chap 6- responding to antigens Flashcards
what are microbes
small cellular organisms that can only be seen with a microscope
what is an example of a protist
bacteria
example of protozoans
malaria
example of fungi
yeast or athletes foot
example of a virus
covid-19
example of prions
mad cow disease
how can pathogens be transmitted
person-person contact
airborne droplets
contact with contaminated objects, food or blood
injection of contaminated food or water
vectors that carry pathogenic agents and spread them to people
what is the pathway for disease to occur
1- gain entry to the organism
2- reach target cells
3- overcome body’s defense systems
4- become established at one or more sites
5- multiply rapidly
6- cause harm to the host and produce the symptoms of disease
what does the first line of defence do
stops pathogens from causing damage
is the first line of defense innate and non specific
yes
what does innate mean
from birth
what does non-specific mean
works on any pathogen
what do physical barriers do
act to stop pathogenic material from gaining entry into the body
example of physical barriers in animals
intact skin, mucus- membranes, sneezing/coughing/vomiting
example of physical barriers in plants
thick bark, wax coatings, cellulose cell wall
what do chemical barriers in animals do
chemicals attack pathogenic material
examples of chemical barriers in animals
stomach acid (contains HCl)
sweat/tears/saliva (contains lysozyme
fluid in lungs (contains surfactants)
examples of chemical barriers in plants
caffeine (is toxic to insects and fungi)
tannins (toxic to insects)
citronella (repels insects)
what do microbiota barriers do
act to prevent colonization of microorganisms that may be pathogenic.
when do be acquire normal microbiota
from birth
is the second line of defense innate and non-specific
yes
when does the second line of defence kick in
after microbes pass 1st line of defence
where does second line of defense mainly occur
at sight of infection
what does second line of defence react against
microbes
what is inflammation
the accumulation of fluid, plasma proteins and leukocytes that occurs when tissue is damaged/infected
what is inflammation characterized by
pain, redness, heat and swelling
what triggers the inflammatory response
the interaction between leukocytes and pathogens triggers the inflammatory response that results from the production, activation or release of substances such as complement proteins and cytokines.
what are leukocytes
all cells in the immune system are WBC (leukocytes). derived from pluripotent stem cells in bone marrow
what are phagocytes
WBC that engulfs foreign matter (endocytosis). they arrive at sight of infection first
what are the phagocytes
macrophages, neutrophils and dendritic cells