Ivy Tech APHY 201 Exam question with
answers
External body surfaces are... - -continuous with the external environment
-What are the 6 external body surfaces? - -1) Nasal and oral passages
2) Respiratory tract
3) GI tract
4) Urinary tract
5) Reproductive tract
6) Ducts of exocrine glands
-Internal body surfaces can only be accessed... - -from an internal body fluid
or
by transport across an external membrane
-What are the 3 internal body surfaces? - -1) Cell membranes of cells within the
body
2) Cardiovascular and lymphatic membranes
3) Serous and connective tissue membranes
-Membranes divide the body into compartments that... - -maintain separate
chemical environments
-What is the external face of the membrane? - -the surface facing the environment
outside of the body
-What is the apical (or huminal) face of the membrane? - -the surface facing the
lumen of a hallow structure
-What is the basolateral face of the membrane? - -the surface facing the intestinal
environment
-What are the 7 fluid compartments of the body? - -1) Blood plasma and lymph
2) Interstitial fluid
3) Intracellular fluid
4) Fluid in membranous organelles
5) Cerebrospinal fluid
6) Synovial cavities
7) Chambers in eyeballs and ears
-Intracellular fluid contains how much of the body's water? - -2/3 (28L)
-Extracellular fluid contains how much of the body's water? - -1/3 (14L)
(3L blood plasma, 11L interstitial fluid)
-Filtration - -Pressure driven (blood pressure and fluid hydrostatic pressure)
, -Diffusion - -Driven by concentration gradients
-Osmosis - -Driven by concentration gradients of solutes (only water)
-Routes of water loss - -1) Evaporation from skin and moist membranes, sweat (+/-
900mL)
2) Feces (+/- 100mL)
3) Urine (+/- 1.5L)
-Routes of water gains - -1) Food, beverages (+/- 2.25L)
2) Metabolism (+/- 250mL)
-Primary receptors of the thirst mechanism - -Hypothalamic receptor neurons signal
the thirst center when blood plasma osmolarity > 280 mOsm
-Secondary receptors of the thirst mechanism - -Osmoreceptors in the mouth
detect low volume and increase concentration of saliva
-Integrating center - -Hypothalamic thirst center
-Stimulation of the thirst center causes... - -1) Stimulation of water-seeking
behaviors through the cerebral cortex
2) Increased water conservation by the kidneys, through ADH from the posterior
pituitary
-Temporary cessation of thirst - -Moistening of oral osmoreceptors (inhibits
hypothalamic thirst center only as long as the mouth remains moist)
-Long term cessation of thirst - -Return to normal plasma osmolarity (strongly
inhibits thirst center; as long as plasma osmolarity remains normal, thirst is fully
inhibited)
-Renal response - -Cannot fix dehydration; only reduces water loss
(reduces filtrate formation and increases water absorption from the urine)
-Hypothalamic compensations for overhydration - -Plasma osmolarity < 280 mOsm
strongly inhibits thirst by quieting receptor neurons
-Renal Response compensations for overhydration - -Increase water loss in urine by
increasing filtrate formation and inhibiting water absorption from the urine
-Homeostasis - -The ability of the body to maintain optimal performance of a
system under a given set of conditions
-When conditions of homeostasis change... - -homeostatic set points change to
maintain the optimal performance of the system
-Feedback loops - -Systems that allow communication between cells to maintain a
physiological system within a given range of function
answers
External body surfaces are... - -continuous with the external environment
-What are the 6 external body surfaces? - -1) Nasal and oral passages
2) Respiratory tract
3) GI tract
4) Urinary tract
5) Reproductive tract
6) Ducts of exocrine glands
-Internal body surfaces can only be accessed... - -from an internal body fluid
or
by transport across an external membrane
-What are the 3 internal body surfaces? - -1) Cell membranes of cells within the
body
2) Cardiovascular and lymphatic membranes
3) Serous and connective tissue membranes
-Membranes divide the body into compartments that... - -maintain separate
chemical environments
-What is the external face of the membrane? - -the surface facing the environment
outside of the body
-What is the apical (or huminal) face of the membrane? - -the surface facing the
lumen of a hallow structure
-What is the basolateral face of the membrane? - -the surface facing the intestinal
environment
-What are the 7 fluid compartments of the body? - -1) Blood plasma and lymph
2) Interstitial fluid
3) Intracellular fluid
4) Fluid in membranous organelles
5) Cerebrospinal fluid
6) Synovial cavities
7) Chambers in eyeballs and ears
-Intracellular fluid contains how much of the body's water? - -2/3 (28L)
-Extracellular fluid contains how much of the body's water? - -1/3 (14L)
(3L blood plasma, 11L interstitial fluid)
-Filtration - -Pressure driven (blood pressure and fluid hydrostatic pressure)
, -Diffusion - -Driven by concentration gradients
-Osmosis - -Driven by concentration gradients of solutes (only water)
-Routes of water loss - -1) Evaporation from skin and moist membranes, sweat (+/-
900mL)
2) Feces (+/- 100mL)
3) Urine (+/- 1.5L)
-Routes of water gains - -1) Food, beverages (+/- 2.25L)
2) Metabolism (+/- 250mL)
-Primary receptors of the thirst mechanism - -Hypothalamic receptor neurons signal
the thirst center when blood plasma osmolarity > 280 mOsm
-Secondary receptors of the thirst mechanism - -Osmoreceptors in the mouth
detect low volume and increase concentration of saliva
-Integrating center - -Hypothalamic thirst center
-Stimulation of the thirst center causes... - -1) Stimulation of water-seeking
behaviors through the cerebral cortex
2) Increased water conservation by the kidneys, through ADH from the posterior
pituitary
-Temporary cessation of thirst - -Moistening of oral osmoreceptors (inhibits
hypothalamic thirst center only as long as the mouth remains moist)
-Long term cessation of thirst - -Return to normal plasma osmolarity (strongly
inhibits thirst center; as long as plasma osmolarity remains normal, thirst is fully
inhibited)
-Renal response - -Cannot fix dehydration; only reduces water loss
(reduces filtrate formation and increases water absorption from the urine)
-Hypothalamic compensations for overhydration - -Plasma osmolarity < 280 mOsm
strongly inhibits thirst by quieting receptor neurons
-Renal Response compensations for overhydration - -Increase water loss in urine by
increasing filtrate formation and inhibiting water absorption from the urine
-Homeostasis - -The ability of the body to maintain optimal performance of a
system under a given set of conditions
-When conditions of homeostasis change... - -homeostatic set points change to
maintain the optimal performance of the system
-Feedback loops - -Systems that allow communication between cells to maintain a
physiological system within a given range of function
