1.
Most bosy water comes from ________, whereas most body water is lost via _____.
Correct Answer
D. Drinking; urine
Explanation
The correct answer is "drinking; urine". The majority of body water is obtained through drinking fluids, while the majority of body water is lost through the production of urine.
2.
In a state of water balance, average daily fluid gains and losses are equal.
Correct Answer
A. True
Explanation
In a state of water balance, the average daily fluid gains and losses are equal. This means that the amount of water taken in through drinking, eating, and metabolic processes is equal to the amount of water lost through urine, sweat, and respiration. This balance is important for maintaining proper hydration and bodily functions.
3.
A weak base
Correct Answer
C. Binds little H+ and has weak effect on pH
Explanation
A weak base binds little H+ and has a weak effect on pH because it does not dissociate completely in water, resulting in a low concentration of H+ ions. This weak binding of H+ ions leads to a minimal impact on the overall pH of the solution.
4.
A renal calculus can be up to 2 cm wide, but even then, it would not obstruct
Correct Answer
D. The urinary bladder
Explanation
A renal calculus, also known as a kidney stone, can grow up to 2 cm in size. However, even at this size, it would not obstruct the urinary bladder. The urinary bladder is a muscular organ that stores urine before it is expelled from the body. Kidney stones can cause blockages and pain when they pass through the urinary system, but they typically do not obstruct the bladder.
5.
Calcium concentration is regulated by
Correct Answer
A. Hormones
Explanation
Calcium concentration in the body is regulated by hormones. Hormones such as parathyroid hormone (PTH) and calcitonin play a crucial role in maintaining calcium homeostasis. PTH increases blood calcium levels by stimulating the release of calcium from bones and enhancing its reabsorption in the kidneys. Calcitonin, on the other hand, decreases blood calcium levels by inhibiting bone resorption and promoting calcium excretion in the kidneys. These hormones work together to ensure that calcium levels in the body remain within a narrow range, which is essential for various physiological processes.
6.
Ethyl (drinking) alcohol stimulates the secretion of AVP, thereby reducing reabsorption bu the collecting duct.
Correct Answer
B. False
Explanation
False. Ethyl alcohol actually inhibits the secretion of AVP (antidiuretic hormone), which leads to increased reabsorption by the collecting duct.
7.
Long-term inhibition of thirst is mostly associated with
Correct Answer
C. A drop in blood osmolarity
Explanation
Long-term inhibition of thirst is mostly associated with a drop in blood osmolarity. When the blood osmolarity decreases, it means that the concentration of solutes in the blood is lower. This signals to the brain that the body is adequately hydrated and there is no need for further water intake. In response to this signal, the brain inhibits the sensation of thirst, leading to a decrease in the desire to drink water.
8.
PCTs are responsible for reabsorbing all of the following except
Correct Answer
C. Hydrogen ions
Explanation
PCTs, or proximal convoluted tubules, play a crucial role in reabsorbing various substances in the kidney. They reabsorb potassium, sodium chloride, urea, and water to maintain the body's balance. However, they do not reabsorb hydrogen ions. These ions are typically regulated by other parts of the nephron, such as the distal convoluted tubules and collecting ducts. Therefore, the correct answer is hydrogen ions.
9.
Total saturation of protein transporters for a given solute in the renal tubules would result in
Correct Answer
D. Appearance of that solute in urine
Explanation
When the protein transporters in the renal tubules are fully saturated, it means that they are unable to transport any more of the solute. As a result, the solute cannot be reabsorbed by the tubules and instead, it will be excreted in the urine. Therefore, the appearance of that solute in the urine is the expected outcome when the protein transporters are fully saturated.
10.
Which of the following is a direct result of antidiuretic hormones?
Correct Answer
A. Decreased urine volume
Explanation
Antidiuretic hormones, such as vasopressin, act on the kidneys to increase water reabsorption, leading to decreased urine volume. This hormone causes the kidneys to retain water and prevents excessive water loss through urine. As a result, less water is excreted in the urine, leading to a decrease in urine volume.
11.
Water output is significantly controlled through variation in
Correct Answer
E. Urine volume
Explanation
The variation in urine volume significantly controls water output. Urine volume refers to the amount of urine produced by the body, which is directly related to the amount of water excreted. When the body needs to conserve water, it reduces urine volume, resulting in less water being excreted. Conversely, when the body has excess water, it increases urine volume to eliminate the excess. Therefore, by regulating urine volume, the body can effectively control the amount of water that is lost through urine.
12.
Hypocalcemia stimulates
Correct Answer
B. Secretion of parathyroid hormone
Explanation
Hypocalcemia refers to low levels of calcium in the blood. Parathyroid hormone (PTH) is responsible for regulating calcium levels in the body. When calcium levels are low, the parathyroid glands secrete more PTH to stimulate the release of calcium from bones, increase calcium absorption in the intestines, and decrease calcium excretion in the kidneys. Therefore, the secretion of parathyroid hormone is the correct answer as it is a physiological response to hypocalcemia.
13.
Which renal structure is responsible for producing hypertonic urine by reabsorbing water while allowing metabolic wastes and NaCl to pass through?
Correct Answer
D. Collecting duct
Explanation
The collecting duct is responsible for producing hypertonic urine by reabsorbing water while allowing metabolic wastes and NaCl to pass through. This is achieved through the action of aquaporins, which allow water to be reabsorbed, and the presence of ion channels that facilitate the movement of NaCl and other solutes. As the filtrate passes through the collecting duct, water is reabsorbed back into the bloodstream, concentrating the urine and allowing for the excretion of waste products.
14.
The urine is most likely to be hypotonic when
Correct Answer
A. The body's water volume is high
Explanation
When the body's water volume is high, it means that there is an excess of water in the body. This leads to a dilution of solutes in the urine, making it hypotonic. In this state, the concentration of solutes in the urine is lower compared to the concentration in the blood. This occurs because the excess water in the body is not being effectively reabsorbed by the kidneys, resulting in a higher volume of urine with lower solute concentration.
15.
Diabetes is any metabolic disorder resulting in chronic polyuria.
Correct Answer
A. True
Explanation
The statement is true because diabetes is indeed a metabolic disorder that leads to chronic polyuria, which is excessive urination. In diabetes, the body either does not produce enough insulin or cannot effectively use the insulin it produces. This leads to high blood sugar levels, which in turn causes the kidneys to produce more urine to eliminate the excess glucose from the body. Chronic polyuria is a common symptom of diabetes and is often one of the early signs of the condition.
16.
Omosis from one fluid compartment to another is determined by
Correct Answer
B. The relative concentration of solutes in each compartment
Explanation
Osmosis is the movement of solvent molecules from an area of lower solute concentration to an area of higher solute concentration through a semipermeable membrane. Therefore, the relative concentration of solutes in each compartment determines the direction and rate of osmosis. If one compartment has a higher concentration of solutes compared to the other, water molecules will move from the compartment with lower solute concentration to the one with higher solute concentration until equilibrium is reached. The temperature difference, relative volume, size of compartments, and blood pressure do not directly affect osmosis.
17.
Which are primarily responsible for maintaing the salinity gradient if the renal medulla?
Correct Answer
B. Juxtamedullary nepHrons
Explanation
Juxtamedullary nephrons are primarily responsible for maintaining the salinity gradient in the renal medulla. These nephrons have long loops of Henle that extend deep into the medulla, allowing for the reabsorption of water and solutes. This reabsorption creates a concentration gradient in the medulla, with higher concentrations of solutes towards the inner region. This gradient is important for the reabsorption of water and the production of concentrated urine. Cortical nephrons, collecting ducts, proximal convoluted tubules, and distal convoluted tubules also play roles in urine formation, but they do not contribute significantly to the maintenance of the salinity gradient in the renal medulla.
18.
In the nephron, the fluid that immediately preceds urine is known as
Correct Answer
C. Tubular fluid
Explanation
In the nephron, the fluid that immediately precedes urine is known as tubular fluid. This fluid is formed after the glomerular filtrate passes through the renal tubules, where reabsorption and secretion occur. The tubular fluid contains waste products, excess water, and electrolytes that were not reabsorbed by the body. It undergoes further concentration and modification as it travels through the renal tubules before being excreted as urine.
19.
Fluid intake is governed mainly by hypothalamic neurons called
Correct Answer
D. Osmoreceptors
Explanation
Osmoreceptors are hypothalamic neurons that play a crucial role in regulating fluid intake. These specialized cells detect changes in the osmotic pressure of the blood, which is a measure of its concentration. When the osmotic pressure increases, indicating dehydration, osmoreceptors send signals to the brain to stimulate thirst and increase fluid intake. Conversely, when the osmotic pressure decreases, indicating excess fluid, osmoreceptors inhibit thirst and decrease fluid intake. Therefore, osmoreceptors are responsible for maintaining the body's water balance by regulating fluid intake based on the osmotic pressure of the blood.
20.
Hypernatremia is a plasma _____ concentration above normal
Correct Answer
B. Na+
Explanation
Hypernatremia is a condition characterized by a high concentration of sodium ions (Na+) in the plasma, which is above the normal range. This can occur due to various reasons such as excessive sodium intake, inadequate water intake, or impaired kidney function. The elevated sodium levels can disrupt the body's fluid balance and lead to symptoms like increased thirst, dry mouth, and altered mental status. Treatment typically involves addressing the underlying cause and restoring proper hydration levels.
21.
The transition from an afferent arteriole to an efferent arteriole occurs in the
Correct Answer
A. Glomerulus
Explanation
The correct answer is glomerulus. The transition from an afferent arteriole to an efferent arteriole occurs in the glomerulus. The glomerulus is a network of tiny blood vessels located within the renal corpuscle in the kidney. It is responsible for the filtration of blood and the formation of urine. The afferent arteriole brings blood into the glomerulus, where it is filtered, and the efferent arteriole carries the filtered blood away from the glomerulus.
22.
The kidneys neutralize more acid or base than any other base system
Correct Answer
A. True
Explanation
The kidneys have a crucial role in maintaining the acid-base balance in the body. They are responsible for filtering the blood and excreting excess acid or base through urine. The kidneys have the ability to regulate the levels of hydrogen ions and bicarbonate ions in the body, which helps in neutralizing excess acid or base. This makes the kidneys the primary system for acid-base regulation and explains why they neutralize more acid or base than any other system in the body.
23.
A buffer system converts a weak acid or base into a strong one.
Correct Answer
B. False
Explanation
A buffer system does not convert a weak acid or base into a strong one. Instead, it helps to maintain the pH of a solution by resisting changes in acidity or alkalinity when small amounts of acid or base are added. A buffer system consists of a weak acid and its conjugate base (or a weak base and its conjugate acid), which can react with added acid or base to minimize the change in pH.
24.
Uncompensated alkalosis is a pH inbalance that can only be corrected with clinical intervention.
Correct Answer
A. True
Explanation
Uncompensated alkalosis refers to a pH imbalance in the body that cannot be naturally corrected by the body's compensatory mechanisms. This means that the body's usual methods of regulating pH levels, such as through the kidneys or lungs, are unable to restore balance on their own. As a result, clinical intervention is necessary to correct the alkalosis and bring the pH back to a normal range. Therefore, the statement "Uncompensated alkalosis is a pH imbalance that can only be corrected with clinical intervention" is true.
25.
WHich of the following does not contribute to water conservation
Correct Answer
D. Diuretics
Explanation
Diuretics are medications that increase urine production and promote fluid loss from the body. This process does not contribute to water conservation as it leads to increased excretion of water. In contrast, the collecting duct, countercurrent multiplier, and countercurrent exchange system are all mechanisms in the kidney that play a role in conserving water by reabsorbing it back into the body. The length of the nephrons also contributes to water conservation as it allows for more time and opportunity for water reabsorption.
26.
The most toxic of our metabolic wastes are nitrogenous wastes.
Correct Answer
A. True
Explanation
Nitrogenous wastes are indeed the most toxic metabolic wastes in our body. These wastes are produced during the breakdown of proteins and other nitrogen-containing compounds. If they accumulate in the body, they can cause serious harm and disrupt normal bodily functions. Therefore, it is important for our body to efficiently remove these nitrogenous wastes through processes such as urine formation.
27.
This is the greatest determinant of intracellular volume.
Correct Answer
A. K+
Explanation
Potassium (K+) is the correct answer because it is the most abundant cation inside the cells and plays a crucial role in maintaining intracellular volume. It helps regulate cell membrane potential and is involved in numerous cellular processes such as protein synthesis, cell growth, and enzyme activity. Changes in potassium levels can lead to alterations in cell volume, affecting overall cellular function. Therefore, K+ is the greatest determinant of intracellular volume.
28.
Tissue fluid normally has a pH of
Correct Answer
E. 7.35 - 7.45
Explanation
Tissue fluid normally has a pH of 7.35 - 7.45. This pH range is considered to be slightly alkaline or basic. The pH of tissue fluid is important for maintaining the proper functioning of cells and enzymes in the body. A pH outside of this range can disrupt cellular processes and lead to health issues.
29.
Normal urine from a healthy person can be expected to contain all of the following except
Correct Answer
C. Glucose
Explanation
Normal urine from a healthy person does not typically contain glucose. Glucose is normally reabsorbed by the kidneys and not excreted in urine. Its presence in urine can indicate a condition such as diabetes. Creatinine, urobilin, ammonia, and magnesium, on the other hand, are all substances that can be found in normal urine.
30.
Arginine Vasopressin (AVP), sometimes called ADH,
Correct Answer
B. Promotes water conservation
Explanation
Arginine Vasopressin (AVP), also known as ADH, promotes water conservation. This hormone is released by the pituitary gland in response to low blood volume or increased blood osmolality. AVP acts on the kidneys, causing them to reabsorb water and reduce urine output. This helps to conserve water in the body and prevent dehydration. AVP also acts on the blood vessels, causing vasoconstriction and increasing blood pressure. However, the given options do not mention the effects of AVP on angiotensin II secretion, hypothalamic osmoreceptors, inhibition of salivation and thirst, or targeting the cerebral cortex.
31.
Which of the following would reduce the glomerular filtration rate?
Correct Answer
D. Vasoconstriction of the afferent arteriole
Explanation
Vasoconstriction of the afferent arteriole would reduce the glomerular filtration rate. The afferent arteriole supplies blood to the glomerulus, where filtration occurs. When the afferent arteriole constricts, it decreases the blood flow into the glomerulus, resulting in a decrease in glomerular filtration rate. This constriction reduces the pressure within the glomerulus, which in turn decreases the filtration of fluid and solutes into the glomerular capsule.
32.
Aldosterone
Correct Answer
C. Increase Na+ reabsorption and K+ secretion
Explanation
Aldosterone is a hormone produced by the adrenal glands that plays a role in regulating the balance of sodium (Na+) and potassium (K+) in the body. Its main function is to increase the reabsorption of sodium and the secretion of potassium in the kidneys. This helps to retain sodium in the body and excrete excess potassium. Therefore, the correct answer is that aldosterone increases Na+ reabsorption and K+ secretion.
33.
In response to a drop in overall blood pressure, _____ stimulates constriction of the glomerular inlet and even greter constriction of the outlet.
Correct Answer
E. Angiotensin II
Explanation
Angiotensin II is a hormone that is released in response to a drop in overall blood pressure. It stimulates constriction of the glomerular inlet and even greater constriction of the outlet. This constriction helps to increase blood pressure and maintain adequate blood flow to the kidneys.
34.
Two solutions are separated by a selectively permeable membrane. Solution A has a higher concentration of the non permeating solute that solution B. Then,
Correct Answer
D. Water will pass down its concentration gradient from solution B to A
Explanation
When two solutions are separated by a selectively permeable membrane, water will pass down its concentration gradient from the solution with lower solute concentration (solution B) to the solution with higher solute concentration (solution A). This process is known as osmosis. The movement of water occurs in order to equalize the concentration of solutes on both sides of the membrane.
35.
Women have a tendency to retain water during part of the menstrual cycle because estrogen mimics the action of
Correct Answer
B. Aldosterone
Explanation
During the menstrual cycle, estrogen levels fluctuate, causing the body to retain water. Aldosterone is a hormone that regulates water and electrolyte balance in the body, specifically by increasing the reabsorption of sodium and water by the kidneys. Therefore, it is likely that estrogen mimics the action of aldosterone, leading to water retention in women during certain phases of their menstrual cycle.
36.
Which muscle is located in the bladder?
Correct Answer
A. Detrusor
Explanation
The detrusor muscle is located in the bladder. It is a smooth muscle that surrounds the bladder and is responsible for contracting and relaxing to help with the process of urination. The other options, such as distractor, pubococcygeus, corpus cavernosum, and corpus spongiosum, are not located in the bladder and do not have a direct role in the process of urination.
37.
A patient was severely dehydrated, losing a large amount of fluid. The patient was given intravenous fluids or normal saline. Normal saline is _______ to your blood cells and is about ______ NaCl.
Correct Answer
B. Isotonic; 0.9%
Explanation
Normal saline is isotonic to your blood cells because it has the same concentration of solutes as your blood. It is about 0.9% NaCl, which means that it contains 0.9 grams of sodium chloride per 100 milliliters of solution. This concentration is considered isotonic because it matches the osmolarity of your blood, allowing for the fluid to be effectively absorbed by your cells without causing any significant changes in cell volume or osmotic pressure.
38.
In which of these compartments would fluid accumulate in edema?
Correct Answer
C. Tissue (interstitial) fluid
Explanation
Fluid accumulates in edema in the tissue (interstitial) fluid compartment. Edema is the abnormal buildup of fluid in the interstitial spaces between cells, causing swelling and tissue damage. This can occur due to various reasons such as increased capillary permeability, impaired lymphatic drainage, or increased fluid retention. The accumulation of fluid in the interstitial spaces leads to the characteristic swelling seen in edema.
39.
The major chemical buffer systems of the body are the _______ systems
Correct Answer
C. Bicarbonate, pHospHate, protein
Explanation
The major chemical buffer systems of the body are bicarbonate, phosphate, and protein. These buffer systems help maintain the pH balance in the body by accepting or donating hydrogen ions. Bicarbonate acts as a buffer in the blood and extracellular fluid, phosphate buffers are found in intracellular fluids, and proteins act as buffers in both intracellular and extracellular fluids. Together, these buffer systems play a crucial role in regulating the acid-base balance in the body.
40.
What is the term for the pigment responsible for the color of urine?
Correct Answer
B. Urochrome
Explanation
Urochrome is the correct answer because it is the pigment responsible for the color of urine. Urochrome is a yellow pigment that is produced as a result of the breakdown of hemoglobin in the liver. It gives urine its characteristic yellow color, which can vary in intensity depending on factors such as hydration levels and certain medications or foods consumed.
41.
Micturition is another term for
Correct Answer
E. The elimination of urine
Explanation
Micturition is the process of eliminating urine from the body. It involves the contraction of the bladder muscles and relaxation of the urethral sphincter, allowing urine to flow out of the body. This term specifically refers to the act of urination and does not encompass other processes such as the production of nitrogenous wastes, glomerular filtration, inflammation of the urinary bladder, or the countercurrent multiplier process.
42.
Chloride homeostasis is achieved mainly as a result of _____ homeostasis
Correct Answer
D. Na+
Explanation
Chloride homeostasis is achieved mainly as a result of Na+ homeostasis. Sodium ions play a crucial role in maintaining the balance of chloride ions in the body. Sodium and chloride ions are often found together in the extracellular fluid, and their concentrations are tightly regulated to ensure proper cell function. Sodium ions are actively transported across cell membranes, which indirectly affects the movement of chloride ions. Therefore, any disruption in sodium homeostasis can lead to imbalances in chloride levels, highlighting the importance of Na+ in achieving chloride homeostasis.
43.
Prior to chemical tests for glycosuria, clinicians checked for sweetness of the urine as a sign of
Correct Answer
C. Diabetes mellitus
Explanation
Prior to chemical tests for glycosuria, clinicians checked for sweetness of the urine as a sign of diabetes mellitus. Diabetes mellitus is a condition characterized by high levels of glucose in the blood, which can lead to the presence of glucose in the urine. This excess glucose can give the urine a sweet taste, hence why clinicians used to rely on the sweetness of the urine as an indicator of diabetes mellitus.
44.
The bicarbonate buffer system would not work very well in the human body if not for the action of the respiratory system, which
Correct Answer
E. Expels CO2 produced by the buffer system
Explanation
The bicarbonate buffer system in the human body helps maintain the pH balance by regulating the concentration of hydrogen ions (H+). When the buffer system produces excess CO2, it needs to be expelled from the body to prevent an accumulation of carbonic acid. The respiratory system plays a crucial role in this process by expelling the CO2 through exhalation. This ensures that the bicarbonate buffer system can continue functioning effectively and maintain the pH balance in the body.
45.
Albuminuria is a common sign of diabetes mellitus
Correct Answer
B. False
Explanation
Albuminuria is not a common sign of diabetes mellitus. While diabetes mellitus can lead to kidney damage, resulting in albuminuria, it is not a common sign of the condition. Other symptoms such as increased thirst, frequent urination, unexplained weight loss, and fatigue are more commonly associated with diabetes mellitus. Therefore, the statement that albuminuria is a common sign of diabetes mellitus is false.
46.
The innermost connective tissue layer protecting the kidney and assisting in staving off infectuon is known as
Correct Answer
D. The fibrous capsule
Explanation
The fibrous capsule is the correct answer because it is the innermost connective tissue layer that protects the kidney and helps to prevent infection. It acts as a barrier against pathogens and provides structural support to the kidney. The perirenal fat capsule is the layer of fat that surrounds the fibrous capsule and provides additional protection and insulation. The renal fascia is a layer of connective tissue that anchors the kidney to surrounding structures. The hilum is a concave area on the kidney where blood vessels, nerves, and the ureter enter and exit. The renal medulla is the inner region of the kidney where urine is formed.
47.
The fenestrated endothelium of the capillary has pores small enough to exclude blood cells from the filtrate
Correct Answer
A. True
Explanation
The fenestrated endothelium of the capillary refers to the presence of small pores in the endothelial cells that line the capillary walls. These pores are small enough to prevent blood cells from entering the filtrate. This means that only small molecules and substances can pass through the capillary walls and enter the filtrate, while larger blood cells are excluded. Therefore, the statement is true.
48.
Chloride homeostasis is regulated as a side effect of sodium homeostasis
Correct Answer
A. True
Explanation
The statement is true because chloride homeostasis is closely linked to sodium homeostasis. Sodium and chloride ions are often found together in the body and they have a reciprocal relationship. When sodium levels increase, chloride levels also tend to increase, and vice versa. This is because both ions are regulated by similar mechanisms in the body, such as the kidneys' ability to reabsorb or excrete these ions. Therefore, maintaining sodium homeostasis also helps regulate chloride levels in the body.