacterium and Nocardia
- Have mycolic acid in cell wall
60
Types of special stains
- endospore
- flagella
- capsule
61
Simple stain steps
- spread culture
- air dry
- fix using methanol or flame
- stain with methylene blue
- wash with water
- blot
62
Steps of gram stain
- methanol to fix
- crystal violet
- iodine which binds to gram + cells
- wash with ethanol
- safranin counterstain
63
Gram positive staining and iodine
due to thick cell wall the stain cannot get out and remains purprle
64
Gram negative staining and iodine
thin wall allows stain to leave
65
What color are gram + cells after adding safranin?
purple
66
What color are gram - cells after adding safranin?
pink
67
Acid fast stain steps
- carbolfuchsin (primary stain)
- heat
- acid alcohol (decolorizer)
- methylene blue (counter stain)
68
What color are acid fast molecules?
pink
69
What color are non-acid fast molecules?
purple
70
What is used for a capsule stain?
negative staining
71
What are the three shapes of bacteria?
- coccus
- bacillus
- spiral
72
Types of spiral bacteria cells
- vibrio
- spirillum
- spirochete
73
Types of coccus cells
- diplococci
- streptococci (chain)
- tetrad
- sardine
- staphylococci (grapes)
74
Types of bacillus
- single bacillus
- diplobacilli
- stretobacilli
- coccobacillus
75
What makes up the external to cell wall part of the prokaryotic cell
- flagella
- pili
- fimbriae
- glycocalyx
- axial filament
76
What makes up the internal to the cell wall part of the prokaryotic cell?
- cell membrane
