t
ne
WGU D236 PATHOPHYSIOLOGY FINAL EXAM 180 QUESTIONS AND CORRECT DETAILED
sh
ANSWERS LATEST UPDATE 2023-2024
ne
la
tz
sh
Sp
ne
1. What is Starling's Law of Capillary forces? How does this explain why a
la
nutritionally deficient child would have edema?
Starling’s Law describes how fluids move across the capillary membrane. There are two
sh
Sp
major opposing forces that act to balance each other, hydrostatic pressure (pushing water out of
the capillaries) and osmotic pressure (including oncontic pressure, which pushes fluid into the
ne
capillaries). Both electrolytes and proteins (oncontic pressure) in the blood affect osmotic pressure,
high electrolyte and protein concentrations in the blood would cause water to leave the cells and
la
interstitial space and enter the blood stream to dilute the high concentrations. On, the other hand,
tz
low electrolyte and protein concentrations (as seen in a nutritionally deficient child) would cause
sh
Sp
water to leave the capillaries and enter the cells and interstitial fluid which can lead to edema.
ne
2. How does the RAAS (Renin-Angiotensin-Aldosterone System) result in
la
increased blood volume and increased blood pressure?
sh
Sp
A drop in blood pressure is sensed by the kidneys by low perfusion, which in turn begins to
secrete renin. Renin then triggers the liver to produce angiotensinogen, which is converted to
ne
Angiotensin I in the lungs and then angiotensin II by the enzyme Angiotensin-converting enzyme
(ACE). Angiotensin II stimulates peripheral arterial vasoconstriction which raises BP. Angiotensin II is
la
also stimulating the adrenal gland to release aldosterone, which acts to increase sodium and water
tz
reabsorption increasing blood volume, while also increased potassium secretion in urine.
sh
Sp
ne
3. How can hyperkalemia lead to cardiac arrest?
la
Normal levels of potassium are between 3.5 and 5.2 mEq/dL. Hyperkalemia refers to
sh
potassium levels higher that 5.2 mEq/dL. A major function of potassium is to conduct nerve impulses
Sp
in muscles. Too low and muscle weakness occurs and too much can cause muscle spasms. This is
especially dangerous in the heart muscle and an irregular heartbeat can cause a heart attack.
ne
la
4. The body uses the Protein Buffering System, Phosphate Buffering System, and
tz
Carbonic Acid-Bicarbonate System to regulate and maintain homeostatic pH,
sh
Sp
what is the consequence of a pH imbalance?
ne
Proteins contain many acidic and basic group that can be affected by pH changes. Any
la
increase or decrease in blood pH can alter the structure of the protein (denature), thereby
affecting its function as well.
sh
Sp
5. Describe the laboratory findings associated with metabolic
Want to earn $103 per month?
ne
la
acidosis, metabolic alkalosis, respiratory acidosis and respiratory alkalosis. (ie
tz
relative pH and CO2 levels).
sh
Sp
ne
Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2: 90-100
la
mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100% Respiratory acidosis and alkalosis are marked by changes
in PCO2. Higher = acidosis and lower = alkalosis Metabolic acidosis and alkalosis are caused by
something other than abnormal CO2 levels. This could include toxicity, diabetes, renal failure or
sh
Sp
excessive GI losses. Here are the rules to follow to determine if is respiratory or metabolic in
nature. -If pH and PCO2 are moving in opposite directions, then it is the pCO2 levels that are
la
, t
ne
causing the imbalance and it is respiratory in nature. -If PCO2 is normal or is moving tin the same
sh
direction as the pH, then the imbalance is metabolic in nature.
ne
6. The anion gap is the difference between measured cations (Na+ and K+) and
la
measured anions (Cl- and HCO3-), this calculation can be useful in determining
the cause of metabolic acidosis. Why would an increased anion gap be
tz
sh
Sp
observed in diabetic ketoacidosis or lactic acidosis?
ne
The anion gap is the calculation of unmeasured anions in the blood. Lactic acid and ketones
la
both lead to the production of unmeasured anions, which remove HCO3- (a measured anion) due
to buffering of the excess H+ and therefore leads to an increase in the AG.
sh
Sp
7. Why is it important to maintain a homeostatic balance of glucose in the blood
ne
(ie describe the pathogenesis of diabetes)?
la
Insulin is the hormone responsible for initiating the uptake of glucose by the cells. Cells use
glucose to produce energy (ATP). In a normal individual, when blood glucose increases, the pancreas
tz
is signaled to produced in insulin, which binds to insulin receptors on a cells surface and initiates
sh
Sp
the uptake of glucose. Glucose is a very reactive molecule and if left in the blood, it can start to
bind to other proteins and lipids, which can lead to loss of function. AGEs are advanced glycation
ne
end products that are a result of glucose reacting with the endothelial lining, which can lead to
la
damage in the heart and kidneys.
sh
Sp
8. Compare and contrast Type I and Type II Diabetes
ne
Type I diabetes is caused by lack of insulin. With out insulin signaling, glucose will not be
taken into the cell and leads to high blood glucose (hyperglycemia). Type I is usually treated with
la
insulin injections. Type II diabetes is caused by a desensitization to insulin signaling. The insulin
receptors are no longer responding to insulin, which also leads to hyperglycemia. Type II is usually
tz
sh
Sp
treated with drugs to increase the sensitization to insulin (metformin), dietary and life-style changes
or insulin injections.
ne
9. Describe some reasons for a patient needing dialysis AEIOU-
la
acidosis. Electrolytes, Intoxication/Ingestion, overload, uremia. Patients with kidney or heart
failure. A build up of phosphates, urea and magnesium are removed from the blood using a
sh
Sp
semipermeable membrane and dialysate. AEIOU: A—acidosis; E —electrolytes principally
hyperkalemia; I—ingestions or overdose of medications/drugs;
ne
O—overload of fluid causing heart failure; U—uremia leading to encephalitis/pericarditis.
la
10. Compare and contrast hemodialysis and peritoneal dialysis. What are
tz
sh
Sp
some reasons for a patient choosing one over the other?
Hemodialysis uses a machine to pump blood from the body in one tube while dialysate
ne
(made of water, electrolytes and salts) is pumped in the separate tube in the opposite direction.
la
Waste from the blood diffuses through the semipermeable membrane separating the blood from the
dialysate. Peritoneal Dialysis does not use a machine, but instead injects a solution of water and
glucose into the abdominal cavity. The peritoneum acts as the membrane instead of dialysis tubing.
sh
Sp
The waste products diffuse into the abdominal cavity and the waste solution is then drained from
the body. Peritoneal dialysis offers continuous filtration and is less disruption to the patient’s daily
ne
routines. However, it does require some training of the patient and is not recommended for
la
individuals who are overweight or have severe kidney failure. Hemodialysis provides medical care,
but 3 times a week for several hours sitting at a hospital or clinic. Individuals with acute kidney
tz
sh
Sp
failure are recommended to use hemo
ne
la
sh
Sp
la
, t
ne
sh
11. Essential Question: How does homeostasis and maintaining optimal
physiological health impact your wellbeing?
ne
la
Homeostasis acts to create a constant and stable environment in the body despite internal
and external changes. Proteins and other cellular processes require optimal conditions in order to
tz
carry out their functions. Alterations in pH, salt concentration, temperature, glucose levels, etc.
sh
Sp
can have negative effects on health, so it is vital for mechanisms that regulate homeostasis to
function properly for maintaining good health.
ne
la
Lesson 2: Cellular Response and
sh
Sp
Adaptation
ne
la
1. Differentiate between Innate Immunity and Adaptive Immunity.
tz
sh
Sp
The innate immune system encompasses physical barriers and chemical and cellular
defenses. Physical barriers protect the body from invasion. These include things like the skin and
ne
eyelashes. Chemical barriers are defense mechanisms that can destroy harmful agent. Examples
la
include tears, mucous, and stomach acid. Cellular defenses of the innate immune response are non-
specific. These cellular defenses identify pathogens and substances that are potentially dangerous
sh
and takes steps to neutralize or destroy them. Adaptive immunity is an organism’s acquired
Sp
immunity to a specific pathogen. As such, it’s also referred to as acquired immunity. Adaptive
immunity is not immediate, nor does it always last throughout an organism’s entire lifespan,
ne
although it can. The adaptive immune response is marked by clonal expansion of T and B
la
lymphocytes, releasing many antibody copies to neutralize or destroy their target antigen.
tz
sh
Sp
2. What is a way that Adaptive Immunity can recruit innate immunity?
ne
The innate immune response to microbes stimulates adaptive immune responses and
influences the nature of the adaptive responses. Conversely, adaptive immune responses often work
by enhancing the protective mechanisms of innate immunity, making them more capable of
effectively combating pathogenic microbes.
la
sh
Sp
3.3. Why are some infections harder on children while other infections are
harder on the elderly?
ne
la
tz
Children have not been exposed to many pathogens yet, so they lack memory cells and have not built-
sh
Sp
up immunity yet. The elderly have a depleted naïve T cell population from years of battling infections, so the
likelihood of getting a match is less.
ne
la
4. Describe how and why our injury response results in the signs of
redness, swelling, heat, and pain? Be sure to use chemokines, histamine,
sh
Sp
and vasodilation in your response.
ne
An injury causes an inflammatory response which is responsible for the redness, swelling,
la
heat and pain. Upon injury, cells on the surface begin to release chemokines which act as
messengers that something has happened. Mast cells are also alerted to release histamines which
tz
travel to the endothelial cells of capillaries and causes vasodilation, which is related to swelling
sh
Sp
and redness. Vasodilation also causes the capillaries to become leaky which allows for histamines,
chemokines and even pathogen particles to enter the blood stream where they are met by
ne
neutrophils (non-specific) which start to adhere to the capillary wall and squeeze through the leaky
la
holes (diapedesis or extravasation) to phagocytose pathogens and damaged cells. Dendritic cells
just under the surface of skin are also activated to phagocytose foreign particles. Other B cells, T
sh
Sp
la
ne
WGU D236 PATHOPHYSIOLOGY FINAL EXAM 180 QUESTIONS AND CORRECT DETAILED
sh
ANSWERS LATEST UPDATE 2023-2024
ne
la
tz
sh
Sp
ne
1. What is Starling's Law of Capillary forces? How does this explain why a
la
nutritionally deficient child would have edema?
Starling’s Law describes how fluids move across the capillary membrane. There are two
sh
Sp
major opposing forces that act to balance each other, hydrostatic pressure (pushing water out of
the capillaries) and osmotic pressure (including oncontic pressure, which pushes fluid into the
ne
capillaries). Both electrolytes and proteins (oncontic pressure) in the blood affect osmotic pressure,
high electrolyte and protein concentrations in the blood would cause water to leave the cells and
la
interstitial space and enter the blood stream to dilute the high concentrations. On, the other hand,
tz
low electrolyte and protein concentrations (as seen in a nutritionally deficient child) would cause
sh
Sp
water to leave the capillaries and enter the cells and interstitial fluid which can lead to edema.
ne
2. How does the RAAS (Renin-Angiotensin-Aldosterone System) result in
la
increased blood volume and increased blood pressure?
sh
Sp
A drop in blood pressure is sensed by the kidneys by low perfusion, which in turn begins to
secrete renin. Renin then triggers the liver to produce angiotensinogen, which is converted to
ne
Angiotensin I in the lungs and then angiotensin II by the enzyme Angiotensin-converting enzyme
(ACE). Angiotensin II stimulates peripheral arterial vasoconstriction which raises BP. Angiotensin II is
la
also stimulating the adrenal gland to release aldosterone, which acts to increase sodium and water
tz
reabsorption increasing blood volume, while also increased potassium secretion in urine.
sh
Sp
ne
3. How can hyperkalemia lead to cardiac arrest?
la
Normal levels of potassium are between 3.5 and 5.2 mEq/dL. Hyperkalemia refers to
sh
potassium levels higher that 5.2 mEq/dL. A major function of potassium is to conduct nerve impulses
Sp
in muscles. Too low and muscle weakness occurs and too much can cause muscle spasms. This is
especially dangerous in the heart muscle and an irregular heartbeat can cause a heart attack.
ne
la
4. The body uses the Protein Buffering System, Phosphate Buffering System, and
tz
Carbonic Acid-Bicarbonate System to regulate and maintain homeostatic pH,
sh
Sp
what is the consequence of a pH imbalance?
ne
Proteins contain many acidic and basic group that can be affected by pH changes. Any
la
increase or decrease in blood pH can alter the structure of the protein (denature), thereby
affecting its function as well.
sh
Sp
5. Describe the laboratory findings associated with metabolic
Want to earn $103 per month?
ne
la
acidosis, metabolic alkalosis, respiratory acidosis and respiratory alkalosis. (ie
tz
relative pH and CO2 levels).
sh
Sp
ne
Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2: 90-100
la
mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100% Respiratory acidosis and alkalosis are marked by changes
in PCO2. Higher = acidosis and lower = alkalosis Metabolic acidosis and alkalosis are caused by
something other than abnormal CO2 levels. This could include toxicity, diabetes, renal failure or
sh
Sp
excessive GI losses. Here are the rules to follow to determine if is respiratory or metabolic in
nature. -If pH and PCO2 are moving in opposite directions, then it is the pCO2 levels that are
la
, t
ne
causing the imbalance and it is respiratory in nature. -If PCO2 is normal or is moving tin the same
sh
direction as the pH, then the imbalance is metabolic in nature.
ne
6. The anion gap is the difference between measured cations (Na+ and K+) and
la
measured anions (Cl- and HCO3-), this calculation can be useful in determining
the cause of metabolic acidosis. Why would an increased anion gap be
tz
sh
Sp
observed in diabetic ketoacidosis or lactic acidosis?
ne
The anion gap is the calculation of unmeasured anions in the blood. Lactic acid and ketones
la
both lead to the production of unmeasured anions, which remove HCO3- (a measured anion) due
to buffering of the excess H+ and therefore leads to an increase in the AG.
sh
Sp
7. Why is it important to maintain a homeostatic balance of glucose in the blood
ne
(ie describe the pathogenesis of diabetes)?
la
Insulin is the hormone responsible for initiating the uptake of glucose by the cells. Cells use
glucose to produce energy (ATP). In a normal individual, when blood glucose increases, the pancreas
tz
is signaled to produced in insulin, which binds to insulin receptors on a cells surface and initiates
sh
Sp
the uptake of glucose. Glucose is a very reactive molecule and if left in the blood, it can start to
bind to other proteins and lipids, which can lead to loss of function. AGEs are advanced glycation
ne
end products that are a result of glucose reacting with the endothelial lining, which can lead to
la
damage in the heart and kidneys.
sh
Sp
8. Compare and contrast Type I and Type II Diabetes
ne
Type I diabetes is caused by lack of insulin. With out insulin signaling, glucose will not be
taken into the cell and leads to high blood glucose (hyperglycemia). Type I is usually treated with
la
insulin injections. Type II diabetes is caused by a desensitization to insulin signaling. The insulin
receptors are no longer responding to insulin, which also leads to hyperglycemia. Type II is usually
tz
sh
Sp
treated with drugs to increase the sensitization to insulin (metformin), dietary and life-style changes
or insulin injections.
ne
9. Describe some reasons for a patient needing dialysis AEIOU-
la
acidosis. Electrolytes, Intoxication/Ingestion, overload, uremia. Patients with kidney or heart
failure. A build up of phosphates, urea and magnesium are removed from the blood using a
sh
Sp
semipermeable membrane and dialysate. AEIOU: A—acidosis; E —electrolytes principally
hyperkalemia; I—ingestions or overdose of medications/drugs;
ne
O—overload of fluid causing heart failure; U—uremia leading to encephalitis/pericarditis.
la
10. Compare and contrast hemodialysis and peritoneal dialysis. What are
tz
sh
Sp
some reasons for a patient choosing one over the other?
Hemodialysis uses a machine to pump blood from the body in one tube while dialysate
ne
(made of water, electrolytes and salts) is pumped in the separate tube in the opposite direction.
la
Waste from the blood diffuses through the semipermeable membrane separating the blood from the
dialysate. Peritoneal Dialysis does not use a machine, but instead injects a solution of water and
glucose into the abdominal cavity. The peritoneum acts as the membrane instead of dialysis tubing.
sh
Sp
The waste products diffuse into the abdominal cavity and the waste solution is then drained from
the body. Peritoneal dialysis offers continuous filtration and is less disruption to the patient’s daily
ne
routines. However, it does require some training of the patient and is not recommended for
la
individuals who are overweight or have severe kidney failure. Hemodialysis provides medical care,
but 3 times a week for several hours sitting at a hospital or clinic. Individuals with acute kidney
tz
sh
Sp
failure are recommended to use hemo
ne
la
sh
Sp
la
, t
ne
sh
11. Essential Question: How does homeostasis and maintaining optimal
physiological health impact your wellbeing?
ne
la
Homeostasis acts to create a constant and stable environment in the body despite internal
and external changes. Proteins and other cellular processes require optimal conditions in order to
tz
carry out their functions. Alterations in pH, salt concentration, temperature, glucose levels, etc.
sh
Sp
can have negative effects on health, so it is vital for mechanisms that regulate homeostasis to
function properly for maintaining good health.
ne
la
Lesson 2: Cellular Response and
sh
Sp
Adaptation
ne
la
1. Differentiate between Innate Immunity and Adaptive Immunity.
tz
sh
Sp
The innate immune system encompasses physical barriers and chemical and cellular
defenses. Physical barriers protect the body from invasion. These include things like the skin and
ne
eyelashes. Chemical barriers are defense mechanisms that can destroy harmful agent. Examples
la
include tears, mucous, and stomach acid. Cellular defenses of the innate immune response are non-
specific. These cellular defenses identify pathogens and substances that are potentially dangerous
sh
and takes steps to neutralize or destroy them. Adaptive immunity is an organism’s acquired
Sp
immunity to a specific pathogen. As such, it’s also referred to as acquired immunity. Adaptive
immunity is not immediate, nor does it always last throughout an organism’s entire lifespan,
ne
although it can. The adaptive immune response is marked by clonal expansion of T and B
la
lymphocytes, releasing many antibody copies to neutralize or destroy their target antigen.
tz
sh
Sp
2. What is a way that Adaptive Immunity can recruit innate immunity?
ne
The innate immune response to microbes stimulates adaptive immune responses and
influences the nature of the adaptive responses. Conversely, adaptive immune responses often work
by enhancing the protective mechanisms of innate immunity, making them more capable of
effectively combating pathogenic microbes.
la
sh
Sp
3.3. Why are some infections harder on children while other infections are
harder on the elderly?
ne
la
tz
Children have not been exposed to many pathogens yet, so they lack memory cells and have not built-
sh
Sp
up immunity yet. The elderly have a depleted naïve T cell population from years of battling infections, so the
likelihood of getting a match is less.
ne
la
4. Describe how and why our injury response results in the signs of
redness, swelling, heat, and pain? Be sure to use chemokines, histamine,
sh
Sp
and vasodilation in your response.
ne
An injury causes an inflammatory response which is responsible for the redness, swelling,
la
heat and pain. Upon injury, cells on the surface begin to release chemokines which act as
messengers that something has happened. Mast cells are also alerted to release histamines which
tz
travel to the endothelial cells of capillaries and causes vasodilation, which is related to swelling
sh
Sp
and redness. Vasodilation also causes the capillaries to become leaky which allows for histamines,
chemokines and even pathogen particles to enter the blood stream where they are met by
ne
neutrophils (non-specific) which start to adhere to the capillary wall and squeeze through the leaky
la
holes (diapedesis or extravasation) to phagocytose pathogens and damaged cells. Dendritic cells
just under the surface of skin are also activated to phagocytose foreign particles. Other B cells, T
sh
Sp
la
