Exam 3 Flashcards
1
Q
microbial ecology
A
the study of microbes in their natural environment
2
Q
Challenges to studying microorganisms
A
most information comes from information obtained through molecular techniques
3
Q
biotic factors
A
any living or dead organisms that occupy a habitat: plants
4
Q
abiotic factors
A
non-living components such as minerals, water, temp, and light that affect growth
5
Q
biosphere
A
all physical locations on earth that support life
6
Q
hydrosphere, lithosphere, atmosphere
A
water, soils, air
7
Q
Characteristics of climatic regions
A
communities (different populations living together), populations (all the same kind)
8
Q
habitat
A
physical location and environment to which an organism has adapted
9
Q
niche
A
overall role that species or population serves in a community
10
Q
microenviorment
A
Microorganisms habitat
11
Q
producers
A
top of food chain, provide fundamental energy source that drives food chain: alge
12
Q
consumers
A
second on food chain: feed on other living organisms, ex: grazers, carnivores
13
Q
decomposers
A
3rd on food chain: break down and absorb the organic matter of dead organisms: soil bacteria
14
Q
biochemical cycles
A
complex systems that rely on the interplay of primary producers, consumers, and decomposers
15
Q
why recycling is important in biochemical pathways
A
maintains necessary balance of nutrients in the biosphere so that they do not build up or become unavailable
16
Q
carbon cycle
A
regulates Earth’s climate, and supports life by providing carbon for essential molecules
17
Q
carbon cycle recycling
A
Recycled through ecosystems via carbon fixation, respiration, or fermentation
18
Q
nitrogen cycle
A
ensures the availability of nitrogen
19
Q
reactions in nitrogen cycle
A
nitrogen fixation, nitrification, denitrification, ammonification
20
Q
Microorganisms associated with root nodules
A
rhizospheres and interact with microbes in a synergistic way
21
Q
Sulfer cycle
A
fuels microbial metabolisms, regulating Earth’s redox state
22
Q
Phosphorus cycle
A
integral part of DNA, RNA, and ATP
23
Q
Phosphorus cycle found and cycled
A
cycled in abiotic and biotic environments: found in biosphere, rocks and sediments
24
Q
humus
A
slowly decaying organic litter from plant and animal tissues, important for microbes to decompose the litter and recycled material
24
aquifer composition and distribution
deep groundwater source of water, circulates slowly, resurfaces through springs, geysers, and hot vents
25
bacteriophages in the environment
can swap and exchange microbial genes play a role in evolution
26
different types of plankton and role
phytoplankton: photosynthetic algae and cyanobacteria zooplankton: microscopic consumers such as protozoa and invertebrates
27
red tides
harmful algae blooms
28
eutrophication
aerobic heterotrophs that deplete oxygen by decomposing organic matter
29
Bioaccumulation
accumulation of pollutants in higher concentrations as they move up the food chain
30
2 example of microorganisms that have increased incidence due to climate change
malaria- deforestation, hantavirus- population growth of deer mouse following El niño in 1993
31
Epidemiology
Monitoring and controlling disease occurrence to promote PH
32
Infectious disease
an illness caused by a pathogen
33
sporadic case
diseases that are isolated infections in a particular population
34
Difference between pandemic and epidemic
pandemic spreads to multiple countries, epidemic occurs in a specific region at a specific time frame
35
emerging vs reemerging pathogens
Emerging- newly identified agents that were only caused by sporadic cases, reemerging- infectious agent that was under control but is resurfacing
36
Zoonotic disease
spread from animals to humans
37
communicable vs contagious diseases
communicable- transmit human to human, contagious- easily transmitted from one host to the next
38
signs vs symptoms
signs- objective indicators can be measured or verified (fever, rash)- symptoms- sensed by patient (pain, fatigue)
39
how diseases characterized by onset and duration of symptoms
acute disease and chronic diseases
40
koch's postulates
4 criteria used to evaluate with pathogen is causative agent
41
koch's postulates limitations
certain infectious diseases cannot be isolated, some microbes becomes attenuated in pure cultures, some microbes do not infect non-human hosts
42
Reservoirs
are an animate or inanimate habitat where the pathogen is naturally found
43
potential sources of infection
endogenous source: pathogen came from host's own body-- exogenous source: pathogen is external to the host
44
modes of transmission
indirect (vector) and direct (door knob)
45
infectivity, virulence, pathogenicity
1. describes how good an infectious agent can infect
2. describes severity of disease following infection
3. general ability of infectious agent to cause disease
46
5 stages followed infectious diseases
incubation period, prodromal phase (early symptom development), acute phase (peak), period of decline, convalescent phase
47
2 goals of epidemiology
describe and intervene
48
epidemiological triangle
environmental factors, etiological agent, host factors
49
quarantine
short incubation times, recommended when a person has cholera, TB, plague, smallpox, yellow fever
50
vector control
limiting numbers of biological vectors helps prevent spread
51
rate, ratio, proportion
1. used to measure occurrence over time
2. occurrence of an event in one group as compared to another group
3. % of a whole
52
incidence rate
number of new cases in a defined population during a defined time frame
53
Mortality rate
number of deaths during a specific time period
54
measures of association
tell us what factors may be linked with cases of disease and who might be at risk
55
Descriptive epidemiology
goal is to describe the occurrence and distribution of disease
56
Analytical epidemiology
investigates what caused disease, why people get disease, and how disease is prevented and treated
57
case reports
Individual or groups records of a disease
58
cross-sectional studies
evaluate exposure and development of disease and defined population at a single point in time
59
hospital epidemiology
Involves the surveillance, prevention, and control of healthcare-acquired infections
60
HAIs
disease that develop in a healthcare setting
61
common HAIs
CAUTIs, pneumonia, surgical wound infections
62
Notifiable and reportable diseases
states have laws requiring reports of certain diseases to local health authorities
63
factors contributing to emerging and reemerging diseases
population growth, poverty, deforestation
64
eradication vs disease control
Eradication means that there are no longer any cases in the world
65
good candidates for eradication
strong social and political support
66
main characteristics of protozoa
Unicellular, EU, chemoheterotrophic
67
reproduction of protozoa
sexual reproduction occurs in some conjunction
68
Conjugation steps
two paramecia conjugate, 3-4 haploid undergo mitosis, paramecia donate to each other, nuclei in each cell are genetically different, new diploids divide
69
mechanisms of survival inside a host
protective coverings (cysts, tough outer walls), dormancy, environmental dispersal
70
protozoa from each phylum
archaezoa ( giardiasis), microspora (chronic diarrhea), amoeboza (PAM-fatal brain infection), apicomplexa (malaria), ciliophora (balantidiasis), Euglenzoa (chagas)
71
mechanisms of infection for giardia
fecal-oral transmission, ingestion of cysts, upper small intestines, multiply by binary fission, encysts before
72
trichomonas vaginalis
sexually transmitted infection, interfaces with host immune system and vaginal microbiota
73
E. Histolytica transmission
Ingestion contaminated food/water, mature cysts, excystation, trophozoite, excystation, immature cysts, mature, excretion through feces
74
E. Histolytica susceptibility to disease
host genetics, young age, malnutrition
75
3 free-living amoebas
Naegleria flowleria (people who swim in warm natural bodies of water; nasal passages), Acanthamoeba (invades broken skin), B. mandrillaris (open wounds and nasal passages)
76
Cryptosporidium vs Toxoplasma
Cryptosporidium fecal-oral route, in small intestine, self-limiting diarrhea
Toxoplasma- foodborne illness and fecal-oral route
77
American vs African sleeping sickness
American- Kissing bug, parasite enter wounds after bites, chronic disease: African- Tsetse fly, injects parasite directly into blood stream, acute and neuro disease
78
main characteristics of helminths
multicellular EU, digestive, circulatory, nervous, excretory, and reproductive systems, some specialize to live inside hosts
79
2 phlya of helminths
platyhelminthes (flatworms), Nematoda (roundworms)
80
definitive host
host in which adult worm reproduces sexually
81
Intermediate host
host that harbors a parasite that grows but is not up to its sexual maturity
82
Characteristics of Trematodes
have ventral and oral suckers, cuticle (nutrients are absorbed through here)
83
Characteristics of cestodes
scolex (head)- has suckers or hooks, body segments, contains male and female reproductive organs
84
Taenia
Tapeworm, occurs when humans ingest tapeworms eggs rather than infected meat
85
Characteristics of nematodes
have a complete digestive system, dioecious (male and female reproductive organs in different worms)
86
Ascaris, Trichuris, Hookworms
small intestine and 200,000 eggs/female, caecum and colon and 3000-5000 eggs/female, upper small intestine 9000-10000 or 25000-30000 eggs/female
87
Bartonella
cat-scratch disease, bite or scratch by a cat or dog that results in a swollen lymph node
88
Ehrlichia
Tick-borne disease that causes flu like symptoms 1-2 weeks after tick bite
89
Beneficial bacteria to plants
nitrogen-fixing bacteria- Azospirillum (soil) and Rhizobium (roots)
90
non-beneficial bacteria to plants
agrobacterium: can insert DNA into plants cells, causes tumorous growths
91
2 species of Neisseria species of PH importance
N. meningitdis and N. gonorrhoeae
92
cause of pathogenesis in infection with Bordetella
causative agent is B. pertussis toxin production (whooping cough)
93
pseudomonas infections
opportunistic pathogens (swimmers ear), metabolically diverse, produce fluorescent pigments
94
life cycle factors of legionella that makes them easy to cause infections
can live in water plumbing systems, can make biofilms, can live in natural aquatic environments and man-made systems, undergo phagocytosis
95
Virbio species
Vibrio cholerae- causes cholera, V. parahaemolyticus - cause gastroenteritis
96
Campylobacter species
Vibrio with polar flagella
C.festus- causes spontaneous abortions in domestic animals: C.jejuni- leading cause of outbreak of food borne intestinal diseases
97
Characteristics of Clostridium
endospore producing, obligate anaerobes: Tetanus, Botulism, C. diff
98
clinical entities associated with Helicobacter infection
Multiple flagella
Peptic ulcers, stomach cancer (oncogenic bacterium)
99
why is B. anthracis one of the most dangerous bacteria to humans
anthrax- produces exotoxin lethal to humans, highly resistant endospores, multiple routes of infection
100
staphylococcus spp. important?
common infections of surgical wounds in hospitals (HAIs), has the ability to quickly develop resistance to antibiotics
101
diseases associated with streptococcus
Meningitis, pneumonia, sore throats, cavities
102
3 types of hemolysis
alpha (incomplete hemolysis), Beta (complete hemolysis), Gamma (Nonhemolytic)
103
what is hemolysis
toxin which lyse red blood cells
104
Characteristics of Scarlett fever
occurs in <10% of streptococcal pharyngitis cases, most common in children under 10, important to treat to prevent possible serious complications
105
how does S. pyogenes induce immunity
M proteins can trigger the body to make antibodies that attack S. pyogenes, but can also cross react with our proteins
106
bacteria associated with otitis media (bacterial complication of colds)
Streptococcus pneumoniae, Moraxella catarrhalis, non-typable Haemophilus influenzae
107
bacteria associated with acne
propionibacterium acnes
108
Mechanism of pathogenesis for acne
sebum and dead skin cells block pores, P.acnes proliferative in clogged pores, inflammatory response
109
what is impetigo
highly contagious skin infection caused by bacteria (staphylococcal)
110
Characteristics of impetigo
highly contagious, secondary bacterial infections are possible
111
species associated with human meningitis
haemophilus, meningococcal, listera
112
what characteristics of the human body prevent pathogens from entering the CNS
Blood-brain-Barrier: deliver nutrients and oxygen to CNS, allow only few type of molecules to pass through capillaries, only very small cells can pass through
113
mechanism of pathogenesis associated with listeria monocytogenes infection
1. enters cell through phagocytosis and breaks out of phagosome, enters cytoplasm
2. reproduces in host cell staying safe from antibody mediated immune response
3. bacterium creates tail for propulsion and propels to neighboring cell, enters cytoplasm
4. new cells are infected same way
114
Koch's Postulates
1. Microorganism must be found in abundance in all organisms suffering the disease, and not in healthy ones
2. Microorganisms must be isolated from a diseased organism and grown in a culture
3. the cultured microorganism must cause disease when introduced into a healthy organism
4. Microorganism must be re-isolated and inoculated
115
Encystment
protective capsule, allows protist to live in harsh environments, allows parasites to live outside host
116
Giardia mechanism of disease
Ingestion of cysts through contaminated food or water, encystation --> Trophozoites--> replication, Infected cysts passed through stool, infects food and water
117
Trichomonas Vaganillas mechanism of diease
Sexual intercourse, trophozoite enters vaginal wall and urine , multiply by binary fission, trophozoite now in vagina or urethra
