Microbio 4000: Exam 4 Test Questions
with All Correct Answers 2026-2027
Updated.
immunity - Answer ability to ward off disease cause by microbes and their products and
protect against environmental agents
susceptibility - Answer lack of immunity
pattern recognition receptors (PRRs) - Answer recognize elements frequently found of
microbes but different from the host
toll like receptors (TLRs) - Answer one class of PRRs on host that recognize PAMPs
cytokines - Answer proteins that regulate the intensity and duration of immune responses
two types of immunity - Answer innate and adaptive
innate immunity - Answer more general, defenses from birth, provides rapid response,
doesn't recognize specific microbes, no memory response, 1st and 2nd lines of defense
adaptive immunity - Answer acquired, slower to respond, specific responses to microbes,
memory component, 3rd line of defense
basics of innate immunity - Answer 1. activated by protein receptors in the plasma
membrane of defensive cells
2. TLRs attached to components commonly found on pathogens called PAMPs
3. TLRs bound to PAMPs induce the release of cytokines from the host cell
epidermis - Answer out, thinner portion of skin
keratin - Answer protective protein
dermis - Answer inner, thicker portion of skin, made of connective tissue
, mucus membrane - Answer epithelial layer and underlying connective tissue that line the GI,
respiratory, and GO tracts
normal microbiota - Answer microorganisms that establish a residence but don't produce
disease under normal conditions
prebiotics - Answer chemicals that selectively promote the growth of beneficial bacteria
probiotics - Answer live microbial cultures administered to exert a beneficial effect
first line defenses - Answer physical barriers, chemical factors, normal microbiota
purpose of physical barriers - Answer block entry of microbes, largest are skin and mucus
membranes
physical barriers: skin - Answer - largest organ
- epidermis is in direct contact with outside environment, dead, contains keratin, tightly packed
- dermis
how does the skin act as a physical barrier? - Answer prevents entry via arrangement and
structure, shedding of dead cells, tightly packed
physical barrier: mucus membrane - Answer secrete mucus (glycoprotein) that prevents
tracts from drying out and helps trap microbes
physical barrier: ciliary escalator - Answer transports microbes trapped in mucus away from
lungs
physical barrier: lacrimal appartus - Answer drains tears, washes eyes
physical barrier: saliva - Answer dilutes and washes teeth
physical barrier: earwax - Answer prevents microbes from entering ear
physical barrier: urine - Answer cleans out urethra via flow
physical barrier: vaginal secretions - Answer move microbes out of vaginal tract
with All Correct Answers 2026-2027
Updated.
immunity - Answer ability to ward off disease cause by microbes and their products and
protect against environmental agents
susceptibility - Answer lack of immunity
pattern recognition receptors (PRRs) - Answer recognize elements frequently found of
microbes but different from the host
toll like receptors (TLRs) - Answer one class of PRRs on host that recognize PAMPs
cytokines - Answer proteins that regulate the intensity and duration of immune responses
two types of immunity - Answer innate and adaptive
innate immunity - Answer more general, defenses from birth, provides rapid response,
doesn't recognize specific microbes, no memory response, 1st and 2nd lines of defense
adaptive immunity - Answer acquired, slower to respond, specific responses to microbes,
memory component, 3rd line of defense
basics of innate immunity - Answer 1. activated by protein receptors in the plasma
membrane of defensive cells
2. TLRs attached to components commonly found on pathogens called PAMPs
3. TLRs bound to PAMPs induce the release of cytokines from the host cell
epidermis - Answer out, thinner portion of skin
keratin - Answer protective protein
dermis - Answer inner, thicker portion of skin, made of connective tissue
, mucus membrane - Answer epithelial layer and underlying connective tissue that line the GI,
respiratory, and GO tracts
normal microbiota - Answer microorganisms that establish a residence but don't produce
disease under normal conditions
prebiotics - Answer chemicals that selectively promote the growth of beneficial bacteria
probiotics - Answer live microbial cultures administered to exert a beneficial effect
first line defenses - Answer physical barriers, chemical factors, normal microbiota
purpose of physical barriers - Answer block entry of microbes, largest are skin and mucus
membranes
physical barriers: skin - Answer - largest organ
- epidermis is in direct contact with outside environment, dead, contains keratin, tightly packed
- dermis
how does the skin act as a physical barrier? - Answer prevents entry via arrangement and
structure, shedding of dead cells, tightly packed
physical barrier: mucus membrane - Answer secrete mucus (glycoprotein) that prevents
tracts from drying out and helps trap microbes
physical barrier: ciliary escalator - Answer transports microbes trapped in mucus away from
lungs
physical barrier: lacrimal appartus - Answer drains tears, washes eyes
physical barrier: saliva - Answer dilutes and washes teeth
physical barrier: earwax - Answer prevents microbes from entering ear
physical barrier: urine - Answer cleans out urethra via flow
physical barrier: vaginal secretions - Answer move microbes out of vaginal tract
