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BIO 325 MESSERLI FINAL EXAM (LATEST EXAM 2026
) MOST RECENT EXAM ACTUAL COMPLETE REAL
VERIFIED EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) ALREADY GRADED
A+ | GUARANTEED SUCCESS!! NEWEST EXAM!!!
Come up with an example of a physiological response that
is homeostatic but not negative feedback - Answer-platelet
activation
How does Sammy's cellular respiration change as he
nears the end of a long race and sprints for the finish line?
- Answer-changes: endurance to power, aerobic
respiration to anaerobic respiration, glucose is burned,
little oxygen use, produces lactic acid, nonefficient long
term
maximizes both aerobic and anaerobic
Carli stands up. Outline the reflex that will adjust her blood
pressure in response. - Answer-stimulus: low blood
pressure
sensor: receptor cell (baroreceptor)
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afferent pathway: sensory nerve
integrating center: medulla oblongata
efferent pathway: increase Sym, or angiotensin, cortisol,
epinephrine, or ADH, or reduced Psym
effector: muscle or gland responsible (heart or blood
vessels)
response: increase rate and strength or constrict
Ten glucose molecules enter Javier's kidneys. He's
healthy and eating normally. Describe the paths these
molecules may take until they leave the kidneys. - Answer-
1. afferent arteriole
2. glomerular capillaries/Bowman's capsule
3. proximal convoluted tubule
4. peritubular capillaries
5. into the bloodstream
other path is no filtration
How would paths differ if the molecules were protons and
the individual had a dangerously low blood pH? - Answer-
1. afferent arteriole2. efferent arteriole3. peritubular
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capillaries4. distal convoluted tubule5. collecting ducts6.
renal pelvis
not filtered and not reabsorbed but secreted
David is running. How does this change oxygen
concentrations in his lungs, and in his legs? How does it
affect oxygen pickup and delivery? If oxygen
concentrations change by 10% in each of these places,
will any changes in oxygen pickup and delivery be greater,
about, or less than 10%? - Answer-- Exercise will cause
low oxygen in the leg muscles, and a smaller decrease in
oxygen concentration in the lungs.
- Oxygen pickup in the lungs is decreased by less than
10% (-2% change would be a good estimate) while
oxygen delivery in the active muscles increases by more
than 10%; perhaps 50%.
- This comes from the hemoglobin saturation curve, using
a value of about 90 mm Hg for lung oxygen concentrations
in the lungs during a run (bringing saturation to about 96%
from its normal 98% in the pulmonary caps) and a value of
about 36 mm Hg for oxygen concentration in the active
tissues (bringing saturation to roughly 65%, which means
some Hb have dropped off 2 instead of the normal 1
oxygen molecules)
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What key questions must be answered to discover if a
variable is homeostatic? - Answer-Homeostatic variables
have systems that defend their levels near the setpoint, so
the homeostatic variables don't change much despite
disturbances to the system.
What key questions must be answered to discover if a
variable is allostatic? - Answer-Allostatic variables change
much more; they are the variables that are intentionally
changed in order to maintain the level of some
homeostatic variable.
How to know if its a negative feedback system? - Answer-
Negative feedback systems have to have responses that
reduce the stimulus that triggered the response
What path did those oxygen molecules take from David's
nose into their final sites of use? - Answer-nasal passages
--> pharynx --> larynx --> trachea --> bronchi -->
bronchioles --> alveoli --> blood --> body
Which respiratory parameters will change if David, a
previously sedentary man, picks up the habit of running
several times a week? - Answer-none
BIO 325 MESSERLI FINAL EXAM (LATEST EXAM 2026
) MOST RECENT EXAM ACTUAL COMPLETE REAL
VERIFIED EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) ALREADY GRADED
A+ | GUARANTEED SUCCESS!! NEWEST EXAM!!!
Come up with an example of a physiological response that
is homeostatic but not negative feedback - Answer-platelet
activation
How does Sammy's cellular respiration change as he
nears the end of a long race and sprints for the finish line?
- Answer-changes: endurance to power, aerobic
respiration to anaerobic respiration, glucose is burned,
little oxygen use, produces lactic acid, nonefficient long
term
maximizes both aerobic and anaerobic
Carli stands up. Outline the reflex that will adjust her blood
pressure in response. - Answer-stimulus: low blood
pressure
sensor: receptor cell (baroreceptor)
,2|Page
afferent pathway: sensory nerve
integrating center: medulla oblongata
efferent pathway: increase Sym, or angiotensin, cortisol,
epinephrine, or ADH, or reduced Psym
effector: muscle or gland responsible (heart or blood
vessels)
response: increase rate and strength or constrict
Ten glucose molecules enter Javier's kidneys. He's
healthy and eating normally. Describe the paths these
molecules may take until they leave the kidneys. - Answer-
1. afferent arteriole
2. glomerular capillaries/Bowman's capsule
3. proximal convoluted tubule
4. peritubular capillaries
5. into the bloodstream
other path is no filtration
How would paths differ if the molecules were protons and
the individual had a dangerously low blood pH? - Answer-
1. afferent arteriole2. efferent arteriole3. peritubular
,3|Page
capillaries4. distal convoluted tubule5. collecting ducts6.
renal pelvis
not filtered and not reabsorbed but secreted
David is running. How does this change oxygen
concentrations in his lungs, and in his legs? How does it
affect oxygen pickup and delivery? If oxygen
concentrations change by 10% in each of these places,
will any changes in oxygen pickup and delivery be greater,
about, or less than 10%? - Answer-- Exercise will cause
low oxygen in the leg muscles, and a smaller decrease in
oxygen concentration in the lungs.
- Oxygen pickup in the lungs is decreased by less than
10% (-2% change would be a good estimate) while
oxygen delivery in the active muscles increases by more
than 10%; perhaps 50%.
- This comes from the hemoglobin saturation curve, using
a value of about 90 mm Hg for lung oxygen concentrations
in the lungs during a run (bringing saturation to about 96%
from its normal 98% in the pulmonary caps) and a value of
about 36 mm Hg for oxygen concentration in the active
tissues (bringing saturation to roughly 65%, which means
some Hb have dropped off 2 instead of the normal 1
oxygen molecules)
, 4|Page
What key questions must be answered to discover if a
variable is homeostatic? - Answer-Homeostatic variables
have systems that defend their levels near the setpoint, so
the homeostatic variables don't change much despite
disturbances to the system.
What key questions must be answered to discover if a
variable is allostatic? - Answer-Allostatic variables change
much more; they are the variables that are intentionally
changed in order to maintain the level of some
homeostatic variable.
How to know if its a negative feedback system? - Answer-
Negative feedback systems have to have responses that
reduce the stimulus that triggered the response
What path did those oxygen molecules take from David's
nose into their final sites of use? - Answer-nasal passages
--> pharynx --> larynx --> trachea --> bronchi -->
bronchioles --> alveoli --> blood --> body
Which respiratory parameters will change if David, a
previously sedentary man, picks up the habit of running
several times a week? - Answer-none
