The Microbial Worl Flashcards
1
Q
Microscopic organisms
A
Microorganisms/microbes
2
Q
Microbes lives in and on the human body
A
Microbiology/microbiota
3
Q
Binomial system:
A
Genus+species
4
Q
Nomenclature:
A
Binomial system
5
Q
Genus plural:
A
Genera
6
Q
Species other name
A
Specific epithet
7
Q
Difference between genus and species
A
Genus:capitalized
Species:not capitalized
8
Q
Common thing between genus and species:
A
Italicized+underlined مئل وتحته خط
9
Q
Where do we find staphylococcus?
A
On human skin
10
Q
The clustered staphylococcus arrangement?
A
Coccus indicates that they are shaped like spheres دوائر ببعض
11
Q
Aureus meaning:golden what is the golden?
A
Golden is the colour of the colonies of bacterium
12
Q
Types of microorganisms:
A
1) bacteria
2) archaea(old bacteria)
3) fungi
4) Protozoa
5) algae
6) viruses
13
Q
What is the nature of bacteria’s organisms?
A
Unicellular organisms
14
Q
What is the synonym of prokaryotic?
A
Prenucleus
15
Q
Why bacteria is classified as prenucleus?
A
Because they have no nucleus
16
Q
What is the cell wall of bacteria made of?
A
From peptidoglycan
17
Q
What is the type of division in bacteria?
A
Binary fission
18
Q
How do bacteria move?
A
By flagella الأسواط
19
Q
Shapes of bacteria:
A
1) bacillus
2) coccus
3) spiral
4) star shaped/square
20
Q
Theses shapes are what?
1) rod like
2) spherical/ovoid
3) corkscrew/curved
4) pairs/chains/clusters
A
1) bacillus
2) coccus
3) spiral
4) star shaped/square
21
Q
The most common shape of bacteria?
A
Spiral
22
Q
What is the individual bacteria shape?
A
Star shaped/square
23
Q
Where do we find archea?
A
In extreme environments
24
Q
What is the archea cell walls lack to?
A
They have lack peptidoglycan
25
Archea types:
1) methanogenes
2) extreme halophiles
3) extreme thermphiles
26
How does methanogenes produce methane?
By respiration as a waste product
27
Halophiles means what?
Environments like salts
28
Where do we find halophiles?
In slaty environments like Dead Sea
29
What extreme thermophiles mean?
Archea likes heat
30
Where do we find thermophiles?
In sulfurous water like hot springs الينابيع الحارة
31
What is the singular of fungi?
Fungus
32
Is archea eukaryotic or prokaryotes?
Procaryotic
33
Is fungi eukaryotic or prokaryotic?
Eukaryotic
34
What is the structure of the fungi’s cells?
Unicellular & multicellular
35
Whose bigger bacteria or fungi?
Fungi they have oval microorganisms that are larger than bacteria
36
Fungi types:
Yeasts & molds
37
What is the function of molds?
Molds form mycelia
38
Is mycelia visible?
Yes it is
39
What composes the mycelia?
Hyphae(long filaments)
40
The cell walls of fungi are composed from what?
Chitin
41
What is the singular of Protozoa?
Protozoan
42
Protozoa cell’s structure?
Unicellular
43
Is Protozoa prokaryotic or eukaryotic?
Eukaryotic
44
What is the kingdom of Protozoa?
Protista
45
How do we classify Protozoa?
By locomotion
46
Protozoa types:
1) pseudopods
2) cilia
3) flagella
47
How protozoa lives their life?
Free¶sites
48
What is the photosynthetic Protozoa?
Euglena
49
Protozoa reproduction methods?
Sexually & asexually
50
Algae singular is:
Alga
51
Algae eukaryotes or prokaryotic ?
Eukaryotic
52
Is algae photosynthetic?
Yes
53
Algae reproduction?
Sexual & a sexual
54
The cell wall of algae composed of what?
Cellulose
55
Where do we find algae?
1) aquatic environment (oceans,lakes,rivers)
2) soil
3) in association with plant
56
Viruses are cellular or a cellular?
A cellular
57
What are the nucleus acids in viruses?
DNA & RNA
58
What surrounds the nucleic acids in viruses?
Protein coat
59
Viruses reproduction?
By cellular machinery
60
Where do we find viruses?
Inside the cell in host organism
61
Multicellular animal parasites types?
1) flatworms
| 2) roundworms
62
What are the flatworms characteristics?
Cestodes & trematodes شريطة مسطحة شكل الورقة
63
Roundworms characteristics?
Nematodes
64
Roundworms synonym?
Helminths
65
What is the type of animal parasites that we don’t require it as microorganisms?
Roundworms
66
The first observation of microorganisms?
With Magnifying lenses
67
The second observation of microscopy?
On plants slices
68
The cell theory
All living things are composed of cells
69
Spontaneous generation
Life arise spontaneously from non living
70
What are the maggots?
The larvae of flies
71
Maggots arise spontaneously or not?
No they don’t arise spontaneously from meat
72
Spontaneous generation
Heated nutrient fluids poured into covered flasks were soon crowded with microorganisms
Crowded:انخلطت
73
What happens after boiling for the heated nutrient that crowded with microorganisms?
The microorganisms enter the fluid against needham who showed that heating had destroyed some(vital force) is necessary for the spontaneous generation
74
Why Louis Pasteur drew out the neck of the flask into a long S shape?
To prevent the microorganisms in the air from easily entering the flask=To not allowing some air interchange
75
What happens after prolonged incubation?
The flasks remained free of microorganisms
76
What happens if the swan neck was broken?
The microbes enter the flask and grew
77
Aseptic synonym?
Germ-free
78
What are the basics of aseptic techniques?
Pasteur methods
79
The beginning of microbiologist learn?
Aseptic techniques
80
Wine souring experiment?
Wine produces:sour taste +very little alcohol
81
Acetic acid synonym ?
Vinegar
82
Why the wine was going sour?
Because of a “contaminating microbes that change the alcohol into acetic acid
83
How Pasteur could prevent spoilage??
By heating the wine or bear enough to kill the bacteria
84
Heating the wine or bear enough to kill the bacteria?
Pasteurization
85
What is the common thing between souring of wine and infectious disease?
They might involve infection by a microorganisms
86
Microbes cause disease :
Germ theory of disease
87
How the association between microorganisms & a disease happened ?
By proving that silkworm is caused by fungus
88
What causes silk worm?
Fungus
89
Anthrax is a bacterium:
Bacillus anthracis
90
A set of rules for the assignment of microbe as a cause of disease?
Koch’s postulates
91
حفظ فرضيات Koch’s
4
92
Cowpox disease function?
Gave immunity to smallpox
93
How they inoculated/vaccinated the cowpox patients?
By scratching their arm with cow pox infected needle(ابرة)
94
Vaccination
Disease infected needle scratching the arm by it
95
The protection from disease provided by vaccination
Immunity
96
How vaccines work?
The bacterium lose their ability to make disease after that they still retained their ability to induce (تحفز)immunity
97
How bacteria lose their ability?
Lost their virulence or became avirulent
98
What types of bacteria lose their ability?
Fowl cholera
99
The treatment of disease by chemical substances
Chemotherapy
100
Substances prepared from chemicals in the laboratory
Synthetic drugs
101
The chemical substances that are used in chemotherapy
Synthetic drugs
102
Where do they use synthetic drugs?
In chemotherapy
103
What is the synonym of synthetic drugs?
Antibiotics
104
When do we call synthetic drugs antibiotics?
When they are produced naturally by bacteria & fungi
105
How do we produce synthetic drugs naturally?
By bacteria & fungi
106
An arsenic derivative? مأخوذ من الزرنيخ
Salvarsan
107
Salvarsan function?
Effective against syphilis مرض الزهري
108
A survey of dye derivatives the important group of antibacterial صبغة ما بيكون فيها هاد الgroup
Sulfa drugs
109
Sulfa drugs uncovered what?
The antibacterial group
110
What inhibitated the bacterial growth?
Penicillium chrysogenum
111
Penicillium chrysogenum is a kind of?
Mold
112
The study of bacteria ?
Bacteriology
113
The study of fungi?
Mycology
114
The study of Protozoa & parasitic worms? الفطريات والطحالب
Parasitology
115
the study of immunity?
Immunology
116
The study of viruses?
Virology
117
Virus was so simple & homogeneous it could be crystallised ?
- simple
- homogeneous
- crystallized
Tobacco mosaic
118
What is the function of the microorganisms after they are genetically modified?
It’s going to manufacture large amounts of human’s hormones
119
It’s a technology used to make large quantities of protein
rDNA(recombinant DNA)
120
Recycling vital elements ex:
Nitrogen
121
Soul bacteria uses atmospheric nitrogen
Nitrogen fixation
122
What happens for the fixed nitrogen?
It’s going to be incorporated in the living organisms after that it’s going to return to being gaseous
123
Why the nitrogen fixed returns to be gaseous?
To make up the nitrogen cycle
124
Why there are a decomposition for the organic wastes and dead plants and animals?
To produce CO2 to the etmosphere
125
Cyanobacteria and higher plants use the carbon dioxide for animals during photosynthesis what it is & why?
Algae,to produce carbohydrates for animals /fungi /bacteria
126
Bioremediation
Microbes are used in treatment of sewage & treating oil spills &toxic waste sites
127
What is the function of bacillus thuringiensis
Are used in control of insect nests
128
Recombinant DNA technology function?
1Production of insulin interferon clotting substances
2) vaccines
3) to improve appearance,flavour & shelf life of fruits and vegetables
4) resistance to insects and microbial diseases
5) increased temperature tolerance in crops
129
Replacing missing or detective genes in human cells
Gene therapy
130
Resistance to insects & microbial diseases
Agricultural applications
131
Why the genetically strains of bacteria have been developed?
1) to protect fruit against frost damage
2) to protect modified bacteria
3) to control insects that damage crops
132
Mad cow disease scientific name
Bovine spongiform encephalopathy
133
Emerging infectious disease ex
Mad cow disease
134
What causes mad cow disease?
By prions
135
Infectious protein
Prion
136
E.coliO157:H7infections
Prion
137
Units of measurement
دراستهم من الكتاب
138
Microscopes characteristics
1) magnification
| 2) resolution or resolving power
139
The ability to enlarge objects
Magnification
140
The ability to distinguish between two points on an image
Resolution
141
The total power of magnification of light microscopes is obtained by ?
Multiplying objective lens power by ocular lens power
142
A mathematical constant that describes the relative efficiency of a lens in bending light rays
Numerical aperture
143
Resolution & wavelength
عكسي
144
Prevents refractive loss that normally occurs as peripheral light passes from the slide into the air
Refractive index
145
Treponema pallidum are best seen with?
Dark field microscopy
146
The condenser blocks light from entering the objective directly
Opaque disk
147
What kind of light is seen as image?& why?
Peripheral light,because there is no direct background light the specimen appears light against a black background
148
Dark field microscope function
Examine live microorganisms
149
Why phase contrast microscopy is useful the most?
Because the internal structure of a cell become (more sharply defined permitting detailed examination )of living microorganisms
150
Unstained cell lack contrast & can be difficult to distinguish
Internal components of a live
151
Where the light patterns come from in the phase contrast microscope?how?
- The regions /devices that vary in constrast
| - these devices transform changes in light waves passing through the specimen into differences in light intensity
152
The phase contrast microscope
| function?
Useful in observing intracellular structures
153
Where do we use phase contrast microscope Useful in observing intracellular structures?
- In bacterial spores
| - the locomotor structures of eukaryotic cells
154
In the phase contrast microscope where is the source of light rays?
- Directly from the light source(set1)
| - reflected or diffracted from a particular structure in the specimen(set2)
155
Set1 & 2 together what they form?
An image of the specimen on the ocular lens
156
An image of the specimen on the ocular lens consist from what?
- in phase:areas that are relatively light
| - out of phase: through shades of gray to black
157
Dyes that show fluorescence
- Acridine
| - fluorescein
158
How the dyes show fluorescence?
Illuminated by ultraviolet rays emiting visible light
159
Flurorescent dyes are fixed to what?
To specific anti bodies
160
Where do the fluorescent fixed to specific antibodies?
In diagnostic procedures
161
Fluorescent antibodies function?
1) to detect the causative agent in disease like: Syphilis & chlamydiosis
2) combine with antibodies against specific type of bacteria (the antibodies illuminated with ultraviolet light)
3) in treponema antibody absorption(shows as green cells against a darker background)
162
Electron microscopes use what?
Beam of electrons
163
How do the electromagnetic lenses work?
Use a focus beam of electrons onto a specimen
164
Resolving power of electron microscope is greater than the other microscopes?
True
165
How much the wave length of the electron microscope in general is?
- 100000X(smaller than the wave length of the visible light)
| - 10000-100000
166
Types of electron microscopy?
1) TEM(transmission electron microscopy)
| 2) SEM(scanning electron microscopy)
167
(1)Beams of electrons from an electron gun passes through ultrathin section of the specimen?
TEM
168
How TEM’s electrons passes from the electron gun?what happens next?
- Through ultrathin section of the specimen
| - electrons pass through the specimen and are scattered تشتتت
169
(2)The specimen characteristics in TEM?
Placed on a copper mesh grid (not on glass)
170
Where do the magnetic lenses focus the image?
Onto a fluorescent screen
171
How does the TEM appears like what?
As many light & dark areas
172
How the TEM appears?
Depending on the number of electrons absorbed by different areas of the specimen
173
TEM magnification?
10000-10000000X
174
SEM’s function?
1) Overcome the sectioning problems associated with a TEM
| 2) provides striking 3D views of specimens
175
SEM steps?
1) electron gun produces primary electron beam
| 2) these electrons pass through electromagnetic lenses & directed over the specimen
176
The difference between primary & secondary electrons?
The primary electron beam knocks electrons out of the surface of the specimen & secondary electrons produced are transmitted to an electron collector amplified and used to produce an image on a viewing screen that is saved as a scanning electron micrograph
177
SEM
- 1000 to 500000X
| - 10nm
178
Thin film of material containing the microorganisms spread over the surface of the slide and allowed to dry
Smear
179
After smearing the slide it’s going to be fixed by passing it through the flame of a Bunsen burner several times
Heat fixation
180
Smear side up or by covering the slide with methanol for 1 minute
Chemical fixation
181
Before the microorganisms can be stained they must be fixed attached to the microorganisms and fixes them to the slide
Fixing simultaneously
182
Fixing simultaneously functions:
1) kills the microorganisms
2) fixes them to the slide
3) preserves various parts of microbes in their natural state with only minimal distortion
183
Stains synonym
Chromophore
184
Cations & anions
- basic dyes:cation
| - acidic dye:anion
185
Salts are composed of positive or negative ion coloured substance
Stains/chromophore
186
When bacteria is negatively charged?
Ph=7
187
Basic dyes
1) Crystal violet
2) methylene blue
3) malachite green
4) safranin
188
Whose the dye that dye the back ground,negatively charged bacterial surface?
Acidic dyes
189
Preparing colourless bacteria against a coloured back ground?
Negative staining
190
Negative staining functions?
To observe cell shapes sizes capsules
191
How the negative staining makes their functions?
Because the cells are made highly visible against a contrasting dark back ground
192
Why the negative staining distortions of cell size and shape are minimized?
Because fixing isn’t necessary and the cells don’t pick up the stain
193
What are the acidic dyes?
Eosin , acid fuchsin,Indian ink,nigrosin
194
Positive staining methods are classified:
Simple
Differential
Special
195
The difference between simple & differential stains?
- simple: single dyes
| - differential:two different dyes
196
What are the two different dyes of differential stains?
Primary dye & counterstain
197
Used to study bacterial characteristics as size shape and arrangement?
Simple stains
198
Is added to the solution to intensify the stain to increase the affinity of a stain for biological specimen
Amordant
199
Simple stains dyes:
- methylene blue
- carbolfuchsin
- crystal violet
- Safranin
200
The most useful differential stain is:
Gram stain
201
Gram stain divides bacteria into:
Gram positive:purple
| Gram negative:pink/red
202
Gram positive with the following:
Crystal violet:purple
Mordant (IKI):purple
Decolorisation (ethanol):purple
Counterstain):purple
203
Crystal violet:purple
Mordant (IKI):purple
Decolorisation (ethanol):purple
Counterstain):purple
Crystal violet:purple
Mordant (IKI):purple
Decolorisation (ethanol):purple
Counterstain (safranin)purple
204
Gram negative with the following:
Crystal violet:purple
Mordant (IKI):purple
Decolorisation (ethanol):colourless
Counterstain(safranin):red
205
How the dark violet/purple colour result?
The purple dye +iodine combine in the cell wall in the bacterium
206
The bacteria that retain this colour after alcohol/alcohol and acetone what it is and what happens?
Are gram positive
| Attempt to decolorize
207
The bacteria that lost the colour dark violet/purple after decolorization?
Gram negative bacteria
208
Why the gram negative bacteria lose the colour of dark violet/purple?
Because they are colourless after the alcohol wash they are no longer visible
209
Why the basic dye safranin is applied?
Because they are colourless after the alcohol wash they are no longer visible & it turns the gram negative bacteria pink
210
Safranin has contrasting colour to the primary stain?
Counterstains
211
Why the gram positive bacteria retain the original purple stain ?
Because they are not affected by the safranin counterstain
212
Gram positive bacteria or gram negative bacteria’s cell wall (peptidoglycan)is thicker?
Gram positive bacteria
213
Which bacteria contain a layer of lipopolysaccharide?
Gram negative
214
When applying gram negative & positive what happens to the cells?
Crystal violet & iodine enter the cell walls
215
Crystal violet & iodine alone and in water?
Alone:water soluble
| In water:in soluble
216
What happens when Crystal violet and iodine are in water?
It won’t easily leave the cell wall
217
What happens after adding the gram positive cells to CV-I?
| CV-I :Crystal violet iodine
Retain the colour of the Crystal violet dye
218
What happens after adding the gram negative for the CV-I?
The alcohol wash disrupts the outer lipopolysaccharide layer & the CV-I is washed out of the thin layer of peptidoglycan
219
Until what the gram negative & positive are colourless?
- negative: Until counterstained with safranin which they are pink/red dye & they don’t retain the dye
- positive :retain the dye and remain purple
220
Acid fast stain function?
Is used to distinguish certain bacteria that contain waxy materials in their cell walls
221
What kind of waxy materials are in the cell wall?
Mycolic acid
222
What component makes the cell wall resistant to most stains?
Mycolic acid
223
What will penetrate the cell wall staining a red colour to cells that is not removed when the decolorizing agent alcohol is added?
Heating the carbolfuchsin(acid fast)
224
Why the majority of bacteria lose the red colour when acid alcohol is added?
Because they don’t have mycolic acid in their cell wall
225
The kind of bacteria that don’t have mycolic acid in their cell wall what happens to them?
They then take up the counterstain methylene blue & refer to non acid fast
226
How do we distinguish the pathogenic bacteria?
By :
- Mycobacterium tuberculosis
- Mycobacterium leprae
227
Actinomycete genus nocardia & nocardia asteroides are:
Acid fast
228
To colour parts of microorganisms stains?
Special stain
229
Special stains ex
Endospores
Flagella
Capsules
230
What is the process that produce endospores?
Sporogenesis
231
When the sporogenesis is released?
Upon the death of the cell
232
What produces the endospores?
Vegetative cell
233
Endospores structure
Resistant/dormant
234
Endospores function ?
Protects a bacterium from adverse environmental conditions
235
Why is free spore a dormant structure highly resistant nature?
Because 1)the spore acts like a sieve that excludes large toxic molecules like lysozyme
2)it contain of keratin and other core specific proteins which makes the endospore extremely hardy
236
Why endospores can’t be stained by ordinary methods like simple staining and gram staining?
Because the dyes don’t penetrate the endospores wall
237
The most commonly used endospores stain is :
Schaeffer Fulton endospore stain
238
The detection of endospores function?
Useful in the identification of some bacteria including species of bacillus & clostridium
239
Bacillus anthracis causes
Anthrax
240
Clostridium botulinum causes:
Botulism
241
Clostridium tetani causes:
Tetanus
242
Clostridium perfringens causes:
Causes gas gangrene
243
Primary stain heats fixed smear?
Malachite green
244
The heat from malachite green function?
Helps the stain penetrate the endospore wall
245
Why the preparation is washed for 30 seconds with water?
To remove the Malachi green from all of the cells parts except the endospores
246
Why the safranin counterstain is applied to the smear ?
To stain portions of the cell other than endospores
247
What happens after the safranin counterstain is applied to the smear ?
The endospores appears green with red or pink cells
248
Is a method of observing the microbial capsule an extra cellular layer surrounding the cell that is composed of polysaccharides and polypeptides
Capsule staining or negative staining
249
Determining the organisms virulence
Capsules
250
The degree to which a pathogen can cause disease
Virulence
251
Capsule characteristics
Resistant to staining/water soluble may be dislodged or removed during rigorous washing
252
How the capsule can be revealed?
It can be revealed by using a negative stain combination of acidic and basic stains
253
The difference between acidic & basic stain?
Acidic stain:India ink or nigrosin /colours the background
| Basic stain:safranin colours the cell
254
How the capsule appears ?
Clear halo around the cell
255
What causes bacteria pneumonia?
Klebsiella pneumoniae/streptococcus pneumoniae
256
What kinds of bacteria form capsules?
Klebsiella pneumoniae/streptococcus pneumoniae
257
A method of revealing flagella the tiny slender filaments used by bacteria for locomotion
Flagellar staining
258
Flagella arrangements?
Monotrichous
amphitrichous
Lophotrichous
Periodic houses
259
Where do we use the flagella arrangements?
In bacterial identification
260
Procedure uses a mordant and the stain carbolfuchsin to build up the diameter ms of the flagella until they become visible under the light microscope
Flagellar staining
261
Prokaryotic synonym?
Prenucleus
262
Genetic material?
DNA
263
DNA characteristics in prokaryotic?
- one cellular chromosome
| - not enclosed within a membrane
264
Is DNA in prokaryotic cells enclosed within a member?
No
265
Which bacteria has 2 chromosomes?
Vibrio cholerae
266
Is their any prokaryotic bacteria has a linearly arranged chromosome?
Yes
267
Membrane enclosed organelles in procaryotic?
Lacking of membrane enclosed organelles it has a few membrane enclosed organelles
268
Which membrane enclosed organelles in prokaryotic?
Inclusions
269
DNA association with histones?
Is not associated with it
270
Cells wall in prokaryotic cells?
Contain peptidoglycan
271
Prokaryotic cells division?
Binary fission
272
Nucleus in eukaryotic?
Bounded by a membrane
273
DNA in eukaryotic?
Is found in multiple chromosomes
274
DNA association in eukaryotic?
With proteins: histones and non histones
275
Eukaryotic cells division?
Mitotic apparatus
276
Membrane enclosed organelles in eukaryotic?
Posses ✅
277
Membrane enclosed organelles in eukaryotic like what?
- Mitochondria
| - endoplasmic reticulum -chloroplasts
278
Bacteria range in size?
0.2-2Mm
279
Bacteria range in length ?
2-8Mm
280
Basic bacterial shapes:
- Coccus
- bascillus
- spiral
281
Coccus synonym?
Spherical
282
Coccus plural?
Cocci
283
Cocci shapes?
- oval
- elongated
- Flattened on one side
284
Bacillus plural?
Bacilli
285
Bacillus synonym?
Rod shaped
286
Arrangement of spherical cocci bacteria?
- single cocci
- diplococci
- streptococci
- tetrads
- sarcinae
- staphylococci
287
Which type of bacterial cells form pairs?
Diplococci
288
Which type of bacterial cells form chains?
Streptococci
289
Which type of bacterial cells form groups of four?
Tetrads
290
Which type of bacterial cells form groups of eight (cube like)?
Sarcinae
291
Which type of bacterial cells form (grape like clusters)?
Staphylococci
292
Bacilli shapes?
- Single bacilli
- diplobacilli
- streptobacilli
293
Which type of bacilli appear in pairs &chains?
- diplobacilli
| - streptobacilli
294
Bacilli are oval & look so much like cocci?
Coccobacilli
295
Bacilli shapes:
Straws
Tapered ends:cigars
Oval:coccibacilli
296
Bacterial shape/captilized& italicized?
Bacillus & specific genus bacillus
297
Spiral bacteria shape?
Come or more twists/never straight
298
Bacteria that look like curved rods?
Vibrios
299
Spirilla singular?
Spirillum
300
Spirilla characteristics?
- helical shape like a corkscrew
- fairly rigid bodies
- are motile by means of flagella
301
Spirals are helical & flexible:
Spirilla & spirochetes
302
Spirochetes characteristics?
- helical shape
- flexible
- have axial filaments for motility
303
Single pleomorphic ?
Monomorphic
304
Prokaryotic cell wall structure?
Glycocalyx/flagella/axial filaments/fimbriae/pili
305
Glycocalyx in prokaryotic cell wall?
Polysaccharide & polypeptide
306
Glycocalyx:
- organized & tightly attached to the cell wall
- unorganized & loosely attached to the cell wall
- Capsule
| - slime layer
307
Capsules function?
1) contribute in bacterial virulence
| 2) protect pathogenic bacteria from phagocytosis by the cells of the host
308
Glycocalyx function?
Helps bacterial cells in a biofilm attach to the surfaces
309
Streptococcus mutans work mechanism?
Is an important cause of dental caries attaches itself to the surface of teeth by glycocalyx
310
Encapsulated bacteria:
- streptococcus pneumoniae
- haemophillus influenzae
- bacillus anthracis
311
A cause of pneumonia?
Streptococcus pneumoniae
312
An infection of the lung?
Streptococcus pneumoniae
313
Cause of meningitis?
Haemophilus influenzae
314
The cause of anthrax?
Bacillus anthracis
315
Flagellar filaments?
Are composed of flagellin protein protein
316
The long outer most region?
Filament
317
The filament in flagella is attached to what?
To hook (wider hook)
318
Flagella parts?
- Flagellar filaments
- filament
- hook
- basal body
319
Basal body anchored to what?
- in gram negative : anchored to cell wall & plasma membrane
- in gram positive: anchored to plasma membrane
320
Flagella types:(arrangement)
- monotrichous
- lophotrichous
- amphitrichous
- peritrichous
- atrichous
321
Single flagellum at one pole?
Monotrichous
322
A truft of flagella coming from one pole or both?
Lophotrichous
323
One flagellum at each pole?
Amphitrichous
324
Flagella distributed over the cell?
Peritrichous
325
Lack flagella?
Atrichous
326
Bacteria movement?
Running & tumbling
327
Flagella movement?
Clockwise/counter wise:
- run/swim(directional movement)
- tubmbles(random changes in direction)
328
Bacteria movement toward or away is
Taxis
329
Stimuli?
- include chemicals:chemical stimuli
| - include light:phototaxis
330
Receptors locations in motile bacteria?
In/under the cell wall
331
Receptors function in motile bacteria?
Pick up chemical stimuli such as: oxygen/ribose/galactose
332
Flagellar protein?
H antigene
333
H antigene function?
Is useful for distinguishing among serovars or variations within a species of gram negative bacteria
334
H antigene Ecoli association with what?
With food borne epidemics
335
Spirochetes movement?
Move by means of axial filaments or endoflagella
336
Bundles of fibrils that arise near cell poles beneath an outer sheath and wrap in spiral fashion around the cell?
Endoflagella
337
Gram negative bacterial cells have numerous hair like appendages?
Fimbriae & pili
338
Fimbriae singular ?
Fimbria
339
Pili singular?
Pilus
340
shorter than flagella
have pilin protein
G-ve
Hair like appandages
Pili
341
Fimbriae?
Occur at the poles of the bacterial cell/can be evently distributed over the entire surface of the cell
342
Fimbriae in bacteria?
From a few to several hundred per cell
343
Fimbriae function?
Help bacteria adhere to epithelial surfaces
344
Fimbriae on the bacterium Neisseria gonorrhoea function?
1) The causative agent of gonorrhoea
| 2) help the microbe colonize mucous membranes
345
Fimbriae of E. coli 0157 function?
Enable the bacteium to adhere to the lining of the small intestine where it causes watery diarrhea
346
Pili length & number?
Longer than fimbriae & one or two per cell
347
Pili are involved in motility & transfer of DNA from one cell to another in a process called
Conjugation
348
Pili for conjugation?
Sex pili
349
The bacterial cell wall structure?
Semirigid
350
The bacterial cell wall structure function?
1) giving the characteristic shape of the cell
2) prevent bacterial cells from rupturing
3) serves as point of anchoring for flagella
351
Gram positive cell wall:
1) many peptidoglycan layers
2) teichoic acid
3) flagella basal body (plasma membrane)
352
Gram negative cell wall
1) linear peptidoglycan
2) outer membrane
3) flagella basal body in cell wall plasma membrane
353
The chemical composition of the cell wall function?
Is used to differentiate major types of bacteria
354
Cell wall importance & function?why?
Because it contributes to the ability of some species to cause disease & is the site of action of some antibiotics
355
Macromolecular network in cell wall
Peptidoglycan:
- murein
- mucopeptide
356
Disaccharide portion is made up of monosaccharides?
Peptidoglycan:
N-acetylglucosammine (NAG)
N-acetylmuramic acid (NAM)
357
NAM & NAG linked in what?
-Rows/10-65 sugars
| -
358
NAM & NAG form what?
Carbohydrate backbone(the fly can portion of peptidoglycan)
359
Adjacent rows are linked by what?
By polypeptides(the peptide portion of peptidoglycan?
360
Tetrapeptide side chains consist of what?
Four amino acids attached to NAM in the backbone
361
The amino acids in tetra peptide occurring location?
In pattern of L & D forms
362
Parallel tetrapeptide side chains structure?
1) directly bonded to each other
| 2) linked by a peptide cross bridge(consisting of a short chain of amino acid)
363
Periplasmic space location in gram positive?
Between cell wall and plasma membrane
364
Periasmic membrane in gram positive composed of what?
Lipoteichoic acid
365
Teichoic acid in gram positive consist of what ?
Alcohol/glycerol/ribitol/phosphate
366
Teichoic acids classes:
- lipoteichoic acid
| - wall teichoic acid
367
Lipoteichoic acid in gram positive?
Spans peptidoglycan layer & linked to the plasma membrane
368
Wall teichoic acid?
Linked to the peptidoglycan layer
369
Teichoic acid function?
1) bind Andre regulate the movement of cations
2) protect bacteria from cell lysis
3) provide mouth of walls antigenic specificity
4) make it possible to identify gram positive bacteria by certain laboratory tests
370
Gram negative cell walls ?
Thin layer of peptidoglycan & an outer membrane
371
More susceptible to mechanical breakage?
Gram negative cell wall
372
The region between the outer membrane and the plasma membrane
Gram negative bacteria periplasmic space
373
Peptidoglycan in gram negative bacteria?
Is bonded to lipoproteins in the outer membrane & is in the peri plasma a gel like fluid in the periplasmic space
374
Periplasm in g-be in cell walls?
1) contains high concentration of degradative enzymes
| 2) transport proteins
375
Does g-ve have teichoic acid?
No
376
The outer membrane of gram negative consist of:
1) lipopolysaccharides
2) lipoproteins
3) phospholipids
377
Outer membrane functions:
1) evading phagocytosis because it’s negatively charged
2) the actions of compliment
3) provides a barrier to (detergents /heavy metals/bile salts/certain dyes/antibiotics) & digestive system enzymes (lysozyme)
4) permeability of the outer membrane is due to porins
5) components of lipopolysaccharide(lipid A/a core polysaccharide/O poly saccharide)
378
Lipid A function as an endotoxin:
1)responsiple for the symptoms associated with infections by gram negative bacteria such as:
A)fever dilation of blood vessels & shock & blood clotting
2)core poly saccharide is attached to lipid A & the O polysaccharide extends outward from the core polysaccharide
379
O polysaccharide function as an antigen?
Is useful for distinguishing serovars of gram negative bacteria
380
Why we call lipid A endotoxins?
Because they are integral part of the cell wall in contrast to exotoxins which are freely released from the bacteria
381
Mycoplasma characteristics:
- smallest known bacteria
- grow & reproduce outside living host cells
- don’t have cell walls
- have sterols in their plasma membrane
382
Archea & walls
Lack of walls composed of polysaccharides+ proteins but not peptidoglycan
383
Similar substance to peptidoglyacn in arches cell walls?
Pseudomurein
384
Pseudomurein contains what instead of NAM?
- N-acetyltalosminuronic acid
| - Lack of D-amino acids found in bacterial cell walls
385
Why arches is gram negative?
Because they don’t contain peptidoglycan
386
How much the acid fast cell wall of mycobacterium & nocardia contains mycloic acids?
60%
387
The mycloic acid & peptidoglycan are held together by what?
By polysaccharides
388
Why the mycolic acid & peptidoglycan are held together by polysaccharides?
Because of its unique cell wall when it’s stained by the acid fast procedure it will resist declorization with acid alcohol & stain red & the colour of the intial stain carbolfuchsin
389
Acid fast procedure:
it will resist declorization with acid alcohol & stain red & the colour of the intial stain carbolfuchsin
390
The colour of methylene blue counter stain?
All other bacteria (except mycobacterium & no cardia) will be declorized and stain blue
391
What happens if the mycolic acid layer is removed from the cell wall of acid fast bacteria?
They will stain gram positive with gram stain
392
Why chemicals that damage bacterial cell walls or interfere with their synthesis don’t harm the cells of an animal host?
Because the bacterial cell wall is made of chemicals unlike those in eukaryotic cells
393
Is a good target for antibacterial drugs?
The peptidoglycan cell wall
394
Penicillin a/cephalosporins/vancomycin drugs function?
inhibit the synthesis of peptidoglycan by inhibiting the transpeptidase that makes the cross links between the two adjacent tetrapeptide side
395
Lysosome enzyme location?
Is present in human tears /mucus/saliva
396
Lysozyme function?
Can cleave the peptidoglycan backbone by breaking its glycosyl bonds(thereby contributing to the natural resistance of the host to microbial infection)
397
Gram positive bacteria that has lost its cell wall and is surrounded only by the plasma membrane (complete removal of gram positive cell wall)
Protoplast
398
Gram negative cell treated with lysozyme retain much of the outer membrane layer (incomplete removal of gram negative cell wall)
Spheroplast
399
Are sensitive to rupture by osmotic lysis?
Protoplast & spheroplast
400
L-forms:
Gram positive & negative
Don’t make a cell wall
L forms arise spontaneously from a mutation in the cell wall forming genes
-they can be induced artificially by treatment with chemical such as lysozyme or penicillin that disrupts the cell wall
-L forms can live and divide repeatedly or return to the walled state
