WGU D236 Pathophysiology OA and Pre- Assessment Exam
What is Starling's Law of Capillary forces? 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
How does this explain why a nutritionally deficient child (pushing water out of the capillaries) and osmotic pressure (including oncontic
would have edema? 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.
How does the RAAS (Renin-Angiotensin-Aldosterone A drop in blood pressure is sensed by the kidneys by low perfusion, which in turn
System) result in increased blood volume and increased begins to secrete renin.
blood pressure?
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.
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
The body uses the Protein Buffering System, Phosphate Proteins contain many acidic and basic group that can be affected by pH changes.
Buffering System, and Carbonic Acid-Bicarbonate System Any increase or decrease in blood pH can alter the structure of the protein
to regulate and maintain homeostatic pH, what is the (denature), thereby affecting its function as well
consequence of a pH imbalance
Describe the laboratory findings associated with metabolic Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg
acidosis, metabolic alkalosis, respiratory acidosis and PO2: 90-100 mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100%
respiratory alkalosis. (ie relative pH and CO2 levels).
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 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
causing the imbalance and it is respiratory in nature.
-If PCO2 is normal or is moving in the same direction as the pH, then the imbalance
is metabolic in nature.
The anion gap is the difference between measured cations The anion gap is the calculation of unmeasured anions in the blood.
(Na+ and K+) and measured anions (Cl- and HCO3-), this
calculation can be useful in determining the cause of Lactic acid and ketones both lead to the production of unmeasured anions, which
metabolic acidosis. remove HCO3- (a measured anion) due to buffering of the excess H+ and therefore
leads to an increase in the AG.
Why would an increased anion gap be observed in
diabetic ketoacidosis or lactic acidosis?
, WGU D236 Pathophysiology OA and Pre- Assessment Exam
Why is it important to maintain a homeostatic balance of Insulin is the hormone responsible for initiating the uptake of glucose by the cells.
glucose in the blood (ie describe the pathogenesis of Cells use glucose to produce energy (ATP).
diabetes)?
In a normal individual, when blood glucose increases, the pancreas is signaled to
produced in insulin, which binds to insulin receptors on a cells surface and initiates
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 end products that are a result of glucose reacting with
the endothelial lining, which can lead to damage in the heart and kidneys.
Compare and contrast Type I and Type II Diabetes 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 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 treated with drugs to increase the sensitization to insulin
(metformin), dietary and life-style changes or insulin injections.
Describe some reasons for a patient needing dialysis AEIOU-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
semi-permeable membrane and dialysate.
AEIOU:
A—acidosis;
E—electrolytes principally hyperkalemia;
I—ingestions or overdose of medications/drugs;
O—overload of fluid causing heart failure;
U—uremia leading to encephalitis/pericarditis
Compare and contrast hemodialysis and peritoneal Hemodialysis uses a machine to pump blood from the body in one tube while
dialysis. dialysate (made of water, electrolytes and salts) is pumped in the separate tube in
the opposite direction. Waste from the blood diffuses through the semipermeable
What are some reasons for a patient choosing one over membrane separating the blood from the dialysate.
the other?
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. 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 routines. However, it does require some training of the patient and is not
recommended for 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 failure are recommended to use
hemodialysis.
How does homeostasis and maintaining optimal Homeostasis acts to create a constant and stable environment in the body despite
physiological health impact your wellbeing? internal and external changes. Proteins and other cellular processes require optimal
conditions in order to carry out their functions.
Alterations in pH, salt concentration, temperature, glucose levels, etc. can have
negative effects on health, so it is vital for mechanisms that regulate homeostasis to
function properly for maintaining good health
, WGU D236 Pathophysiology OA and Pre- Assessment Exam
Differentiate between Innate Immunity and Adaptive The innate immune system encompasses physical barriers and chemical and
Immunity ? cellular defenses. Physical barriers protect the body from invasion. These include
things like the skin and eyelashes. Chemical barriers are defense mechanisms that
can destroy harmful agent. Examples 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 and
takes steps to neutralize or destroy them.
Adaptive immunity is an organism's acquired 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, although it can.
The adaptive immune response is marked by clonal expansion of T and B
lymphocytes, releasing many antibody copies to neutralize or destroy their target
antigen
What is a way that Adaptive Immunity can recruit innate The innate immune response to microbes stimulates adaptive immune responses
immunity? 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
Why are some infections harder on children while other Children have not been exposed to many pathogens yet, so they lack memory cells
infections are harder on the elderly? and have not built-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.
Describe how and why our injury response results in the An injury causes an inflammatory response which is responsible for the redness,
signs of redness, swelling, heat, and pain? swelling, heat and pain. Upon injury, cells on the surface begin to release
chemokines which act as messengers that something has happened.
(Be sure to use chemokines, histamine, and vasodilation in
your response.) Mast cells are also alerted to release histamines which travel to the endothelial cells
of capillaries and causes vasodilation, which is related to swelling 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 neutrophils (non-specific) which start to adhere to the
capillary wall and squeeze through the leaky 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 cells (specific) and the complement system also
squeeze through the capillary wall to create an area of congestion.
Explain dominant vs recessive genetic diseases. The human genome contains 23 pairs of chromosome (22 autosomes and 1 pair of
What is a "carrier" in recessive genetic diseases? sex chromosomes). The pairs are homologous and contain the same genes in the
same order. This means that every gene has a copy, one inherited from your mother
and the other from your father.
Not all versions of a gene (alleles) are treated the same by the cell. Some are
expressed over others. A dominant gene is a gene that is expressed, even if you
only have one copy. The dominant gene will be expressed over the recessive gene,
which must have two copies to be expressed.
In a dominant genetic disease, all it takes is one copy of the disease to have the
disease. Recessive genetic diseases require that the individual gets two copies of
the gene to have the disease.
Someone who is a carrier for a recessive genetic disease is healthy, but contains a
copy of the disease gene, potentially passing it to their offspring.
Describe how to determine the probability of clinical Punnett Squares can be used to determine the potential probabilities of certain
outcomes given information about the parents (eg two traits being passed to offspring. If you know the genotypes of each parent (ie
heterozygous carriers of sickle cell disease). homozygous or heterozygous for the trait), you can determine the possible
outcomes.
Heterozygous means that the parent has one copy of each gene, homozygous
means the parent has the same copy for each gene (either both dominant genes or
both recessive genes).
What is Starling's Law of Capillary forces? 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
How does this explain why a nutritionally deficient child (pushing water out of the capillaries) and osmotic pressure (including oncontic
would have edema? 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.
How does the RAAS (Renin-Angiotensin-Aldosterone A drop in blood pressure is sensed by the kidneys by low perfusion, which in turn
System) result in increased blood volume and increased begins to secrete renin.
blood pressure?
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.
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
The body uses the Protein Buffering System, Phosphate Proteins contain many acidic and basic group that can be affected by pH changes.
Buffering System, and Carbonic Acid-Bicarbonate System Any increase or decrease in blood pH can alter the structure of the protein
to regulate and maintain homeostatic pH, what is the (denature), thereby affecting its function as well
consequence of a pH imbalance
Describe the laboratory findings associated with metabolic Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45 PCO2: 35-45 mm Hg
acidosis, metabolic alkalosis, respiratory acidosis and PO2: 90-100 mm Hg HCO3-: 22-26 mEq/L SaO2: 95-100%
respiratory alkalosis. (ie relative pH and CO2 levels).
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 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
causing the imbalance and it is respiratory in nature.
-If PCO2 is normal or is moving in the same direction as the pH, then the imbalance
is metabolic in nature.
The anion gap is the difference between measured cations The anion gap is the calculation of unmeasured anions in the blood.
(Na+ and K+) and measured anions (Cl- and HCO3-), this
calculation can be useful in determining the cause of Lactic acid and ketones both lead to the production of unmeasured anions, which
metabolic acidosis. remove HCO3- (a measured anion) due to buffering of the excess H+ and therefore
leads to an increase in the AG.
Why would an increased anion gap be observed in
diabetic ketoacidosis or lactic acidosis?
, WGU D236 Pathophysiology OA and Pre- Assessment Exam
Why is it important to maintain a homeostatic balance of Insulin is the hormone responsible for initiating the uptake of glucose by the cells.
glucose in the blood (ie describe the pathogenesis of Cells use glucose to produce energy (ATP).
diabetes)?
In a normal individual, when blood glucose increases, the pancreas is signaled to
produced in insulin, which binds to insulin receptors on a cells surface and initiates
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 end products that are a result of glucose reacting with
the endothelial lining, which can lead to damage in the heart and kidneys.
Compare and contrast Type I and Type II Diabetes 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 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 treated with drugs to increase the sensitization to insulin
(metformin), dietary and life-style changes or insulin injections.
Describe some reasons for a patient needing dialysis AEIOU-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
semi-permeable membrane and dialysate.
AEIOU:
A—acidosis;
E—electrolytes principally hyperkalemia;
I—ingestions or overdose of medications/drugs;
O—overload of fluid causing heart failure;
U—uremia leading to encephalitis/pericarditis
Compare and contrast hemodialysis and peritoneal Hemodialysis uses a machine to pump blood from the body in one tube while
dialysis. dialysate (made of water, electrolytes and salts) is pumped in the separate tube in
the opposite direction. Waste from the blood diffuses through the semipermeable
What are some reasons for a patient choosing one over membrane separating the blood from the dialysate.
the other?
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. 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 routines. However, it does require some training of the patient and is not
recommended for 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 failure are recommended to use
hemodialysis.
How does homeostasis and maintaining optimal Homeostasis acts to create a constant and stable environment in the body despite
physiological health impact your wellbeing? internal and external changes. Proteins and other cellular processes require optimal
conditions in order to carry out their functions.
Alterations in pH, salt concentration, temperature, glucose levels, etc. can have
negative effects on health, so it is vital for mechanisms that regulate homeostasis to
function properly for maintaining good health
, WGU D236 Pathophysiology OA and Pre- Assessment Exam
Differentiate between Innate Immunity and Adaptive The innate immune system encompasses physical barriers and chemical and
Immunity ? cellular defenses. Physical barriers protect the body from invasion. These include
things like the skin and eyelashes. Chemical barriers are defense mechanisms that
can destroy harmful agent. Examples 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 and
takes steps to neutralize or destroy them.
Adaptive immunity is an organism's acquired 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, although it can.
The adaptive immune response is marked by clonal expansion of T and B
lymphocytes, releasing many antibody copies to neutralize or destroy their target
antigen
What is a way that Adaptive Immunity can recruit innate The innate immune response to microbes stimulates adaptive immune responses
immunity? 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
Why are some infections harder on children while other Children have not been exposed to many pathogens yet, so they lack memory cells
infections are harder on the elderly? and have not built-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.
Describe how and why our injury response results in the An injury causes an inflammatory response which is responsible for the redness,
signs of redness, swelling, heat, and pain? swelling, heat and pain. Upon injury, cells on the surface begin to release
chemokines which act as messengers that something has happened.
(Be sure to use chemokines, histamine, and vasodilation in
your response.) Mast cells are also alerted to release histamines which travel to the endothelial cells
of capillaries and causes vasodilation, which is related to swelling 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 neutrophils (non-specific) which start to adhere to the
capillary wall and squeeze through the leaky 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 cells (specific) and the complement system also
squeeze through the capillary wall to create an area of congestion.
Explain dominant vs recessive genetic diseases. The human genome contains 23 pairs of chromosome (22 autosomes and 1 pair of
What is a "carrier" in recessive genetic diseases? sex chromosomes). The pairs are homologous and contain the same genes in the
same order. This means that every gene has a copy, one inherited from your mother
and the other from your father.
Not all versions of a gene (alleles) are treated the same by the cell. Some are
expressed over others. A dominant gene is a gene that is expressed, even if you
only have one copy. The dominant gene will be expressed over the recessive gene,
which must have two copies to be expressed.
In a dominant genetic disease, all it takes is one copy of the disease to have the
disease. Recessive genetic diseases require that the individual gets two copies of
the gene to have the disease.
Someone who is a carrier for a recessive genetic disease is healthy, but contains a
copy of the disease gene, potentially passing it to their offspring.
Describe how to determine the probability of clinical Punnett Squares can be used to determine the potential probabilities of certain
outcomes given information about the parents (eg two traits being passed to offspring. If you know the genotypes of each parent (ie
heterozygous carriers of sickle cell disease). homozygous or heterozygous for the trait), you can determine the possible
outcomes.
Heterozygous means that the parent has one copy of each gene, homozygous
means the parent has the same copy for each gene (either both dominant genes or
both recessive genes).
