Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Fundamental Of Disease > bacteria Structure > Flashcards

bacteria Structure Flashcards

(86 cards)

Start Studying
1
Q

What are glycocalyces?

A

Gelatinous, sticky substances surrounding the outside of the cell.

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

What does glycocalyces contain?

A

Polysaccharides , polypeptides, or both

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

Where are two types of glycocalyces. What are they?

A

Capsule and slime layer

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

Describe the structure of a capsule of the bacteria?

A

Composed of organized repeating units of organic chemicals. And is firmly attached to the surface of the cell.

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

What is the purpose of the capsule?

A

Protects cells from drying out and may prevent bacteria from being recognized and destroyed by host

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

What is a slime layer of a bacteria?

A

A sticky layer that allows prokaryotes to attach to surface. It is loosely attached to the cell surface. It is water souble and protects cells from drying out.

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

Examples of bacteria that has a slime layer

A

Pseudomas, streptococcus mutans uses is a gensus that adheres To the teeth of humans and can cause tooth decay because it uses sucrose to synthesis a biofilm teeth.

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

What is a flagellum?

A

The flagellum is a long protein structure responsible motility .

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

How does a flagellum work?

A

By spinning like a propel, using proton motive force as energy, the flagella pushes like a ship .

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bacteria with a flagellum can cause disease . Name one?

A

Helicobacter pylori is a bacterium that causes disease. It has a powerful flagellum at one end of it spiral shaped cell, it allows H.pylori to penetrate the vicious mucous gel that coats the stomach.

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

The flagellum is composed of three parts. What are they?

A

Filament, hook, basal body

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

Describe the filament structure of the flagellum?

A

Is made up of a protein called flagellin. The flagellin is arranged in a helical structure with a hollow core.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the hook portion of the flagellum.

A

Connects the filament to the cell surface and is curved.

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

Describe the basal body of the flagellum

A

Basal body anchors the flagellum to the cell wall and the cytoplasmic membrane

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

What does monotrichous mean?

A

Having a single flagellum at only one pole or end. E.g. Vibrio sp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does peritrichous mean?

A

Having cilia or appendicular organs around a bacterium e.g ecoli

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

What does lophotrichous means?

A

Having two or more flagella at one end. E.g. Pseudomonas sp

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

What does amphitrichous mean?

A

Having a flagellum at both ends e.g spirilum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the purpose of bacterial flagella structure?

A

Movement

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

What protein makes up bacterial flagella structure?

A

Flagellin, deposited in a helix at the lengthening tip

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Facts about the bacterial flagella structure?

A

Base of filament inserts into hook

Filaments capsule of rotating 360 degree

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What anchors filament ?

A

Basal body anchors filament and hook to cell wall by a rod and a series of either two or four rings of integral proteins.

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

Sex pilus

A

Used for the transfer of DNA , longest pilus , it is used to join the two cells for e.g ecoli.

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

What are pilus ?

A

Hair like projections of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are endospores?
Dormant cell, Produced when starved, Resistant to adverse conditions such as temp,organic solvent.
26
What is the chemical that is in endospores?
Calcium dipicolinate
27
Example of bacteria with endospores
Bacillus and clostridium
28
What is the structure of endospores?
Peptidoglycan layer, cortex, between two membranes, less cross linked, dehydrated muramic acid (lactam)
29
Definition of cell wall
Consist of cell membrane, cell wall included embedded proteins and glycocalyces or capsule.
30
Functions of the cell wall
``` Barrier ( osmotic protection, regulated environment (ph, solute gradients) Solute transport Electron transport Electrochemical gradients/ ATP synthesis Motility Lipid biosynthesis Protein secretion ```
31
What is attached to the phosphates on the cytoplasmic membrane structure
Calcium ions and magnesium ions
32
Function of Permeability barrier
Prevents leakage and functions as a gateway for transport of nutrients into and out of the cell.
33
What is the function of protein anchor?
Site of many proteins involved in transport, bioenergetics and chemo taxis
34
What is energy conservation?
Site of generation and use of the proton motive force.
35
What is the difference between gram positive and gram negative bacteria?
Gram positive bacteria have a thick layer of peptoglycans
36
Gram positive bacteria have a thick or thin peptidoglycan layer
Thick
37
Why are teichoic and lipoteichnoic acids important?
Serotyling
38
Facts of teichoic acid
``` Found in gram positive bacteria Impact a negative charge on bacteria Binds Mg2+ May be bound to membrane lipids Contain ester linkages to other sugars and D- alanine Involved in adherence to host tissue. ```
39
Teichoic acids contain
Acidic polysaccharides containing glycerol phosphate or ribitol phosphate
40
Peptidoglycan layer is known as
Murein
41
Importance of peptidoglycan layer
Critical for resistance to osmotic pressure Hydrophilic nature provide resistance to some hydrophobic compounds. Very important target for antibiotics
42
What is the chemical structure of peptidoglycan ?
N- acetylmuranic Diaminopimelic acid Repeating structure
43
A lipopolysachharide molecule that is released from the outer membrane of gram negative bacteria cell walls and causes the symptoms of the bacterial infection is called
Endotoxin
44
The chromosome in prokaryotes are located within
Nucleoid
45
Name a bacteria that lacks a cell wall
Mycoplasma
46
What shape does vibrio app have
Curved rod
47
What shape does corynebacterium have?
Club shaped
48
What shape does clostridium have
Spore forming rod
49
Functions of cell wall
Osmotic protection, solute transport, electron transport, electrochemical gradient/ ATP synthesis, motility.
50
Bacteria have which ions in their cytoplasmic membrane ?
Mg and ca2t
51
Core polysaccharide for endotoxins
Glu, gal. Hep,,KDO,GLUCOSAMINE
52
Gram negative envelope.
Outer membrane has pores formed by porin proteins large enou to diffuse trisaccharides.. Outer membrane can exclude large compounds .e.g vancomycin
53
LPS outer membrane
Oligosaccharide O side chain, core provides resistance to hydrophobic compounds. (Base for enteric bacteria)
54
DAP linkage is mostly seen in which category of bacteria ?
Negative
55
Peptidoglycan layer is porous or non porous?
Porous
56
Perisplasmic space
The space between the cytoplasmic membrane and the outer membrane. It contains numerous proteins Contains a peptidoglycan layer Virulence factor such as hyaluronidase, b lactamse
57
Grain stain order
Crystal violet,gam iodine,decoloriser, safinin red
58
Mycobacterial cell envelopes
``` Lipid rich cell wall Acid fast Slow growth Resistance to penicillin and vancomycin Clumping q ```
59
Two bacteria that lack cell wall are
Mycoplasma and chlamydiacea such as chlamydia, chlamydophilia,
60
Mycoplasmas
Single membrane contains sterols, which are important for ridity Related to gram positive bacteria Smallest free livi f bacteria
61
Chlamydiaceae
Two membranes Some genes for peptidoglycan synthesis found in genome Obligate intracellular parasites Non replication intracellular body,
62
Initial phase
Cells enlarge , metabolic activity increases
63
Exponential phase
Rapid multiplication, bacteria are susceptible to antibiotics
64
Stationary phase
Slow multiplication, some cells die,synthesis of Dana continues to some level, smaller cells appear
65
Decline
Decrease of the umber of viable cells due to lack of nutrients decrease in ph, accumulation of toxins
66
Growth of microbial populations
Binary fision( 30 minutes),DNA replicates, cell elongates then divides (60 minutes) , population doubles with each generation(90min),exponential growth ( 120 minutes)
67
Obligate aero best
Only aerobic conditions, presence of catalase and superoxide dismutase allows toxics form of oxygen. To be neutralised
68
Facultative anaerobes
Both aerobic and anaerobic growth, growth is excellent when oxygen is present
69
Obligate anaerobes
Only anaerobic growth, ceases in presence of oxygen, lack enzymes that allow tolerance to oxygen
70
Microaerophiles
Only aerobic growth,oxygen required in low concentrations
71
Hyperthermophiles
70- 105
72
Mesophiles
15- 45
73
Psychophiles
-5 - 15
74
Bacterial genome is composed of one circular chromosome
4-5 MB long Contains double stranded molecules of DNA arranged in circular form Condenses by supercoiling and looping into a dense,y packed nucleiod body,
75
Plasmids
Plasmids are circular DNA molecules present I. The cytoplasm of bacteria Capable of autonomous replication Can transfer genes to each other Present in yeast
76
Transformation
Transfer of genetic information through the activity of DNA .
77
Experiment for transformation
Griffith expirement with mice
78
Bacterial transformation
DNA binds to the surface of a component cell and is cleved into fragment of about 15 mb
79
Natural transformation
Recipient cell has enzymatic machinery for DNA import
80
Artificial transformation
Damage to recipient cell walls allow donor DNA to enter cells.m
81
Electroporation
Mix donor DNA with recipient bacteria an subject to very brief high voltage
82
Lipofection
Used to transform cells of animals yeast plants and bacteria
83
Bacterial conjugation
Is genetic recombination in which their is a transfer of dnafrom a living organism to a recipient bacterium . Often using a sex pilus
84
3 conjugation process
Ft conjugation HFr conjugation Resistance plasmid conjugation
85
Two types if transduction types
Lyric and lysogenic
86
Transposon
Are transposable. Genetic elements that carry one or more other genes in addition to those which are essential for transposition

Fundamental Of Disease (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions