Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MLSC 1009 Clinical Micro > Module 1 > Flashcards

Module 1 Flashcards

1
Q

Homeostasis

A

all mechanisms by which an organism responds to normal and abonormal conditions in a way that preserves a stable internal environmnet

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

Symptoms

A

subjective, experienced, and desriable characteristics reported by an individual

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

Signs

A

objective, observable, physical characteristics detected by a physician and technological aids

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

Disease

A

can range from health to morbidity and from acute to chronic

can be sub-clinical
- an individual may be infected and develop immunity to the infectious agent without been symptomatically ill; still a reservoir

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

Defence Mechanisms against Infection

A

1) Host surface defences (non-immunologic)
2) Inflammatory reaction (non-specific response)
3) Immunologic defence (specific)

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

Host Surface defences

A

Are a primary barrier to the vast majority of microbes in our environment

Include:

  • mucus (traps organism)
  • coughing/peristalsis/micturition (eliminates organisms)
  • high rate of epithelial cell turnover (sloughing off of skin cells eliminates skin organisms)
  • local disinfectants (tears, gastric acid, fatty acids in skin)
  • normal microbial flora
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Inflammatory response

A

Once a infectious agent bypasses the surface defence, a non-specific response is set in motion

In a pyogenic (pus producing) response, polymorphonuclear white blood cells (PMNs) attach the infectious agent and attract more PMNs and monocyte-macrophages

Rise in temperature is due to cytokines, tumor necrosis factor and interferon produced by the interacting, responding phagocytic cells as well as vasodilation. This is termed as pyrogenic (fever)

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

Immunologic defences

A

Specific towards invading pathogen due to immunoglobins and T-lymphocytes

Immune repsonse usually requires interaction with non-specific defence components (ie. complement and phagocytic cells)

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

Recognizing self from non-self

A

During embrogenesis, T cells undergo an education process in which antigens of the major histocompatibility classes (MHC) within the human leukocyte antigen complex (HLA) come to recognize self; programmed to respond to non-self antigens

If self-antigens are seen as non-self, the harmful response is auto-immune

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

Cells of the immune system

A

Lymphocytes (B, T, and natural killers), mononuclear phagocytes (monocytes/macrophages-antigen processing/presenting cells) and granulocytes (including neutrophils)

Lymphocytes

  • activated by macrophages
  • differentiate into T cells with specific activities (cytotoxic, memory)
  • activate B ells (proliferate into memory B cells or differentiate into plasma cells which produce antiibodies against foreign antigens)

Through interaction and secretion of soluable substances, these cells regulate the immune system, inflammation and functions in other tissues and organs

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

Antigen Elimination

A

Toxin neutralization: antibodies produced against toxins (ie. anti-toxin)

Virus neurtalization

Bacterial opsonization: Bacteria become coated with opsonins (primarily antibodies and complement) and are cleared by macrophages

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

Complement

A

Functions:
-lysis of cells, bacteria, and enveloped viruses
opsonization process mediattion to increase particle clearance
generation of peptide fragements that regulate feautures of the inflammatory and immune response (vasoldilation, phagocytic adherence and egress) to clear infections

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

Mutualism

A

Host and parasite benefit

Ex: E.coli in gastrointestinal tract; GIT produces vitamin K

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

Parasitism

A

One benefits and other is harmed

ex: roundworms

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

Commensalism

A

One benefits and the other is unaffected

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

Germ theory

A

regarded microorganisms as foes (parasitism) that caused disease

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

One microbe-one disease

A

In 1890, investigators went on a quest to ID infectious disease microorganisms but discovred a whole array that grew in culture; realized that they should be preset and their absence would be as significance as the presence of a known pathogen

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

The human microbiome

A

comprised of 100 trillion microbes that live on and in us, and the genes they contain

we aquire them through contact with people and food and environment, starting at brith with mom and her milk (continueing in a process of mutual selection during first 2 years)

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

Why is antibiotic resistance such a problem

A

If one bacterium evolves resistance to antibiottics, the responsible gene can be transffered to other bacteria, rendering them resistant too.

Because the microbiome can change more quickly than the human genome, the microbiome provides a much more rapid means for humans to adapt and thrive when environmental conditions change

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

Colonization

A

Occurs when microoganisms persis on the body surface

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

Transient colonization

A

At birth, transient colization occurs due to flora from the birth canal or in the mothers skin flora (c-section)

These survive but do not multiply

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

Normal Flora

A

Exist on all surfaces of the body exposed to the environment

  • unique to enviornment in which it grows
  • gut microbiome fluctuates in response to diet
  • is protective: imbalances in the relative amounts of these micoorganisms or a decrease in the absolute amount often preceds infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Nosocomial Colonizaton

A

refers to transient colonization with hospital or institution (long term care facility)

  • usually resistant to antibiotics
  • virulent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Carriers

A

Are those individuals colonized with organisms that are not considered normal flora but are not presently causing the host carrier any damage

considered potential reservoir for inection of others and may occur following a resolved systomatic infection and/or a sub-clinical infection

25
Q

Commensals

A

Normal flora organisms - may be opportunistic pathogens causing endogenous infection

usually when introduction of commensals into sites that should be sterile

-virulent

26
Q

Patterns of infectious disease (timeline)

A

1) exposure
2) incubation
3) prodromal
4) acute
5) decline
6) convalescene

27
Q

Exposure

A

disease can be contagious through all five phases of disease

28
Q

Incubation

A
  • no visible symptoms but communicable
  • incubation times varies
    carriers
  • individuals can remain asymptomatic but do not clear the pathogen; others become carriers post-illness
29
Q

Prodromal

A

genetic malaise, symptoms are non-specific

30
Q

Acute

A

Specific symptoms reach peak

31
Q

Decline

A

infection declines and disease resolves

32
Q

Convalescence

A

Patient regains strength

33
Q

Sources of infection

A

1) congenital
2) Exogenous
3) Endogenous

34
Q

Congenital

A

present at birth (often before)

  • Treponema pallidum (causes syphilis); example of transplacental infection; can cause birth defects or death
  • Group B streptococci, listeria monocytogenes are examples of bacterial agents that may be vertically transmitted to baby
35
Q

Exogenous

A

Source of infection is external to the host

  • organisms are aquired from a variety of reservoirs
  • person to person, animals, soil, water, food, hospital
  • organisms are transmitted: directly (communicable or zoonotic), indirectly (vectors, inhalation, ingestion
36
Q

Endogenous

A

the source of infection form within the host
- normal flora may cause disease if: its virulence increases, hosts immunocompetence ecreases, enviornment is altered, or introduced to new habitat where it doesnt belong

37
Q

Barriers to infection

A
  • physical: keratin, mucous, flushing
  • chemical: interferon, lysozymes, stomach acid
  • cellular: cilia, phagocytes, pyogenic-response
  • humoral: antibodies
  • biological: normal flora
38
Q

Virulence Factors

A
  • adaptation to specific sites
  • chemical signal molecules used in communication with other bacterial species
  • adherence factors
  • enzymes
  • capsules
  • toxins: endo (cell wall component of gram negative organisms released on bacterial lysis and death) and exo (released by organism into environment)
  • adaptation
39
Q

Endemic

A

Endemic disease is either cyclic (expected) or continuous but confined to a defined geographic location and affects small numbers of population

ex. california flu

40
Q

Epidemic

A

attacks many people at the same time in the same location or the same population for a period of time

ex. cholera

41
Q

Pandemic

A

are epidemics that have spread over a very wide are

they attack the majority of the population in a large area

42
Q

The Micro-ologies

A

1) Bacteriology
2) Mycology
3) Parasitology
4) Virology

43
Q

Mycoplasmas

A

Bacteria

  • no cell wall but have cell membrane
  • cant gram stain
  • smallest free-living forms
  • fastidious: culture is possible but difficult
  • cultured by special media
44
Q

Rickettsiaceae

A

obligate intracellular parasites that cannot be cultured

risk group 3; highly infectious

do not gram stain

spread by arthropods (ticks, fleas)

45
Q

Chlamydiales

A

infective form (elementary body)

reproductive

non-infectious growth from reticulate body &
inert

do not stain

cannot be cultured; have an unusual life cycle

obligate intraceullular parasites

46
Q

Mycology

A
  • study of fungi
  • candida albicans
  • reproduce by budding
47
Q

Parasitology

A
  • study of parasites

- Giardia lamblia

48
Q

Virology

A

Study of viruses

  • non-cellular
  • require host to reproduce
49
Q

Taxonomy

A

study of systems by which living organisms are placed in a group

1) Classification (arranges bacteria into groups)
2) Nomenclature (labelling of organisms); binomial system
3) ID

50
Q

Bacterial Genetics

A
  • have a singular, circular, double-stranded DNA chromosome that is not associated with histones
  • plasmids can replicate independently of the chromosome (autonomous replication)
  • plasmids may contain trasnposable elements and plasmids may insert into the chromosome
  • genes can be chromosomal (more stable) or extr-chromosomal (plasmids and transposable elements)
51
Q

Replication (bacteria)

A

Reproduction by asexual binary fission

  • single cell elongates, DNA replicates, cross wall forms, and 2 identical daughter cells are formed
  • rate at which cells double will determine size of the colony we observe ; colony size is primarily an expression of generation time (ie. rate of replication)

DNA replication
- supercoiled DNA relaxes, strands seperate at point of origin, parent strand acts as template and DNA polymerase builds, replication terminates at fork

rate is proportional to available nutrients and inversely proportional to build up of toxic waste

52
Q

Regulation of gene expression

A
  • gene expression may be constituitive (metabollically essential process)
  • inducible (in response to a stimulus in the enivornment, either the presence of a substrate or the depletion of a substance which when present, acts as a gene repressor)

or
- consituitive-inducible (always present but accelerates with the appropriate stimulus)

53
Q

Chronic Ilnnes

A

refers to persistence, not severity of symptoms

54
Q

Prokaryotes

A
  • cell envelope: complex cell wall with peptoidoglycan; plasma membrane no CHO or sterols (exception-sterols in myoplasmas)
  • gemone: no nucleus; single, circular chromosome & usually addition genetic material extrachromosomal (plasmids)
  • ribosomes 70s= 50S/30s
55
Q

Extrachomosomal elements

A
  • is in plasmids, insertion sequences, transposons, and integrons
  • importance: ability for transfer of antibiotic resistance between bacteria
56
Q

Insertion Sequence

A

code for movement of genes

57
Q

Transposons

A

have functional genes

must be inserted into plasmid to replicate but can be transferred

58
Q

Integrons

A

to provide a convient insertion site for antibiotic-resistance genes from foreign DNA sources

  • cannot replicate autonomously
  • capture gene cassettes
  • code for ABX resistance
  • cassettes shuffled in response to stimulus (exposure to ABX)
  • require transposition proteins for transfer

MLSC 1009 Clinical Micro (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions