1
Q
Coccus
A
Spheres o
2
Q
Bacillus
A
Rods
3
Q
Curved
A
Vibrio, spirillum, corkscrew, or spirochete
4
Q
Diplococcus
A
Pairs of spherical cells
5
Q
Another word for cell shape
A
Morphology
6
Q
Most bacteria’s morphology (cell shapes)
A
Monomorphic (single shape)
7
Q
Several bacteria morphology are
A
Pleomorphic (many shapes)
8
Q
Chains of circular cells
A
Streptococci
9
Q
Staphylococci
A
Grapelike clusters of circular cells
10
Q
Streptobacilli
A
Chains of rods
11
Q
Curved rod
A
Vibrio
12
Q
Tetrads
A
Groups of four
13
Q
Sarcina
A
A cubical packet 8, 16 or even more cube of cells
14
Q
Diplobacilli
A
Pairs of rods
15
Q
Streptobacilli
A
Chains of rods
16
Q
Palisades
A
Cells of a chain, attached and folded creating a side by side row of cells
17
Q
Appendage that can provide motility
A
Flagella and axial filaments
18
Q
Appendage that can be used for attachment
A
Fimbriae
19
Q
Appendage that can be used as a channel for DNA
A
Pili (singular pilus)
20
Q
Monotrichous flagella
A
One flagellum
21
Q
Lophotrichous flagellum
A
Small bunches or tufts of flagella emerging from the same spot
22
Q
Amphitrichous flagella
A
Flagella on both ends of the cell
23
Q
Peritrichous flagella
A
Dispersed randomly all over the cell
24
Q
Chemotaxis flagella function
A
Detective and move in response to chemical signals, positive- toward a favorable chemical and negative- away from a repellant
25
Phototaxis flagellar function
Movement in response to light, photosynthetic bacteria
26
Flagellum reverse direction, causing the cell to stop and change course. Repellant caused.
Tumble
27
Counterclockwise movement of flagella, swimming in a smooth linear direction toward a stimulus
Run
28
Small bristle like fibers sprouting off the surface of bacteria, this causes disease.
Fimbriae
29
S layer
Thousands of copies of a single protein linked together, they provide protection from environmental conditions and are only produced in hostile environments.
30
Glycocalyx is either a ______ or a ________.
Slime layer, capsule
31
Slime layer
Formed loosely around the cell and protects the cell from loss of water and nutrients.
32
Capsule glycocalyx
More tightly bound to a Cell than a slime layer, denser and thicker than a slime layer.
33
Capsules formed by the glycocalyx
Capsules are often formed by pathogenic or disease, causing bacteria and what they can do is protect the bacteria against phagocytic white blood cells so they inhibit phagocytosis.
34
What inhibits phagocytosis?
Capsules formed by the glycocalyx to protect bacteria from WBC
35
Glycocalyx is also important in the formation of _______.
Biofilms
36
4 functions of Glycocalyx
1 protects the cell from white blood cells so it inhibits phagocytosis
2 protect against dehydration
3 keeps nutrients inside the cell
4 may help adhere the cell to the environment
37
3 basic layers of cell envelope
1 cell wall
2 cytoplasmic membrane
3 outer membrane (some bacteria)
38
What does the cell envelope do?
Act as a single protective unit
39
Functions of the cell wall.
Helps maintain cell shape
Provides strong structural support
Prevents osmotic lysis (diffusion of water across a selectively permeable membrane)
40
Osmosis
Passive movement of water across a selectively permeable membrane from an area of low solute concentration to high solute consentration to balance the gradient while protecting the cell walls from bursting
41
Peptidoglycan
Polymer of disaccharide (glycan chains)
NAG and NAM (sugars and amino acids)
Linked by short peptides
Provides a strong but flexible framework
Target of many antibiotics
42
Gram positive cell wall
Thick peptidoglycan 20-80nm thick
Teichoic acid
Lipoteichoic acid
43
Teichoic acid
Short- helps maintain peptidoglycan layer, helps the cell enlarge during cell division
44
Lipoteichoic acid
Long- like an anchor, it holds the layer of peptidoglycan onto the plasma membrane
45
Gram negative cell wall
Thin layer of peptidoglycan 1-3 nm thick.
More flexible (because of thin)
More sensitive to lysis (easier burst)
46
Porin proteins
Gram negative
Little channels that let certain molecules into the cell and can change shape or block the entrance for certain things
47
Lipoproteins
Anchor the outer membrane to peptidoglycan
48
Lipopolysaccharide
LPS- contains endotoxin that causes fever and may cause death.
49
3 differences between gram positive and gram negative
Gram positive has:
Thick peptidoglycan
Teichoic acids
No outer membrane
Gram negatives have:
Thin peptidoglycan
No Teichoic acids
Outer membrane (contains LPS)
50
The gram stain steps
1 crystal violet
2 grams iodine
3 alcohol
4 safranin
51
Cell envelope in gram negative bacteria
Have an extra barrier that make them impervious to some anti microbial chemicals.
Compared to gram positive are more difficult to inhibit or kill
52
What does the cell (plasma) membrane do?
1 it’s a site for energy reactions
(ATP synthesis for prokaryotes)
2 nutrient processing
3 synthesis
4 regulates transport
53
What is cytoplasm
Inside of cell, gelatinous solution. 70-80% water
54
Plasmids
Nonessential pieces of DNA, smaller than chromosomes, passed on to offspring during replication. Some have protective traits such as drug resistance or the production of toxins an enzymes.
55
Ribosomes
Sites of protein synthesis, made of rRNA
56
The bacterial ribosome is
70S
57
The eukaryotic ribosome is
80S
58
Bacterial endospores are
Dormant bodies that can withstand very hostile conditions ex: ultraviolet light, extreme heat, drying, starvation.
59
The two phase life cycle of endospore forming bacteria
1 vegetative cell
Metabolically active and growing
2 endospore
Inert resting condition
60
Sporulation
Spore formation induced by poor environmental conditions (stress)
61
Vegetative cell into an endospore
Sporulation
62
Endospore into a vegetative cell
Germination
63
Archaea cell walls are
Unusual and chemically distinct cell walls. With no peptidoglycan, many found in extreme environments. Important non pathogens.
Microbiology 260
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