Disease Flashcards
Explain the process of phagocytosis
Pathogens release cytokines which attract phagocytes
Opsonin proteins attach to pathogens which mark them
Phagocytes receptors attach to antigens on pathogens and engulf them and enclose them into a phagosome vesicle
Phagosome fuses with lysosome which contain powerful hydrolytic lysozyme enzymes
Lysozyme hydrolyse phagocyte into glucose and soluble molecules which are absorbed by the cytoplasm of the phagocyte
What are non specific examples of disease
Skin contain skin flora which outcompetes pathogens for space on skin
Blood clots which is a mesh of protein fibres and plugs wounds to prevent pathogen entry and blood loss
Mucous membranes - mucus trap pathogens and cilia sweep them away from lungs
Expulsive reflexes + Inflammation
What types of diseases can:
-Bacteria
-Viruses
-Protoctista
-Fungi
cause?
Bact - TB, ring rot
Viruses - HIV/ AIDS, Influenza, TMV
Protoctista - Malaria, tomato late blight
Fungi - Black Sigatoka, ( plant ), Athletes foot (animal)
What are plant defences again pathogens?
Waxy cuticle to prevent entry ( cell wall if it does not work)
Plants produce callose which is deposited between cell wall and plasma memb.
Plants produce antimicrobial chemicals
What are the living conditions which make transmission of pathogens more likely
Hot climates
Social factors - poorer sewage/ infrastructure and lack of fresh food and water
what are ways antibodies work
Agglutination - clumping together of pathogens, phagocyotsis of clumped pathogens
Neutralisation - Antibody blocks receptor site on pathogen. Bind to toxin hence prevents entry to host cell
State the humoral response
Activated t helper cells bind to b cells. B cells is activated by release of interleukins from t helper cells. B cells rapidly divide to make clones which differentiate into B memory cells and plasma cell from clonal expansion. Plasma cells can produce antibodies
What is automminue disease and state examples
Your own immune system identifies own body cells as foreign and thus results in WBC attacking your own body cells
1. Rheumatoid Arthirits
What is passive + active + natural + artificial immunity
PASSIVE - antibodies introduced into the body and pathogen does not enter body and plasma and memory cells are not made
(e.g - antibodies passed through foetus to placenta)
ACTIVE - involves exposure to pathogens (NATURAL -> immune system makes antibodies. PASSIVE -> Dead/weakened version of pathogen)
Define parasite
Lives on host, feeds on host at the expense of the host
What is the structure of antibodies
Contains variable region -> allows attachment of antigens
4 PP CHAINS
2 variable regions -> allows attachment for more than one antigen
constant region -> allows recognition by binding phagocytes
variable region on different antibodies allows specificity for different antigens
What is the role of opsonins
Binds to antigen on pathogen and then binds to phagocyte
How is mosquito parasite able to bypass primary defences
Mosquito mouthparts pierce skin - Pathogen release directly into the blood
Why are toxins produced by different strains decribed as “immunologically different”
Different strains produce different toxins
Each toxin will have a different a.a sequence
Toxin is an antigen and immune response is determined by the shape of antigen. Different compounds have different shapes
Why are vaccinations an example of active immunity
Immune system produces own antibodies
Memory cells remain
Activation of lymphocytes
