QUESTIONS WITH VERIFIED ANSWERS
{ GRADED A+}
what is a non-specific (innante) defense? - ✔✔they're effective against
a wide variety of invading microbes; not targeted against a specific
invading microbe
why are non-specific defenses referred to as innate? - ✔✔they are
already present in a baby at birth rather than being acquired one-by-
one over a lifetime starting at birth
what are non-specific first line defenses? - ✔✔physical barriers,
chemical barriers, and microbiota barriers
,how is skin a physical barrier? - ✔✔it protects against microbial
invasion; it's built of tightly packed cells, the outer layer consists of
dead cells and keratin, skin is dry and cells are shed continuously
how are mucous membranes a physical barrier? - ✔✔they protects
against microbial invasion because they are built of tightly packed
epithelial cells, they secrete thick, sticky mucus which covers the
surface of the membrane, and mucous can trap microbes
are mucus membranes as effective as skin? - ✔✔no because they lack
keratin
what do mucous membranes line? - ✔✔respiratory, gastrointestinal,
and genitourinary tracks helping systems from microbial invasion
what is the ciliary escalator? - ✔✔it's a special mucous membrane
lining the airways of the respiratory tract. the cilia sweep the microbes
upward, away from the lungs to the throat where they can be
swallowed
, how are bodily fluids a physical barrier? - ✔✔tissues are washed or
flushed by the movement of certain body fluids like tears, saliva, and
urine
how is microbiota a barrier? - ✔✔normal microbiome protects against
invasion of potential pathogens
what are the 3 different chemical barriers? - ✔✔lysozyme, acid, and
bile
how is lysozyme a chemical barrier? - ✔✔it is found in mucous
secretions; tears, sweat, and saliva. it kills certain bacteria by destroying
their cell walls
how is acid/low pH a chemical barrier? - ✔✔it kills microbes in the
stomach, vagina, bladder, and on skin
how is bile a chemical barrier? - ✔✔it's a digestive molecule that kills
microbes in the small intestine