PHS3341 Final Exam (Physiology 1) Questions With
Complete Solutions
a- On the inside, positive charges flow through the ICF 1.
(AWAY or TOWARDS) from the relatively more positive
depolarized active region 2.(AWAY or TOWARDS) the more
negative adjacent resting regions.
b- Outside the cell, positive charges flow through the ECF from
the more
3.(POSITIVE or NEGATIVE) adjacent inactive regions 4.
(AWAY or TOWARDS) the relatively more negative active
region.
1. AWAY
2. TOWARD
3. POSITIVE
4. TOWARD
Do action potentials diminish in strength as they continue to
propagate?
T or F?
FALSE; They can travel long distances, unlike graded-
potentials. They span throughout the entire cell membrane,
rather than just a certain area.
What is "flux"?
Refers to the amount of substance diffusing across a surface in a
unit of time.
What is "net flux"?
,A difference between 2 compartments (ex. Inside and outside of
the cell) at any instant is the difference between the 2 one-way
fluxes.
ALWAYS processes from higher concentration to a lower
concentration.
Do non-polar hydrophobic molecules easily diffuse through
the phospholipid bilayer?
YES;
= The membrane is selectively permeable with a hydrophobic
core.
=Allows simple diffusion of hydrophobic molecules (ex. oxygen,
carbon dioxide, steroid hormones, fatty acids).
List the synaptic inputs:
1. Axo-axonic
2. Axo-somatic
3. Axo-dendritic
Regulated (sensed) variable:
-Has a sensor and is kept within a limited range by
physiological mechanisms.
-Some of these variables are stable over time, but are NOT
homeostatic (ex. blood hematocrit or testosterone levels)
depending on the system.
Non-regulated (controlled) variable:
-Variables that can be changed by the body, but has no sensors.
, -Modulated to achieve regulation of the variable being held
constant (ex. heart rate; can be changed by ANS to regulate BP,
but there are no sensors in the system to measure HR directly).
Initiates a change in the variable being regulated to bring about
responses that tend to push the variable in the opposite direction
of the original change - back to normal range (set point/
stability) & minimizes changes.
This refers to what kind of feedback loop?
a) Positive Feedback Loop
b) Negative Feedback Loop
c) Feed Forward Feedback Loop
b) Negative Feedback Loop
Which parts make up the homeostatic control system?
=Set point, sensor, error detector, integrator, effectors.
Accelerates a process (less common because it pushes values
away from the set point by increasing one (or more) variables.
Without this process, the body will be unable to have success
with this change (Stimulus is required to push past set point).
This refers to what kind of feedback loop?
a) Positive Feedback Loop
b) Negative Feedback Loop
c) Feed Forward Feedback Loop
a) Positive Feedback Loop
Homeostatic control systems cannot maintain 1._____________
of any given feature of the internal environment. Any regulated
Complete Solutions
a- On the inside, positive charges flow through the ICF 1.
(AWAY or TOWARDS) from the relatively more positive
depolarized active region 2.(AWAY or TOWARDS) the more
negative adjacent resting regions.
b- Outside the cell, positive charges flow through the ECF from
the more
3.(POSITIVE or NEGATIVE) adjacent inactive regions 4.
(AWAY or TOWARDS) the relatively more negative active
region.
1. AWAY
2. TOWARD
3. POSITIVE
4. TOWARD
Do action potentials diminish in strength as they continue to
propagate?
T or F?
FALSE; They can travel long distances, unlike graded-
potentials. They span throughout the entire cell membrane,
rather than just a certain area.
What is "flux"?
Refers to the amount of substance diffusing across a surface in a
unit of time.
What is "net flux"?
,A difference between 2 compartments (ex. Inside and outside of
the cell) at any instant is the difference between the 2 one-way
fluxes.
ALWAYS processes from higher concentration to a lower
concentration.
Do non-polar hydrophobic molecules easily diffuse through
the phospholipid bilayer?
YES;
= The membrane is selectively permeable with a hydrophobic
core.
=Allows simple diffusion of hydrophobic molecules (ex. oxygen,
carbon dioxide, steroid hormones, fatty acids).
List the synaptic inputs:
1. Axo-axonic
2. Axo-somatic
3. Axo-dendritic
Regulated (sensed) variable:
-Has a sensor and is kept within a limited range by
physiological mechanisms.
-Some of these variables are stable over time, but are NOT
homeostatic (ex. blood hematocrit or testosterone levels)
depending on the system.
Non-regulated (controlled) variable:
-Variables that can be changed by the body, but has no sensors.
, -Modulated to achieve regulation of the variable being held
constant (ex. heart rate; can be changed by ANS to regulate BP,
but there are no sensors in the system to measure HR directly).
Initiates a change in the variable being regulated to bring about
responses that tend to push the variable in the opposite direction
of the original change - back to normal range (set point/
stability) & minimizes changes.
This refers to what kind of feedback loop?
a) Positive Feedback Loop
b) Negative Feedback Loop
c) Feed Forward Feedback Loop
b) Negative Feedback Loop
Which parts make up the homeostatic control system?
=Set point, sensor, error detector, integrator, effectors.
Accelerates a process (less common because it pushes values
away from the set point by increasing one (or more) variables.
Without this process, the body will be unable to have success
with this change (Stimulus is required to push past set point).
This refers to what kind of feedback loop?
a) Positive Feedback Loop
b) Negative Feedback Loop
c) Feed Forward Feedback Loop
a) Positive Feedback Loop
Homeostatic control systems cannot maintain 1._____________
of any given feature of the internal environment. Any regulated
