Ch 43 pt 1 Flashcards
(108 cards)
What are pathogens?
agents that cause disease
dedicated cells of the _________ interact with and destroy ________
Immune system, pathogens
Name the 4 cellular pathogens
1) parasites
2) protozoa
3) fungi
4) prokaryote
Name the 2 acellular pathogens
1) virus
2) prions
What are the 2 types of molecular recognition that allow detection of non-self molecules, particles, and cells?
1) Innate Immunity
2) Adaptive Immunity
What is innate immunity? (2)
1) recognition of traits SHARED by broad ranges of pathogens using a SMALL set of receptors
2) Rapid response
What is adaptive immunity? (2)
1) recognition of traits SPECIFIC to particular pathogens using a VAST array of receptors
2) Slower response
What are the 2 types of defenses in innate immunity?
1) Barrier defenses
2) Internal defenses
What are the 3 barrier defenses?
1) skin
2) mucous membrane
3) secretions
What are the 4 types of internal defenses
1) phagocytic cells
2) natural killer cells
3) antimicrobial proteins
4) inflammatory response
PAIN
What are the 2 types of adaptive immunity responses? (describe them)
1) humoral response: ANTIBODIES defend against infections in body FLUIDS
2) cell-mediated response: CYTOTOXIC CELLS defend against infections in body CELLS
What are the 3 parts of innate immunity in invertebrates?
1) An exoskeleton made of chitin forms 1st barrier
2) chitin based barrier + lysozyme protect digestive system
3) hemocytes in hemolymph carry out phagocytosis
What does lysozyme do?
Breaks down bacterial cell walls
What do hemocytes do?
Secret antimicrobial peptides that disrupt plasma membrane of fungi and bacteria
How does the immune system recognize bacteria and fungi?
Structures on their cell walls (antigens)
How do insects defend against viruses?
they can recognize virus double-stranded RNA
Explain antiviral defense in insects (3)
1) virus infects host cell and begins replicating ssRNA
2) Dicer-2 recognizes foreign dsRNA and cuts it up
3) Argo protein picks one up and now “knows” what to destroy by cleaving
What is the main goal of innate immunity in vertebrates?
recognize that something is foreign
What are the barrier defenses in innate immunity in vertebrates?
In respiratory, urinary, and reproductive tracts:
1) Skin
2) Mucous membrane
What allow for the removal of microbes?
mucus traps
What bodily fluids are hostile to microbes?
1) Saliva
2) Mucus
3) Tears
by lysozymes that break cell walls
What are the affects of low pH of the skin and digestive system?
prevents growth of bacteria
How do mammals detect invading pathogens?
use cells called Toll-like receptors (TLR’s)
How do TLR’s recognize pathogens?
they recognize fragments of molecules of a set of pathogens