Disease and immune system Flashcards
1
Q
Bacterial Diseases
A
- TB
- Bacterial Meningitis
- Ring rot
2
Q
Viral Disease
A
- Influenza
- HIV
- TMV
3
Q
Fungal Diseases
A
- athletes foot
- black sigatoka
- ring worm
4
Q
Protoctista Diseases
A
- Malaria
- Potato and tomato late blight
5
Q
Direct transmission
A
- by touching
6
Q
Indirect transmission
A
- from air, water, food or by a vector
7
Q
Climate factors
A
- Malaria
8
Q
Social factors
A
- TB = overcrowding and inadequate housing
- HIV = sharing of needles or bodily fluids
9
Q
Plant defences
A
- chemical
- physical
10
Q
Physical defences
A
- waxy cuticle
- cell wall
- production of callose
11
Q
Chemical defences
A
- antimicrobial chemical which can kill or inhibit growth
- e.g saponins and phytoalexins
12
Q
Non - specific defence mechanism in animals
A
- skin (acts a barrier)
- mucus membranes (protect body openings)
- blood clotting ( plug wounds)
- expulsive reflexes (coughing ans sneezing)
- inflammation ( isolate any pathogens)
- wound repair (skin repairs itself)
13
Q
Immune system
A
- response to a foreign object
- non-specific or specific
- non-specific = same for everyone
- specific = involves T and B cells
14
Q
Phagocytes
A
- macrophages
- neutrophils
15
Q
Phagocytosis
A
- pathogen produce chemical that attract phagocytes
- phagocyte recognises the non - human protein on the pathogen
- phagocyte then engulfs ( inward folding of the membrane) and encloses the pathogen into a vesicle ( phagosome)
- phagosome binds with a lysosome forming a phagolysosome
- that then injects digestive enzymes to destroy the pathogen
- the macrophage then forms an antigen presenting cell (APC)
16
Q
Cytokines
A
- produced by phagocytes
- acts as cell signalling molecules
- tell other phagocytes to go to the site of injection
17
Q
Opsonins
A
- chemicals that bind to the pathogens
- make them more recognisable to phagocytes
18
Q
T helper cells
A
- produce interleukins to activate B cells and killer T cells
19
Q
T killer cells
A
- destroy the pathogen
- contain hydrolytic enzymes
20
Q
T memory cells
A
- part of the immunological memory
21
Q
T regulatory cells
A
- supress the immune system
- stops them from attacking own body cells
22
Q
Plasma B cells
A
- produce antibodies
23
Q
Memory B cells
A
- provide immunological memory
24
Q
Cell mediated response
A
- APC fit the receptors of helper T cells which become activated and produce interleukins
- stimulates more T cells to divide by mitosis
- they divide for form clones of the helper T cells which have the correct antigen to bind to the pathogen
- can form T memory cells, interleukins to stimulate phagocytosis or stimulate B cells to divide, develop into killer T cells
25
Interleukins
- stimulate phagocytosis
- produces by helper T cells
- Cytokines produced by T helper cells
- stimulate B cells.
26
Humoral immunity
- B cell with complementary antibodies to the antigens of the pathogen bind and the pathogen is engulfed forming a APC
- activated T helper cells ( from cell mediated response) bind to the B APC cell = clonal selection
- The activated B cells divide by mitosis to produce plasma cells and B memory cells = clonal expansion
- cloned plasma cells produce antibodies which fit to the pathogen antigens = primary immune response
27
Secondary response (humoral response)
- memory cells
- circulate in the blood with readiness to respond to a future infection by the same pathogen
- divide and form plasma cells to produce antibodies
28
Antibodies
- Immunoglobulins produced by B-lymphocytes in response to a specific antigen,
triggering an immune response.
29
Structure of antibody
- antigen
- light chain
- heavy chain
- hinge region
- constant region
- variable region
30
Hinge region
- allows for flexibility
31
Constant region
- bind to receptors
32
Variable region
- antiody - antigen binding site
33
Action of antibodies
- agglutination
- neutralising toxins
-preventing the pathogen from binding to the active site
34
Agglutination
- bind two pathogens at the same time
- easier to be engulfed by phagocytes
35
Neutralising toxins
- anti-toxins bind to toxins produced by the pathogens
- prevents further infection
36
Preventing the pathogen binding to cells
- block cell surface receptors so can't bind to host cells
37
Primary response
- enters body for the first time
- slow response
- B and T cells activated
- symptoms
38
Secondary response
- enters the body for the 2nd time
- fast response
- memory cells activated
- no symptoms
39
Immunity
- active natural
- active artificial
- passive natural
- passive artificial
40
Active natural
- e.g measles/ chickenpox
- Resistance that has developed through the production of specific antibodies
- It provides long-lasting immunity as memory
cells are produced.
41
Active artificial
- immune response after having a vaccine
- e.g covid-19
- contains antigens
42
Passive natural
- e.g baby to mother through placenta
- Resistance that occurs via the transfer of antibodies.
- It provides short-term immunity as no memory cells are produced
43
Passive artificial
- antibodies form something else
- e.g tetnus
44
Autoimmune disease
- e.g lupus (attacks connective tissues)
- cant recognise self antigens
- damages healthy body cells
- immune response against own body cells
45
Vaccines
- dead or weakened version of the pathogen
- antigens from a harmless toxin or pathogen
46
Herd vaccination
- immunity for all
- decrease chance of outbreaks
- e.g MMR, polio
- typically given in childhood
47
Ring vaccination
- new disease reported
- vaccinate those in vicinity
48
Personalised medicines
- tailored to individual DNA
- increased effectiveness of drugs
49
Synthetic biology
- make artificial proteins from technology
- e.g bacteria to destroy cancer cells
50
Antibiotic resistance
- comes from natural selection
51
MRSA
- causes wound infections
- resistant to several antibiotics
52
Clostridium difficile
- infects the digestive system
- resistant to antibiotics
- can cause fever, diarrhoea and cramps
53
Source of drugs
- from microorganisms
- key research for maintaining biodiversity
