chapter 6- foreign invders- self vs non self

disease

any condition that affects normal function of either a part of an organism or complete organims

noninfectious (non communicable diseases)

cannot be transmitted from one organism to another. result from poor lifestyle choices

infectious (communicable disease)

can be transmittted from one organism to another. result from pathogens

pathogen

disease causing agent or organism

contact transmission

direct e.g handshake or indirect via smth inbetween e.g toothbrushes

medium transmission

air,food,water borne

vector

a living organism that carries and transmits a pathogen from one organism to another e.g mosiquoito, flea

course of disease

1. Incubation

2. symptoms of disease

3. recovery

incubation

pathogen may take time to multiply to a number sufficent to cause diease, reach target tissue

symptoms of disease

result from bodys immune system trying to eliminate infection or they are the effect the pathogen has on the body of host

recovery

hosts immune system will fight off pathogen

antigens

a unique marker on the surface of cells or viruses that is used in identifiying self from non slef

self antigens

unique, specific self markers (antigens) on the surface of your cell that your immune cells recongise and respond to (mark it as self cell)

non self antigens

originate outside the body, antigen on surface of cells that is identifyied by immune system as foreign and triggers immune response when detected

mhc markers stands for

major histocompatibility complex

what are mhc 1 markers

these are proteins on the surface of all nucleated cells in the body (not red blood) their role is to identify is the cell is self or non self

mhc class 1

a type of protein marker on the surface of all nucleated cells that assists in the identification of self from non slef

mhc class 2

a type of protein marker on antigen presenting white blood cells that is used in the activation of a specifc immune response

antigen presenting cell

a specific type of white blood cell that uses phagocytosis to engulf a pathogen before displaying peptide fragments (epitodes) on its MHC class 2 markers for detection by white blood cells

what is an allergic reaction

an overreaction by the body's immune system to a normally harmless substance

cellular pathogens

living organism that causes disease within a host

bacteria (prok, unicell)

most baceteria are non-pathegenic, some are because they produce endotoxins- only toxic when they die or exotoxin

endotoxins

toxins part of cell wall of gram negative bacteria- lipid coat on outside of cell wall

exotoxin

toxic chemicals released by bacteria into their environment

superbugs

overuse of antibiotics have lef to many bacteria developing resistance

fungi (can be uni or multi)

reproduce by speading microspoic spores

superficial- affect external surfaces

multicell pathogesn

some are multicell euk like tapeworms

non cellular pathogens

disease causing agent that lacks cellular structures and cannot replicate outside host cell

viruses

composed of nucleic acid enclosed within a capsid (protein coat/shell) made of protein

how to viruses reproduce

inserting their nucleic acid into host cell

viral attachment and entry into host

1. attachment
2. entry
3. replication
4. assembly
5. release

bacteriophages

a virus that specifically infects bacteria

types of pathogens

prions and virods

what are prions

infectious proteins, misfolded proteins able to pass their shape on to normal variants of the same protein

virods

infectious, short, single stranded molecules of rna, cause diesease in plants

things about prions

no genome, transmissable, both infectious and hereditary

catergories of disease

infectious, pollution, social, genetic, defiency, degenerative

intracellular

within cell

intercellular

between cells

epidemic

rapid spread of an infectious disease to a large number of people within a population

pandemic

outbreak of infectious disease, occurs over a wide geographical area affecting large number

malfunctions involving antigens

autoimmune disease and allergies that occur when the immune system mistakenly attacks the body or reacts excessively to benign substances.