WGU D236 PATHOPHYSIOLOGY FINAL
EXAM ALL 180 QUESTIONS AND
VERIFIED ANSWERS WITH RATIONALES
LATEST 2022-2023/ WGU D236
PATHOPHYSIOLOGY FINAL EXAM ALL
LESSONS
,1. What is Starling's Law of Capillary forces? How does this
explain why a nutritionally deficient child would have edema?
Starling’s Law describes how fluids move across the capillary membrane. There
are two 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 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 interstitial space
and enter the blood stream to dilute the high concentrations. On, the other hand, low
electrolyte and protein concentrations (as seen in a nutritionally deficient child) would
cause water to leave the capillaries and enter the cells and interstitial fluid which can
lead to edema.
2. How does the RAAS (Renin-Angiotensin-Aldosterone System)
result in increased blood volume and increased blood
pressure?
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 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 also stimulating the adrenal gland to
release aldosterone, which acts to increase sodium and water reabsorption increasing
blood volume, while also increased potassium secretion in urine.
3. How can hyperkalemia lead to cardiac arrest?
Normal levels of potassium are between 3.5 and 5.2 mEq/dL. Hyperkalemia refers
to potassium levels higher that 5.2 mEq/dL. A major function of potassium is to conduct
nerve impulses 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.
4. The body uses the Protein Buffering System, Phosphate
Buffering System, and Carbonic Acid-Bicarbonate System to
regulate and maintain homeostatic pH, what is the
consequence of a pH imbalance?
Proteins contain many acidic and basic group that can be affected by pH
changes. Any increase or decrease in blood pH can alter the structure of the protein
(denature), thereby affecting its function as well.
5. Describe the laboratory findings associated with metabolic
Want to earn $103 per month?
, acidosis, metabolic alkalosis, respiratory acidosis and
respiratory alkalosis. (ie relative pH and CO2 levels).
Want to earn $103 per month?
EXAM ALL 180 QUESTIONS AND
VERIFIED ANSWERS WITH RATIONALES
LATEST 2022-2023/ WGU D236
PATHOPHYSIOLOGY FINAL EXAM ALL
LESSONS
,1. What is Starling's Law of Capillary forces? How does this
explain why a nutritionally deficient child would have edema?
Starling’s Law describes how fluids move across the capillary membrane. There
are two 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 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 interstitial space
and enter the blood stream to dilute the high concentrations. On, the other hand, low
electrolyte and protein concentrations (as seen in a nutritionally deficient child) would
cause water to leave the capillaries and enter the cells and interstitial fluid which can
lead to edema.
2. How does the RAAS (Renin-Angiotensin-Aldosterone System)
result in increased blood volume and increased blood
pressure?
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 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 also stimulating the adrenal gland to
release aldosterone, which acts to increase sodium and water reabsorption increasing
blood volume, while also increased potassium secretion in urine.
3. How can hyperkalemia lead to cardiac arrest?
Normal levels of potassium are between 3.5 and 5.2 mEq/dL. Hyperkalemia refers
to potassium levels higher that 5.2 mEq/dL. A major function of potassium is to conduct
nerve impulses 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.
4. The body uses the Protein Buffering System, Phosphate
Buffering System, and Carbonic Acid-Bicarbonate System to
regulate and maintain homeostatic pH, what is the
consequence of a pH imbalance?
Proteins contain many acidic and basic group that can be affected by pH
changes. Any increase or decrease in blood pH can alter the structure of the protein
(denature), thereby affecting its function as well.
5. Describe the laboratory findings associated with metabolic
Want to earn $103 per month?
, acidosis, metabolic alkalosis, respiratory acidosis and
respiratory alkalosis. (ie relative pH and CO2 levels).
Want to earn $103 per month?
