PHGY 216 FINAL EXAM 360 QUESTIONS AND CORRECT
ANSWERS UPDATED 2026 VERIFIED ANSWERS ACTUAL
UPDATED PRACTICE QUESTIONS HIGH YIELD STUDY
GUIDE HUMAN CHEMISTRY EXAM PREPARATION GRADED
A+
Water Balance - CORRECT ANSWER -- Every cell in the body requires a
well-regulated environment in order to survive and function
- Body water plays a large role in creating this environment, which is comprised
of intracellular and extracellular fluid
- When we talk about the major body compartments for water (fluid) there are
three key pools: ICF, plasma, and interstitial fluid, which remain distinct due to
the presence of "barriers" between them
Intracellular Fluid (ICF) - CORRECT ANSWER -This is the fluid within
the cells and comprises about two thirds of total body fluid
Extracellular Fluid (ECF) - CORRECT ANSWER -- This is the fluid
surrounding the cells which includes the plasma, the interstitial fluid, lymph,
and transcellular fluid (such as cerebrospinal fluid) and comprises about one
third of total body fluid
- The plasma is about one fifth of the ECF, the interstitial fluid is about four
fifths of the ECF, and the lymph and the transcellular fluid are considered
negligible
Transcellular Fluid - CORRECT ANSWER -The portion of total body
water contained within epithelial lined spaces
Barriers Between Body-Fluid Compartments - CORRECT ANSWER --
Several barriers separate the body-fluid compartments
,- This limits the movement of water and solutes between the various
compartments to differing degrees
Barriers Between the Plasma and Interstitial Fluid - CORRECT ANSWER -
- The plasma and the interstitial fluid are separated by the blood vessel walls
- At the level of the capillaries, water and everything else in the plasma (except
proteins) can freely exchange with the interstitial fluid
- Because of this, the composition of the plasma and the interstitial fluid are
essentially identical, except for the plasma protein
- Consequently, any change in one of these compartments is quickly reflected in
the other compartments
Barriers Between the Intracellular Fluid and the ECF - CORRECT
ANSWER -- This barrier is the plasma membrane that surrounds each cell in
the body
- The ICF contains proteins that do not exchange with the ECF
- There is an unequal distribution of ions across this barrier because the barrier
does not allow the passive movement of either ICF or ECF constituents across
the plasma membrane, preventing them from equilibrating through diffusion
ECF Volume and Osmolarity - CORRECT ANSWER -- All exchanges of
water and other constituents between the ICF and the external world are
dependent upon the ECF
- Even though cells tightly regulate their own ICF, it can be said that overall
control of fluid balance is dependent upon regulating the ECF
- In order to maintain fluid balance in the body the ECF volume and osmolarity
are regulated
ECF Volume - CORRECT ANSWER -- This is closely regulated to
maintain blood pressure
,- The maintenance of salt balance is important in the long-term regulation of
ECF volume
ECF Osmolarity - CORRECT ANSWER -- This is closely regulated to
prevent the swelling or shrinkage of cells
Control of ECF Volume - CORRECT ANSWER -- ECF volume directly
influences blood pressure by changing plasma volume
- Increasing ECF volume will increase plasma volume ,and thus increase arterial
blood pressure
- Consequently there are mechanisms in place to adjust blood pressure until the
ECF volume is returned to normal values
- There are short term control factor including the baroreceptor reflex and fluid
shifts
- There are long term control factors including fluid input and output
The Baroreceptor Reflex - CORRECT ANSWER -- Baroreceptors are
mechanoreceptor that are located in the carotid artery and the aortic arch (areas
within major arteries of the body), and they detect changes in arterial blood
pressure
- Through the effects of the autonomic nervous system on the heart and blood
vessels, teh baroreceptor reflex regulates blood pressure
- When pressure falls too low, cardiac output and total peripheral resistance will
increase to raise blood pressure
- When blood pressure rises above normal, both decrease to reduce blood
pressure
Total Peripheral Resistance - CORRECT ANSWER -- The resistance to
blood flow due to the constriction of blood vessels
- Higher total peripheral resistance leads to increased blood pressure
, Cardiac Output - CORRECT ANSWER -The amount of blood pumped by
the heart per minute
Fluid Shifts - CORRECT ANSWER -- A decrease in plasma volume can
temporarily be compensated for by a shift of the fluids out of the interstitial
compartments to the plasma
- The opposite is also true, an increase in plasma volume can cause fluid to shift
to the interstitial compartment
Fluid Input/Output - CORRECT ANSWER -- The short term control
mechanisms are only temporary and can only compensate for fairly minor
changes in ECF fluid volumes
- Long-term regulation of blood pressure is a primary function of the kidneys
and the thirst mechanism, controlling fluid output and input, respectively
- Control of urine output by the kidneys is critical for long-term regulation of
blood pressure
Control of Salt - CORRECT ANSWER -- Sodium, and the anions that are
associated with it (mainly chloride), account for more than 90% of the ECF's
solutes
- Whenever salt is transported across a membrane, water follows due to osmosis
- Therefore, by controlling salt levels, ECF volume is being controlled
- To maintain salt balance, salt input must equal salt output
Salt Input - CORRECT ANSWER -- Regulation of salt input is poor as it is
dependent upon dietary salt
- It is necessary on a daily basis to replace the salt lost in the feces and sweat,
which is about 0.5g/day for normal activity levels (higher activity levels will
increase the amount lost in sweat)
- The average input for Canadians is around 3.5 g/day
ANSWERS UPDATED 2026 VERIFIED ANSWERS ACTUAL
UPDATED PRACTICE QUESTIONS HIGH YIELD STUDY
GUIDE HUMAN CHEMISTRY EXAM PREPARATION GRADED
A+
Water Balance - CORRECT ANSWER -- Every cell in the body requires a
well-regulated environment in order to survive and function
- Body water plays a large role in creating this environment, which is comprised
of intracellular and extracellular fluid
- When we talk about the major body compartments for water (fluid) there are
three key pools: ICF, plasma, and interstitial fluid, which remain distinct due to
the presence of "barriers" between them
Intracellular Fluid (ICF) - CORRECT ANSWER -This is the fluid within
the cells and comprises about two thirds of total body fluid
Extracellular Fluid (ECF) - CORRECT ANSWER -- This is the fluid
surrounding the cells which includes the plasma, the interstitial fluid, lymph,
and transcellular fluid (such as cerebrospinal fluid) and comprises about one
third of total body fluid
- The plasma is about one fifth of the ECF, the interstitial fluid is about four
fifths of the ECF, and the lymph and the transcellular fluid are considered
negligible
Transcellular Fluid - CORRECT ANSWER -The portion of total body
water contained within epithelial lined spaces
Barriers Between Body-Fluid Compartments - CORRECT ANSWER --
Several barriers separate the body-fluid compartments
,- This limits the movement of water and solutes between the various
compartments to differing degrees
Barriers Between the Plasma and Interstitial Fluid - CORRECT ANSWER -
- The plasma and the interstitial fluid are separated by the blood vessel walls
- At the level of the capillaries, water and everything else in the plasma (except
proteins) can freely exchange with the interstitial fluid
- Because of this, the composition of the plasma and the interstitial fluid are
essentially identical, except for the plasma protein
- Consequently, any change in one of these compartments is quickly reflected in
the other compartments
Barriers Between the Intracellular Fluid and the ECF - CORRECT
ANSWER -- This barrier is the plasma membrane that surrounds each cell in
the body
- The ICF contains proteins that do not exchange with the ECF
- There is an unequal distribution of ions across this barrier because the barrier
does not allow the passive movement of either ICF or ECF constituents across
the plasma membrane, preventing them from equilibrating through diffusion
ECF Volume and Osmolarity - CORRECT ANSWER -- All exchanges of
water and other constituents between the ICF and the external world are
dependent upon the ECF
- Even though cells tightly regulate their own ICF, it can be said that overall
control of fluid balance is dependent upon regulating the ECF
- In order to maintain fluid balance in the body the ECF volume and osmolarity
are regulated
ECF Volume - CORRECT ANSWER -- This is closely regulated to
maintain blood pressure
,- The maintenance of salt balance is important in the long-term regulation of
ECF volume
ECF Osmolarity - CORRECT ANSWER -- This is closely regulated to
prevent the swelling or shrinkage of cells
Control of ECF Volume - CORRECT ANSWER -- ECF volume directly
influences blood pressure by changing plasma volume
- Increasing ECF volume will increase plasma volume ,and thus increase arterial
blood pressure
- Consequently there are mechanisms in place to adjust blood pressure until the
ECF volume is returned to normal values
- There are short term control factor including the baroreceptor reflex and fluid
shifts
- There are long term control factors including fluid input and output
The Baroreceptor Reflex - CORRECT ANSWER -- Baroreceptors are
mechanoreceptor that are located in the carotid artery and the aortic arch (areas
within major arteries of the body), and they detect changes in arterial blood
pressure
- Through the effects of the autonomic nervous system on the heart and blood
vessels, teh baroreceptor reflex regulates blood pressure
- When pressure falls too low, cardiac output and total peripheral resistance will
increase to raise blood pressure
- When blood pressure rises above normal, both decrease to reduce blood
pressure
Total Peripheral Resistance - CORRECT ANSWER -- The resistance to
blood flow due to the constriction of blood vessels
- Higher total peripheral resistance leads to increased blood pressure
, Cardiac Output - CORRECT ANSWER -The amount of blood pumped by
the heart per minute
Fluid Shifts - CORRECT ANSWER -- A decrease in plasma volume can
temporarily be compensated for by a shift of the fluids out of the interstitial
compartments to the plasma
- The opposite is also true, an increase in plasma volume can cause fluid to shift
to the interstitial compartment
Fluid Input/Output - CORRECT ANSWER -- The short term control
mechanisms are only temporary and can only compensate for fairly minor
changes in ECF fluid volumes
- Long-term regulation of blood pressure is a primary function of the kidneys
and the thirst mechanism, controlling fluid output and input, respectively
- Control of urine output by the kidneys is critical for long-term regulation of
blood pressure
Control of Salt - CORRECT ANSWER -- Sodium, and the anions that are
associated with it (mainly chloride), account for more than 90% of the ECF's
solutes
- Whenever salt is transported across a membrane, water follows due to osmosis
- Therefore, by controlling salt levels, ECF volume is being controlled
- To maintain salt balance, salt input must equal salt output
Salt Input - CORRECT ANSWER -- Regulation of salt input is poor as it is
dependent upon dietary salt
- It is necessary on a daily basis to replace the salt lost in the feces and sweat,
which is about 0.5g/day for normal activity levels (higher activity levels will
increase the amount lost in sweat)
- The average input for Canadians is around 3.5 g/day
