Host Microbe interaction / Immunology (W5) Flashcards
(59 cards)
1
Q
Give two reasons for preventing microbes from entering food
A
- to prevent food spoilage
- to prevent food related illnesses
2
Q
How does fermentation preserve food
A
It inhibits spoilage bacteria to grow
it causes Lactic acid bacteria to grow, which produce lactic acid and therefore lowers pH so other bacteria can not grow
3
Q
what are the 7 types of infection
A
- Clinical
- Subclinical
- Localised
- Systemic
- Iatrogenic (nosocomial)
- exogenous
- endogenous
4
Q
Define clinical infection
A
infections with signs and symptoms
5
Q
Define subclinical infection
A
infections with pathogen but no symptoms
6
Q
Define localised infection
A
Infection that is confined to one area of the body
7
Q
Define systemic infection
A
infection spread to different areas of the body
8
Q
Define iatrogenic infection
A
infection is caught from a medical practitioner or intervention (hospital)
9
Q
Define Exogenous infection
A
infection contracted from external environment
10
Q
Define Endogenous infection
A
infection contracted from within human host (eg from mother to fetus)
11
Q
what are the 5 modes of disease transmission
A
- Contact transmission (direct or indirect physical contact)
- Common vehicle (food/water/airborne)
- Vectors
- Direct inoculation
- Intra-placental
12
Q
what are the 4 reservoirs for infectious agents
A
- Animate - healthy
- Animate - active disease
- Animate - convalescent
- inanimate
13
Q
What are the 2 types of epidemiological study and what do they mean
A
- Descriptive epidemiology - track disease using location, age ,time, occupation etc.
- Analytical epidemiology - identify cause, transmission and prevention
14
Q
what are the 4 classifications/ stages of disease infection within a community
A
- Endemic - constantly present in community
- Epidemic - widespread disease within a community, only occasionally present
- Pandemic - Widespread epidemic, across multiple communities
- Sporadic - widely scattered disease (singular, irregular, infrequent)
15
Q
define aetiology
A
cause of the disease
16
Q
define morbidity
A
number made ill
17
Q
define incidence
A
number of new cases over a given period
18
Q
define prevalence
A
number of cases at a given time (old or new)
19
Q
what are 3 factors that influence the spread of disease
A
- Virulence of the pathogen
- Pathogenic transmission mode
- Population susceptibility
20
Q
what are 3 characteristics of lymph vessels
A
- collect fluid from tissues and return it to blood
- Circulates in one direction
- Blind end tubes
21
Q
what are the 2 lymphoid organs in the primary classification and what are their roles
A
- Red Bone Marrow - site where B cells and pre-T cells are produced and B cells mature
- Thymus - site where T cells mature
22
Q
What are the Lymph Organ Classifications (Based on function)
A
- Primary - Pluripotent stem cells (bone marrow and thymus)
- Secondary - Site of most immune response (organs, tissues, lymphocyte recirculation)
23
Q
what are the 3 parts in the Secondary Lymph organ Classification (based on function)
A
- Organs (have a capsule) (lymph nodes and spleen)
- Tissues (no capsule) (lymphatic nodules, Tonsils, appendix, peyer’s patch)
- Lymphocyte recirculation (B+T cells move from one place to another, Immune response)
24
Q
what are the 4 roles of the immune system
A
- Maintain homeostasis
- surveillance (detect changes)
- Differentiate between self and non-self antigens
- Destroy non-self antigens
25
What is the difference between the innate and adaptive immune response
innate- non specific defence
Adaptive - response based on recognition of specific invader
26
Which of the Body defence mechanisms are innate and which are Adaptive
Innate :
- phagocytosis
- inflammation
- NK cells
Adaptive
- cell mediated
- antibody mediated
27
what are the 4 cardinal signs of inflammation
- redness
- heat
- pain
- swelling
28
what releases chemical mediators during inflammation
damaged cells and mast cells
29
what chemicals are released during inflammation
- histamine
- kinins
- complement
- prostaglandins
- leukotactic agents
- leukocytosis inducing factor
30
what 2 things do chemicals to do blood vessels during inflamation
- increase blood flow by vasodilation
- increase capillary permeability
31
what does leukotaxis cause during inflammation
- attracts WBCs to the area
- phagocytosis
- healing
- leukocytosis inducing factor (stimulates production + release of WBCs
32
What makes up the innate immune system's first line of defence
- Mechanical barriers
- Normal Flora
- Secretions
33
What makes up innate immune system's second line of defence
- serum
- White blood cells
34
what are the 3 antigen presenting cells
- macrophages
- dendritic cells
- B cells
35
what are the 3 types of lymphocytes and what percent of each of them are present in the body
- T lymphocytes (80%)
- B lymphocytes (15%)
- Natural Killer cells (5%)
36
what types of cells do natural killer cells kill
- host cells that are infected with virus
- cancer cells
37
What are the three types of T cells and what do they each do
T-helper (detect antigens and activate macrophages, Tc and B cells)
T-regulator (suppress the immune system when finished)
Cytotoxic T cells (Kill virus infected cells and cancer cells)
38
what mediates adaptive immunity
Lymphocytes
39
what is a key ability of Adaptive that Innate does not have
Memory
40
What are the two branched of the Adaptive immune system
1. Humoral immunity (antibody mediated)
2. Cell Mediated
41
what is an antibody
a specialised protein that recognises and attaches to its matching antigen
42
what cell makes antibodies
B lymphocytes
43
what are 2 names for the specific region on antigens that antibodies attach to
- Epitopes
- Antigenic Determinants
44
What are the key differences between the primary and secondary immune responses
Primary:
- has a several day lag
- antibody type is immunoglobulin M (IgM)
Secondary:
- much quicker response
- longer lasting
- antibody type is immunoglobulin G (IgG)
45
How are cytotoxic T cells alerted that a cell has been invaded
The invaded cell has a wide range of surface receptors against antigens. So when it is infected it will present the matching antigen so the Cytotoxic T cell can bind to it to destroy the cell.
46
How do natural Killer Cells know to kill the cell
There is reduced MHC 1 proteins on the surface of the cell
47
How do natural Killer cells kill cells
Antibody Dependant Cell Cytotoxicity
48
what 2 cells regulate the immune response
T-helper cells - stimulate
T-regulatory cells - inhibit
49
what is administered for Active and Passive immunity and how long to the last comparatively
Active = antigen, longer lasting
Passive = antibody, shorter lasting
50
what are the 2 fields of the commercial uses of microorganisms
1. Food microbiology
2. Industrial microbiology
51
what 5 things cause food spoilage
- insect or rodent infestation
- physical damage
- chemical damage
- microbial growth
- Enzyme activity
52
what is the name for aerobic and anaerobic spoilage
aerobic = decay
anaerobic = putrefaction
53
how (3) can diseases be aquired from food
- direct effects of microbes
- toxins
- microbial effect on food
54
What are the 3 major approaches to food preservation
1. prevent microbial contamination
2. inhibit microbial growth and activity
3. destroy / remove microbes from food
55
what are 5 reasons why we treate waste
1. to remove pathogens
2. to remove toxins
3. to prevent contamination of drinking water
4. to prevent foul odours
5. remove nutrients that cause pollution
56
what does BOD stand for and what does it mean
Biochemical Oxygen Demand
it is a test that determines levels of biological, degradable organic matter that is present in water
57
what does high BOD indicate
high levels of organic matter in water
58
what are 3 uses for bacteriophages
1. recombinant DNA technology
2. to identify pathogenic organisms
3. possible treatment for bacterial infections
59
what are the 3 stages of wastewater treatment and what do they entail
Primary
- removal of large solids
Secondary
- microbial digestion of organic matter
- hydrolysis
Tertiary
- Physical and chemical methods
