Microbiology Flashcards
1
Q
What is Mutualism?
A
Both the host and microbe benefit
2
Q
What is Commensualism?
A
- microbe benefits
- host is unharmed
3
Q
What is Parasitism?
A
Invading organism benefits from host at the expense of the host
4
Q
What is Symbiosis?
A
- living together
- with the environment
- no judgment
5
Q
What is Pathogenicity?
A
the interaction between an organism and host
6
Q
How do cells with an anabolic metabolism get and use proteins?
A
- DNA can make needed proteins
- ingested proteins are broken down into amino acids and the cell rearrange them into the proteins that are needed
7
Q
How do cells with an anabolic metabolism get energy?
A
- biosynthesis
- break down glucose so that the cell can use its byproducts to make new sugars that the cell needs
8
Q
What is a pathogen?
A
An organism or agent capable of causing disease
9
Q
What is a disease?
A
And illness that alters body structures and functions
10
Q
What are symptoms?
A
Subjective changes in body function
May not be observable or measurable
Pain, malaise
11
Q
What are signs?
A
Objective changes, observable, measurable
12
Q
What is a syndrome?
A
Specific group of symptoms and signs that always accompany a particular disease
13
Q
What is a communicable disease?
A
A disease easily spread from one host to another, either directly or indirectly
14
Q
Example(s)of a communicable disease
A
Chickenpox
Measles
Genital herpes
Tuberculosis
15
Q
What is a contagious disease?
A
A disease easily spread directly from one host to another
16
Q
Examples of contagious diseases
A
Chickenpox
Measles
17
Q
What are non-communicable diseases?
A
Diseases not spread from one host to another
18
Q
How are non-communicable diseases caused?
A
Microbes that normally inhabit the body and only occasionally produce disease
microbes that reside outside the body and produces disease only when introduced into the body
19
Q
Example of a non-communicable disease
A
Tetanus
20
Q
What is a sporadic incidence?
A
Occurs only occasionally
Typhoid fever
21
Q
What is an endemic incidence?
A
Constantly present in a population
Native to a population
Colds
22
Q
What is an epidemic incidence?
A
Many hosts in a given area acquire a certain disease in a relatively short period of time
23
Q
Examples of diseases that cause epidemic incidences
A
Influenza, aids, gonorrhea
24
Q
What is a pandemic incidence?
A
An epidemic disease that occurs in multiple parts of the world
Disease that affects the majority of the population of a large region
25
Example of a pandemic disease
Dental caries, Periodontal disease
26
What is virulence?
Degree of pathogenicity
How bad is it?
27
What is a vector?
Intermediary hosts that carry the disease from one species to another
28
What is a fomite?
Vehicle
Inanimate objects that transmit disease
29
What is a biological vector?
Bites, saliva
30
What is a mechanical vector?
Spreading it through biological organisms such as arthropods
31
What is a reservoir?
A site where infectious agents survive
Environment, body
32
How do pathogens enter the body?
Pathogen must overcome physical barriers such as skin or mucous membranes
Enter via wounds, ulcers, animal and insect bites
33
What happens once a pathogen enters the host?
Multiply, spread, cause disease
Colonize areas they are suited to
34
What is an acute disease?
One that develops more rapidly but lasts only a short time
35
What is a chronic disease?
Develops more slowly, body reactions may be less severe, but disease is continued or recumbent for long periods
36
Examples of chronic diseases
Infectious mononucleosis
FeLV
Tuberculosis
Hepatitis B
37
What is zoonosis or a zoonotic disease?
Disease that can be transmitted between animals and humans
38
How were zoonotic diseases recognized?
Similarity in physical abnormalities between animal and human diseases
Identification of causative agents due to invention of the microscope
39
What are the classics zoonoses?
Plague
Rabies
Tuberculosis
40
What are the new zoonoses?
Lyme disease
Hantavirus pulmonary syndrome
West Nile virus
41
When was Lyme disease discovered?
1970s
42
When was the hantavirus pulmonary syndrome discovered?
1993
43
When was West Nile virus discovered?
1999
44
What are emerging zoonoses?
Zoonotic diseases caused by new agents or previously known agents appearing in places or in species where it was previously unknown
45
Example of an emerging zoonoses
Closely related virus strains may mutate
Influenza
46
When did zoonotic diseases start?
When animals were domesticated in 6000 BC
47
What are the environmental conditions that allow zoonotic diseases to transmit?
Overcrowding of animals and humans
Barnyard conditions
Poor sanitation and personal hygiene
48
How do insects and rodents contribute to disease transmission?
Insects and rodents allow transmission of disease from animals do humans under certain conditions
They are carriers of disease
49
How are zoonotic diseases spread worldwide?
Trade routes
50
How does international travel contribute to zoonotic transmission?
Allows people, goods, food, rodents, and insects to move easily between populations
51
What were the early prevention and control measures for zoonotic diseases?
Boiling milk
Religious laws prohibiting the eating of pork
Culling animals showing signs of disease
Quarantining ships at ports
52
Who are the people most at risk of zoonotic diseases?
- Farmers
- Slaughterhouse workers
- Laboratory workers
- Human health and veterinary care personnel
- people frequenting wildlife habitats
– People in contact with pets or exotic animals
53
What are the important zoonotic diseases of domesticated animals?
1. Parasitic infection
2. Fungal infection
3. Bacterial infection
4. Viral infection
54
What does ubiquity mean?
Everywhere, microbes are everywhere
55
Where are the general places microbes can be found?
1. Soil
2. Air
3. Water
4. Human controlled industries
56
What microbes can be found in soil?
Saprophytes
57
What do saprophytes do?
Decompose organic matter such as rocks
Convert atmospheric nitrogen into a form that can be used by plants
58
What resource does water provide for microbes?
Important source of photosynthesis
59
Where are microbes on the food chain?
The beginning
60
Water acts as a __________ for many diseases.
Vector or reservoir
61
How do humans use water microbes?
Beneficial for sewage treatment to decompose organic matter
62
Why is air important for microbes?
Microbes are dispersed in the air
They travel through it
63
Why can't microbes lived in the air?
There are no nutrients in the air for the microbes
64
What do microbes affect?
Every organism and every system
65
What are the three things microbes can be?
1. Beneficial
2. Opportunistic
3. Pathogenic
66
How humans utilized microbes in industries?
1. Food production
2. Engineered products
3. Genetic engineering (insulin)
4. Research tools
67
What are the different types of microorganisms?
1. Bacteria
2. Fungi
3. Protozoa
4. Algae
5. Viruses
68
What are the two kinds of bacteria?
1. Prokaryotes
| 2. Archaea
69
Where are prokaryotes found?
Normal human/animal flora
On the skin, in the G.I. tract
Usually beneficial or harmless
70
What are pathogenic prokaryotes?
Organisms capable of causing disease
71
What are rickettsia?
Obligate intracellular parasites that must be inside eukaryotic cells to reproduce
72
How are rickettsia transmitted?
Buy arthropod vectors
73
What is an example of rickettsia?
Rickettsia rickettsii
Rocky Mountain spotted fever
74
What is chlamydiae?
Obligate intracellular parasite
75
How is chlamydiae transmitted?
Inhalation
| STD
76
Example of chlamydiae?
Chlamydia psittaci
In birds and humans
77
What are viruses?
Subcellular microbial agents
Not cells
Technically not alive
78
What is spontaneous generation?
Life came from nonlife
79
Example of spontaneous generation
Grain + rags = mice
80
What year did van Leeuwenhoek discover microbes?
1674
81
What was van Leeuwenhoek known for?
Creating the first microscope with various lenses
Using simple microscope observed "animalcules"
82
When was the golden age of microbiology?
1875 to 1900
83
What did the golden age of microbiology involve?
Germ theory of disease
Robert Koch's disease postulates
84
What is the germ theory of disease?
Theory that disease can be caused by microorganisms
85
What are the Robert Koch's disease postulates?
- Organism must be present in all cases of the disease
- must be able to infect a healthy animal with the organism and get the same disease
- if you culture organisms from both animals they should be the same
86
What are the shapes of microbes?
– Coccus (cocci)
– Bacillus, rod
– Helical, spiral
87
What shape are coccus or cocci microbes?
Round
88
What shape are bacillus or rod microbes?
Oval or elongated
89
What shape are helical or spiral microbes?
Bent or curved
90
What are the groupings/arrangements of microbes?
1. Chain- strepto
2. Bunches- staphylo
3. Pairs- diplo (cocci)
4. Palisade- rods
91
What is the structure of the cell membrane of prokaryotes?
Phospholipid by layer with embedded proteins
Hydrophilic heads and hydrophobic tails
92
What does a cell membrane do?
Separates interior of cell from surroundings
93
How do proteins interact with the cell membrane of prokaryotes?
Proteins act as channels and pumps to import and export nutrients, waste, etc.
94
What is selective permeability of a cell membrane of a prokaryote?
Limits the size of particles or charges of a particle that can pass through the cell membrane
95
What is a cell wall?
Tough outer protective layer of a cell
96
What is the cell wall of a prokaryote made of?
Mostly carbohydrates, some protein
97
What is unique about prokaryotes cell walls?
Peptidoglycan
98
How did the base layers and outer layers of gram-positive and gram-negative cell walls compare?
Base layer of both gram-positive and gram-negative are the same
Outer layers differ
99
What are the cell walls of gram (+) cells made of?
Peptidoglycan cell wall with teichoic acid
100
How do you gram (+) cell walls stain?
– Stains easily, hard to decolorize
101
What is a mordant?
Gram's iodine binds with the cell wall making it difficult to remove
102
How do gram (+) cell walls react to dry environments?
More resistant to drying out
103
How does the gram (+) cell wall react to penicillin?
Penicillin disrupts the synthesis of peptidoglycan and the cell wall leaks which causes the organism to die
104
What do you gram-positive cell walls produce?
Exotoxins
105
What are gram (-) cell walls made of?
Thin peptidoglycan base layer
Outer phospholipid membrane
No teichoic acid
106
How do you gram-negative cell wall stain?
– Harder to stain cell wall, stain has to penetrate lipids
– Easy to decolorize – alcohol is soluble in outer membrane
107
How do gram-negative cell walls react in dry environments?
– More susceptible to drying out
– Prefer moist environments
108
What are Archaea bacteria?
old, weird bacteria
| first life forms on a planet
109
Where are Archaea bacteria found?
- Deep Sea Hydrothermal Vents: boiling temperatures
| - Mountain Tops: freezing temperatures
110
What are the 3 examples of fungi?
1. yeast
2. dermatophytes
3. mushrooms
111
2 examples of Protozoa
- giardia
| - babesia
112
Why are Algae important?
important source of photosynthesis
113
What are viruses?
- smaller than bacteria
- not alive
- needs a host to "live"
114
What is the #1 medication prescribed by human and animal doctors?
antibiotics
115
How do pathogens pass between animals and humans?
- humans to animals
| - animals to humans
116
What is the problem with overprescribing prescribing antibiotics?
antibiotics can lead to bacteria resistant to antibiotics
117
What are Prokaryotes?
1. very simple structure
2. no nucleus or other internal organelles
3. small circular single strand of DNA
4. ancient organisms, believed to be the first life forms and precursors to eukaryotes
118
What are Eukaryotes?
1. more complex structures: nucleus
2. All DNA is located inside a nucleus
3. Includes all plants, animals, fungi, and protozoa
119
What is nomenclature?
traditional classification
120
What is the order for traditional classification?
```
Kingdom
Phylum
Class
Order
Family
Genus
Species
```
121
What are the 3 kingdoms and the 3 exceptions?
1. Bacteria
2. Archaea
3. Eukarya
4. Rickettsia
5. Chlamydiae
6. Viruses
122
What are the 4 different Eukarya?
1. Protists
2. Fungi
3. Plants
4. Animals
123
How do you gram (-) cell walls react to penicillin?
Fairly resistant to penicillin
124
What can be produced by gram-negative cells?
Endotoxins
125
How do gram-negative cells interact with its host?
– Small pieces of the outer layers can be toxic to host
– toxin is actually part of organism
126
What is the glycocalyx?
Gel like surrounding of some organisms
127
What are thick glycocalyx called?
Capsules
128
What are thin glycocalyx called?
Slime layer
129
What is the glycocalyx used for?
Used for attachment to surfaces and for resisting phagocytosis
130
What does the presence of a glycocalyx make an organism?
Can make the organism pathogenic
131
Example of an organism made pathogenic by a glycocalyx
Tuberculosis
132
How does a glycocalyx stain?
Hard to stain
Have to use a acid-fast stain
133
How does a glycocalyx protect the cell from the environment?
Prevents dehydration
134
How does the glycocalyx react with the host?
Causes antibody production by the host because it produces antigens
135
How is the cytoplasm of a prokaryote structured?
Fluid found in interior of cell
Contains all the cells genetic material and enzymes for metabolism
136
What surrounds the cytoplasm of a prokaryote?
Cytoplasmic membrane
137
What structures are bound to the inner surface of the cytoplasmic membrane of prokaryotes?
Enzymes
138
What are the structures found in the prokaryotic cytoplasm?
– Ribosomes
– Plasmid
139
What do you ribosomes do?
Protein synthesis
140
What is the plasmid of a prokaryote?
Small circular DNA strand of that is separate from the main DNA
141
What does the plasmid do?
Carries genes that are changed more frequently within the same generation
142
What is the R factor of a plasmid?
Carries genes for transferable drug resistance
143
What are flagella on a prokaryote?
Hair-like projections on cell surface that are made of protein
Too small to see with a light microscope
Can have more than one
144
How does the flagella of a prokaryote move the cell?
Spins rapidly to propel through surroundings
145
How does a prokaryote know where to move?
Chemo taxis is used to determine where they want to move
They can move towards or away from light, food, chemicals
146
What can be produced by the flagella prokaryotes?
Antigens
147
What are fimbriae of prokaryotes?
Similar to flagella, but smaller
Usually have many
Can be antigenic
148
What organism can become pathogenic with fimbriae?
E. coli
149
What are fimbriae used for in prokaryotes?
Use for attachment
150
What are pili of prokaryotes?
– Longer, hollow fimbriae
– Used in DNA exchange
– One or two per cell
151
What are endospores?
Very resistant structures, inactive seed
Only one per cell
Released when vegetative cell dies
152
What organisms can form endospores?
Gram (+) rods
Bacillus
Clostridium
153
How long can endospores survive in heat?
Resistant to boiling for one hour
154
What unfavorable conditions cause endospores to form?
– Heat
– Drying
– Lack of nutrients
– Oxygen
155
How long can an endospore stay dormant?
Can last for decades before germination/germinating
156
What is the difference between eukaryotic and prokaryotic cell walls?
Eukaryote cell walls don't have peptidoglycan
157
How is an animal cell wall constructed?
No cell walls, just membranes
158
How are plant cell walls constructed?
Have cellulose cell walls
Are rigid
159
How are fungi cell walls constructed?
Chitin cell walls
| Same as exoskeletons in insects and crabs
160
How is the eukaryote cytoplasm constructed?
Cytoplasm is not completely fluid
Has protein fibers that make up a cytoskeleton
161
What are the inclusions of the eukaryote cell?
- nucleus
- ribosomes
- mitochondria
- chloroplast
162
Where does the eukaryotic DNA sit in the cell?
In the nucleus
163
How many ribosomes are there in eukaryotic cells?
200 to 1000
More than prokaryotes
164
What does the mitochondria do?
Energy production
ATP
165
What organisms have chloroplasts?
Plants
| Chlorophyll in plants
166
What do you chloroplasts do?
Energy capture by photosynthesis
167
How are flagella in eukaryotic cells different from prokaryotic cells?
- much larger than prokaryotes
- eukaryotes do not have pili or fimbriae
- can be seen under a light microscope
168
How do eukaryotic flagella help the cell move?
Whip like motion to move
169
What are the cilia of eukaryotes?
Short flagella used for motility
Usually have many and cover the cell membrane
Use like oars for locomotion
170
What do the cilia in the trachea and long cells do?
Move debris up and out
171
What do all living things require?
Energy
172
What is photosynthetic energy?
Process of turning sunlight into glucose and energy
173
What organisms use photosynthetic energy?
- plants
- algae
- Cyanobacteria
174
How do you different plants use photosynthetic energy?
Various methods for different plants to produce glucose
Some can produce glucose in the dark but it requires energy
175
How does the cell use glucose?
Breaks down glucose to make other molecules the cell needs
176
How do you non-photosynthetic organisms get energy?
They get glucose directly or indirectly from photosynthesis
177
What energy is made from light?
ATP, NADH
178
What is NADH?
A coenzyme that contains energy originally stored in glucose
This energy can be transformed into ATP through aerobic respiration
179
What is chemosynthetic energy?
Energy produced by chemical compounds
180
What are chemoautotrophs?
Organisms that use inorganic compounds for energy
Sulfur, nitrate
CO2 for carbon source
181
Examples of chemoautotrophs
Mostly odd aquatic organisms
No pathogens
182
What are chemoheterotrophs
Organisms that require organic compounds for both energy and carbon sources
183
Examples of chemoheterotrophs
Most bacteria
All humans and animals
Pathogenic bacteria
184
What are the chemical compounds or nutrients used for energy for chemoheterotrophs?
1. Carbohydrates
2. Protein
3. Lipids
4. Vitamins
5. Inorganics
185
What do chemoheterotrophs use carbohydrates for?
Sugars and starches
Easily converted to energy
Glucose is the energy of choice
186
What do you chemoheterotrophs use proteins for?
Proteins are broken down into amino acids
Amino acids are used to make specific proteins that the cell needs
187
What do chemoheterotrophs use lipids for?
Stored energy
188
How do you bacteria produce lipids?
Bacteria make their own fat from sugar
189
What chemoheterotrophs use vitamins?
Some fungi such as yeast
Needed in wine production
190
What inorganics do chemoheterotrophs use?
```
Sulfur
Iron
Magnesium
Calcium
Sodium
Potassium
```
191
How do bacteria get nutrients?
By getting nutrients to pass through the cell membrane
Must digest into smaller molecules before ingesting
Some secrete enzymes into surroundings
192
How do you eukaryotes ingest food particles?
Diffusion through the cell membrane
Phagocytosis
193
Examples of organisms that use phagocytosis to ingest food
Amoebas, leukocytes
194
What does a host need to supply in order for bacteria to be successful in the environment?
Nutrients
195
What temperatures can bacteria live at?
Bacteria can live in a wide range of temperatures based on the range they grow best at
196
What are psychrophiles?
Organisms that do best that cold temperatures
Below 20°C
Refrigerator spoilage bacteria and a few pathogens
197
What are Mesophiles?
Organisms that live in moderate temperatures
Most bacteria and pathogens
Room temperature to body temperature: 25° to 37°C
198
What are thermophiles?
Organisms that live in 40°C or higher
Can survive pasteurization temperatures
Some food spoilage bacteria
199
How can temperature affect bacterial growth?
If the host can provide optimum temperatures in the bacteria will be successful
Manipulating temperature may help control bacterial growth
200
How does heat help control bacterial growth?
Heat works by denaturing enzymes
201
How does dry heat work against bacteria?
Desiccates and kills but takes a long time
Mini endospores are resistant
202
Why is moisture used to kill bacteria?
Steam is good for heat transfer
203
Moist heat is used in autoclaves at what temperature and for how long to sterilize?
250°F
15 to 30 minutes
204
How long does boiling take to kill bacteria?
Many hours to kill the spores
205
Why would canned foods need to be boiled?
To kill spores
Some bacteria can live in that environment and become endospores
206
What is pasteurization?
Use of high heat for short periods of time
207
What is flash pasteurization?
70 to 80°C
10 to 20 seconds
Used for milk and juice
208
What is bulk or vat pasteurization?
60 to 70°C
30 minutes
Wine
209
What is ultra pasteurization?
138°C
| 2 sec
210
What is ultra-high temperature pasteurization?
I 138 to 150°C
| 1 to 2 sec
211
What are obligate anaerobes?
Organisms that cannot live in oxygen
212
What are some examples of obligate anaerobes?
Clostridium botulinum
Clostridium pefringens
Clostridium tetani
213
What are obligate aerobes?
Requires oxygen to grow and live
214
What are facultative anaerobes?
Can grow/live with or without oxygen
Would prefer oxygen
215
Examples of facultative anaerobes
Most pathogens
E. coli
Salmonella species
216
What can be controlled by manipulating the amount of oxygen available?
Bacterial growth
217
What pH do most bacteria and pathogens do best at?
Neutral to slightly acidic
5-7.5
218
What pH do some non-pathogens require?
Strong acidic or alkaline pH
219
What do organisms produce to slow the growth of competitors?
Acids
220
By manipulating the pH of the environment we can control the growth of what?
Bacteria found in canned food and urine
221
What osmotic pressure do bacteria need?
Isotonic concentration of salts
~ 0.85% salt
222
How much salt is in seawater?
About 3.5% salt
223
What organisms can live in salt water?
Has its own population of organisms
Most terrestrial organisms can't live in saltwater
224
What increases with solute concentration of a cell?
Osmotic pressure
225
What does osmotic pressure do for the cell structure?
Keep cytoplasm firmly against cell membrane
Helps cell keep its shape
226
What is manipulated when salt concentration is changed?
Osmotic pressure
227
What can be controlled by manipulating osmotic pressure?
Bacterial growth
228
What is a hypertonic environment of a cell?
– Cell solute is low
– H2O leave cell
– Cell crenates or shrivels
– Cell can die
229
What is a hypotonic environment of a cell?
- cell solute concentration is high
- H2O enters cell
- cell bursts and dies
230
What are the phases of the bacterial growth curve?
1. Lag phase
2. Growth or log phase
3. Stationary phase
4. Death phase
5. Dormant phase
231
What is the lag phase of the bacterial growth curve?
No increase in numbers
from inoculation to constant growth phase
Adjustment period
232
What is the growth or log phase of the bacterial growth curve?
Low to high numbers very fast
Growth is very fast at a constant rate of multiplication
Easy to kill bacteria at this time
233
What is the stationary phase of the bacterial growth curve?
No loss of bacteria or gain of bacteria in terms of population
Definitely production numbers are equal
Bacteria are most resistant to antibiotics
234
What is the death phase of the bacterial growth curve?
Number of cells that die are higher than the number of cells being produced
235
What is the dormant phase of the bacterial growth curve?
Survivors of the death phase
Have a low metabolic rate and spores can be formed
The body can kill off the rest of these bacteria
236
What are the two types of metabolism?
Catabolism
Anabolism
237
What is catabolism metabolism?
Energy yielding reactions
Breakdown of nutrients or the capture of light for energy
238
How does an organism with a catabolic metabolism get energy?
From glucose
239
What are the two main routes of getting energy for a catabolic metabolism?
Fermentation
Respiration
240
What is fermentation?
Generates a net of two ATP per glucose
Produces metabolic waste products such as lactic acid and alcohol
241
Examples of organisms that use fermentation
Yeast and some bacteria
242
What is respiration?
Generates 38 ATP per glucose
Can occur with or without oxygen
243
How do aerobes use respiration?
Use oxygen to make water by removing hydrogen from glucose
244
How do anaerobes use respiration?
Uses sulfur or NO3 or other inorganic compounds to remove hydrogen from glucose
245
How do organisms with an anabolic metabolism get energy?
Biosynthesis
Manufacture of materials required for cell function or structure
Cells require specialized carbs and sugars
Glucose is broken down to make new sugars
246
How do cells with anabolic metabolism get and use proteins?
DNA can make proteins required by the cell
Proteins are broken down into amino acids and rearranged into the proteins in the cell needs
247
How does an anabolic cell produce lipids?
Manufactured from glucose
248
What is Direct Transmission?
acquiring a disease from close contact
249
Examples of Direct Transmission?
1. intimate contact
2. bodily fluids
3. touching skin
250
What is Indirect Transmission?
contact with a disease in the environment
251
Examples of Indirect Transmission?
1. Arthropod vector
2. contaminated bedding
3. airborne
252
What is horizontal transmission?
- Between members of the same species
- Within the same generation
- between friends and family
- not from mom to child
253
What is vertical transmission?
- Passing something from one generation to the next
- mom to child
- during pregnancy
254
What is a subacute disease?
Between acute and chronic
255
What is a latent disease?
Causative agent remains in active for a time but then becomes active to produce symptoms
Will become active when it wants to
256
Example of a latent disease
Shingles
257
Where does a latent disease stay dormant in the body?
Within the nervous system
| - sacral plexus
258
What is an infection?
Organism growing and multiplying inside host
259
What is a primary infection?
- Acute infection
| - causes initial illness
260
What is a secondary infection?
– Opportunistic pathogen
– Occurs after primary infection
– Weekend body defenses
261
What is a subclinical or inapparent infection?
- does not cause any noticeable illness
| - hosts are reservoirs and vectors
262
What happens when the host of a subclinical infection passes the disease?
host can be a carrier and give the pathogen to others but they will show signs and symptoms
263
What is bacteremia?
Bacteria present in the blood
| Most white blood cells are not active in the circulatory system
264
What is septicemia?
Bacteria present in the blood causing inflammation throughout the body
265
What is toxemia?
Presence of toxins in the blood
266
What is viremia?
Viruses in the blood
267
What is intoxication?
Disease that is caused by a toxin rather than the organism itself
268
What is nosocomial disease?
Acquired illness as a result of a hospital stay
269
What is an intermediate host?
Harbors a parasite for a short transition period and doesn't make the host sick
270
What is a definitive host?
Harbors parasite while it matures and possibly reproduces
Makes the host sick
271
What are risk factors?
Any condition that can increase the chance of infection
272
Examples of where risk factors are found
Could be factors of the infectious agent, host or environment
273
What is an incubation period?
Interval of time between when the host first contracts the infectious agent and when clinical signs and symptoms of the disease develop
274
What is an asymptomatic carrier?
Infected individual showing no clinical signs of disease but potentially infective to others
275
Examples of diseases that an asymptomatic carrier can have
Ringworm
HIV
276
What is morbidity?
Refers to the incidence of ill health in a population
277
What is mortality?
Refers to the incidence of death or number of deaths in a population
278
Exotoxins
Proteins produced by an organism secreted into the environment
279
What are some of the most toxic substances known?
1. Tetanus
| 2. Botulism
280
What are the three types of toxins?
1. Neurotoxins
2. Enterotoxins
3. Cytotoxins
281
What do you neurotoxins effect?
The nervous system
282
What do enterotoxins affect?
G.I. Tract
283
What do cytotoxins affect?
Cells
284
What are the controls and defense mechanisms for exotoxins?
1. Heat
2. Immune response by host body
3. Easily inactivated to make toxoids
285
How does heat affect exotoxins?
- 60 to 80°C
| - Will break down toxin
286
What are the immune responses by the host body?
Producing antibodies called antitoxins
287
How are exotoxins are easily inactivated to make toxoids?
Inactivated toxins that can be injected to create an immune response without causing the disease
288
What are the seven organisms capable of exotoxin production?
1. Staphylococcus aureus
2. Clostridium tetani
3. E. coli
4. Salmonella typhi
5. Vibrio cholerae
6. Clostridium botulinum
7. Bacillus anthracis
289
What is Staphylococcus aureus?
- normal skin flora
- enterotoxins
- gram (+)
- food poisoning
- TSST-1
290
What is clostridium tetani?
- tetanus
| - releases tetanus toxin
291
What is E. coli?
- E. coli: O157:H7
- Enterohemorrhagic toxin
- traveler's diarrhea
292
What is salmonella typhi?
Typhoid fever
293
What is vibrio cholerae?
Coleragen
294
What is clostridium botulinum?
Botulism
295
What is bacillus anthracis?
Anthrax
296
Where are in the toxins produced?
Lipid part of some gram(-) organisms
297
How can you remove endotoxins with heat?
Greater than 250°F for 30 minutes to remove from the tissue cultures
298
When our endotoxins toxic?
Toxic at high doses
299
What effect do endotoxins produce?
– Lower blood pressure, fever, shock
– Blood coagulation
– information, diarrhea
– Hard to remove from body
300
What do Leukocydines toxins do?
Kills white blood cells
301
How do Leukocydines kill WBC?
Upset leukocytes cell membranes
302
How do Leukocydines affection the host?
Decreases host resistance
303
What bacterias produce Leukocydines?
1. Pneumococci
2. Streptococci
3. Staphylococci
304
What do hemolysin toxins do?
Breaks down cells, especially red blood cells
Streptolysins
305
What are the bacterias that produce hemolysin toxins?
Streptococcus pyogenes
306
What is streptococcus pyogenes?
Normal throat flora
Overgrowth causes a problem
307
What do streptokinase toxins do?
Dissolves blood clots
Can cause internal hemorrhage
Use after heart surgery to prevent clotting
308
Example of streptokinase
Streptococcus pyogenes
309
What are the direct methods for counting and measuring microorganisms?
1. Plate count
| 2. Membrane filtration
310
What is a plate count?
Add measured amount of sample to growth media then count colonies that form
311
What can be measured on a plate count?
– Body fluid
– Tissue
– food
– water
312
How is a sample prepared in order to get countable numbers?
Has to be diluted
313
How do you measure the colonies on a plate count?
Count colonies and multiply by dilution factor to get original count
314
How long does a plate count take and how efficient is it?
- very slow, takes 1-2 days to incubate
| - fairly accurate if done correctly
315
What is membrane filtration?
Filter organisms onto a membrane with a grid
316
How do you count the organisms using membrane filtration?
Count organisms in a few grids and multiply by number of grids
317
How long does membrane filtration take and how accurate is it?
– Fast
| – Fairly accurate but counts dead organisms too
318
What are the indirect methods for measuring and counting microorganisms?
1. Turbidity
| 2. Luceferin
319
How is turbidity used for measuring microorganisms?
Measures cloudiness of sample
Only works for high concentrations
Used for clear fluids
320
What does Luceferin do?
detects presence of bacteria in foods or on surfaces
321
How does Luceferin work?
Measures ATP
322
Where is luceferin used?
Food processing centers
Operating rooms
323
Artificial passive immunity injections are used post-exposure to what?
1. diphtheria
2. tetanus
3. botulism
4. rabies
