Ch. 31 - Patho EAQ

Which findings in the urinalysis would be normal? Select all that apply. a. Absence of glucose b. Presence of acidic urine c. Presence of cloudy urine d. Absence of ketone bodies e. Dark orange-colored urine

a. Absence of glucose b. Presence of acidic urine d. Absence of ketone bodies Rationale Absence of glucose, presence of acidic urine, and absence of ketone bodies are all normal findings. Normal urine does not show the presence of glucose and is acidic in nature. Normal urine does not have ketone bodies. Cloudy urine indicates the presence of purulent matter in urine, which is not normal. Dark orange color indicates the presence of bilirubin and is not normal.

Which term would describe the chambers that receive urine from the collecting ducts and form the entry into the renal pelvis? a. Calyces b. Renal fascia c. Macula densa d. Renal pyramids

a. Calyces Rationale The calyces are chambers that receive urine from the collecting ducts and form the entry into the renal pelvis, an extension of the upper ureter. The renal capsule and fatty layer are covered with a double layer of renal fascia, fibrosis tissue. Macula densa is located between the afferent and efferent arterioles and consists of sodium-sensing cells. The renal pyramids are located in the medulla and contain the loops of Henle and collecting ducts.

Which term would describe the elimination of a substance in the final urine? a. Excretion b. Tubular secretion c. Glomerular filtration d. Tubular reabsorption

a. Excretion Rationale Excretion is the elimination of a substance in the final urine. Tubular secretion is the transfer of substances from the plasma of the peritubular capillary to the tubular lumen. Glomerular filtration is the movement of fluid and solutes across the glomerular capillary membrane and into the Bowman space. Tubular reabsorption is the movement of fluids and solutes from the tubular lumen into the peritubular capillary plasma.

Which term would describe the part of the kidney that is the entry and exit for renal blood vessels, nerves, lymphatic vessels, and ureter? a. Hilum b. Cortex c. Medulla d. Calyces

a. Hilum Rationale The hilum is a medial indentation that serves as the entry and exit for the renal blood vessels, nerves, lymphatic vessels, and ureter. The cortex is the outer layer of the kidney; the medulla forms the inner part of the kidney; and the calyces are chambers that receive urine from the collecting ducts.

Which changes would be the effects of aging on renal function? Select all that apply. a. Loss of renal mass b. Increased thirst sensation c. Impaired renal blood flow d. Increased glucose reabsorption e. Delayed response to acid-base changes

a. Loss of renal mass c. Impaired renal blood flow e. Delayed response to acid-base changes Rationale Loss of renal mass, impaired renal blood flow, and delayed response to acid-base changes are all effects of aging on renal function. Aging causes loss of renal mass because structural changes occur in the kidney. Aging causes impairment of renal blood flow and alters sodium and water balance. Aging causes a delayed response to acid-base changes. Aging causes decreased (not increased) thirst sensation, and diminished water intake may alter water balance. Aging causes a decrease (not increase) in glucose reabsorption.

Which information would be true regarding the urethra? a. The entire urethra is lined with mucus-secreting glands. b. The external urethral sphincter is under involuntary control. c. The internal urethral sphincter is composed of striated muscle. d. The urethra extends from the superior side of the bladder.

a. The entire urethra is lined with mucus-secreting glands. Rationale The entire urethra is lined with mucus-secreting glands. The external urethral sphincter is under voluntary control, not involuntary; the internal sphincter is under involuntary control. A ring of smooth muscle (not striated) forms the internal urethral sphincter at the junction of the urethra and bladder. The urethra extends from the inferior side (not superior) side of the bladder to the outside of the body.

Which hormone synthesized by the kidney would cause vasodilation and natriuretic and diuretic effects? a. Urodilatin b. Vitamin D c. Erythropoietin d. Antidiuretic hormone

a. Urodilatin Rationale Urodilatin is a natriuretic peptide secreted by the distal convoluted tubules and collecting ducts that causes vasodilation and natriuretic and diuretic effects. Vitamin D is a hormone that can be obtained in the diet or synthesized by the action of ultraviolet radiation on the cholesterol present in the skin; it does not cause vasodilation or natriuretic/diuretic effects. Vitamin D is necessary for the absorption of calcium and phosphate by the small intestine. Erythropoietin stimulates the bone marrow to produce red blood cells in response to tissue hypoxia; it does not cause vasodilation or natriuretic/diuretic effects. The concentration of the final urine is controlled by antidiuretic hormone, which is secreted from the posterior pituitary or neurohypophysis. It increases water permeability and reabsorption; it does not cause vasodilation or natriuretic/diuretic effects.

Which structure composed of sodium-sensing cells would be located between the afferent and efferent arterioles? a. Podocytes b. Macula densa c. Juxtaglomerular cells d. Juxtaglomerular apparatus

b. Macula densa Rationale Between the afferent and efferent arterioles is the macula densa (sodium-sensing cells) of the distal tubule. The podocytes are specialized cells of the epithelium from which pedicles (projections) radiate and adhere to the basement membrane. Juxtaglomerular cells release renin as a result of the information gained by the macula densa. The juxtaglomerular apparatus is composed of the juxtaglomerular cells, mesangial cells, and the macula densa cells.

Which process would be the primary function of the proximal tubule? a. Dilutes urine b. Reabsorbs sodium c. Produces uromodulin d. Filters plasma at the glomerulus

b. Reabsorbs sodium Rationale Active reabsorption of sodium is the primary function of the proximal tubule. Urine concentration or dilution occurs principally in the loop of Henle, distal tubules, and collecting ducts, not the proximal tubule. Another important function of the loop of Henle is the production of uromodulin; it is not the function of the proximal tubule. The glomerular filtration membrane, not the proximal tubule, filters blood components and plasma at the glomerulus.

Which cause would be expected if the urinalysis shows increased levels of urobilinogen? a. Hyperglycemia b. Red blood cell hemolysis c. Dysfunction of glomerulus d. Increase in fat metabolism

b. Red blood cell hemolysis Rationale Presence of increased levels of urobilinogen in the urine indicates red blood cell hemolysis. Hyperglycemia is anticipated if the glucose levels are increased. Dysfunction of glomerulus is anticipated if protein levels are increased. Increase in fat metabolism is anticipated if ketones are increased.

Which vessel will supply blood to the lower, middle, and upper thirds of the kidney? a. Renal veins b. Renal arteries c. Interlobar arteries d. Glomerular capillaries

b. Renal arteries Rationale The renal arteries supply blood to the lower, middle, and upper thirds of the kidney. The renal veins follow the arterial path in reverse direction (take blood away) and have the same names as the corresponding arteries; they eventually empty into the inferior vena cava. The interlobar arteries are lobar subdivisions that travel down renal columns and between pyramids, forming afferent glomerular arteries. The glomerular capillaries consist of four to eight vessels arranged in a fistlike structure from the afferent arteriole and empty into the efferent arteriole.

Which renal structure would drain urine directly into the ureter? a. Urethra b. Renal pelvis c. Collecting duct d. Proximal tubule

b. Renal pelvis Rationale The renal pelvis drains urine directly into the ureter and is an extension of the upper ureter. The urethra drains urine out of the body, not into the ureter. The collecting duct drains urine into the minor calyx, not the ureter. The proximal tubule drains urine into the loop of Henle, not the ureter.

When glomerulotubular balance dysfunctions, which substances would be primarily affected? Select all that apply. a. Vitamin D b. Sodium c. Glucose d. Calcium e. Water

b. Sodium e. Water Rationale Glomerulotubular balance prevents wide fluctuations in the excretion of sodium and water into the urine. Vitamin D, glucose, and calcium are not affected.

Which rationale would explain the reason infants need smaller dosages of medications? a. Infants have an increased ability to efficiently remove excess water and solutes. b. The decreased ability to efficiently remove solutes results in increased toxicity risks. c. There is a decreased risk for metabolic acidosis related to excreting acid and retaining bicarbonate. d. Infants have longer loops of Henle, which decrease concentrating ability, and a more dilute urine results.

b. The decreased ability to efficiently remove solutes results in increased toxicity risks. Rationale The kidney's decreased ability to efficiently remove solutes in the infant results in increased toxicity risks. Newborns have a decreased, not increased, ability to efficiently remove excess water and solutes. There is an increased, not decreased, risk for metabolic acidosis because the mechanisms for excreting acid and retaining bicarbonate are maturing. Infants have shorter, not longer, loops of Henle and a decreased ability to concentrate urine.

Which process would the antidiuretic hormone (ADH) stimulate? a. Urine excretion b. Water reabsorption c. Sodium reabsorption d. Hydrogen ion excretion

b. Water reabsorption Rationale The presence of ADH makes the renal tubules more permeable to water, which enhances water reabsorption. ADH causes urine excretion to decrease; it does not stimulate this process. ADH does not affect sodium reabsorption in the kidneys; sodium is controlled by aldosterone. ADH does not affect hydrogen excretion; distal tubules determine the amount of hydrogen lost depending on acid-base balance.

Which measurement (in milliliters) would be the amount of blood the kidneys receive per minute? a. 500 b. 875 c. 1200 d. 2000

c. 1200 Rationale The kidneys are vascular organs and receive 1000 mL to 1200 mL of blood per minute, or about 20% to 25% of the cardiac output. Values of 500 and 875 are too low, and 2000 is too high.

Which physiologic mechanism would normally keep urine from moving back toward the kidneys when the bladder contracts? a. Constriction of the prostate gland b. Constriction of the renal papillae c. Compression of the distal end of the ureters d. Compression of the proximal end of the urethra

c. Compression of the distal end of the ureters Rationale Contraction of the bladder during micturition (urination) compresses the distal end of the ureter, preventing reflux. Constriction of the prostate gland does not prevent urine from moving back toward the kidneys; however, prostate enlargement would reduce the flow of urine to the outside of the body in males. Constriction of the renal papillae does not keep urine from moving back toward the kidney; the renal papillae are projections of the papillary ducts into the calyces and are located above the ureters. The single urethra drains urine from the bladder to the outside of the body; compression of the proximal end would not keep urine from moving back toward the kidneys.

Which renal structure would be the primary site for plasma filtration? a. Tubule b. Podocyte c. Glomerulus d. Slit membrane

c. Glomerulus Rationale The glomerulus is the site for filtering plasma. The tubule is where filtrate is sent after the glomerulus to reabsorb and secrete substances as needed; it is the plasma filtration site. The epithelium has specialized cells called podocytes from which pedicles (projections) radiate and adhere to the basement membrane, but it is not the primary site for plasma filtration. Pedicles from adjacent podocytes interlock, forming an elaborate network of intercellular clefts called filtration slits or slit membranes; they are not the primary site for plasma filtration.

Which mechanism would normally occur to restore a decreased blood calcium level? a. There is an increased absorption of calcium in the stomach. b. Vitamin D 3 stimulates the pituitary gland to release calcium. c. Parathyroid hormone stimulates renal calcium reabsorption. d. An increased intake of milk products will increase calcium absorption.

c. Parathyroid hormone stimulates renal calcium reabsorption. Rationale A decreased plasma calcium level stimulates the secretion of parathyroid hormone, causing renal calcium reabsorption. Parathyroid hormone then stimulates a sequence of events that helps restore plasma calcium toward normal levels. Calcium is absorbed in the intestine, not the stomach. While vitamin D 3 is needed to increase calcium, the pituitary gland does not release calcium. Increased intake of milk products may not increase calcium absorption.

Which type of cells would comprise the macula densa? a. Protein-filtering b. Renin-releasing c. Sodium-sensing d. Hydrogen-secreting

c. Sodium-sensing Rationale Between the afferent and efferent arterioles is the macula densa, a tissue comprising the sodium-sensing cells of the distal tubule. There are no protein-filtering cells in the kidney; normally, all the protein is reabsorbed. A group of specialized cells known as juxtaglomerular cells (renin-releasing cells) are located around the afferent arteriole where it enters the glomerulus. The distal tubules (not the macula densa) help regulate hydrogen.

Which explanation would be accurate in describing the anemia of chronic renal failure? a. The anemia is from a deficiency of 1,25-dihydroxy-vitamin D 3 synthesis. b. The multiple diuretics required for treatment inhibit the formation of red blood cells. c. The kidney fails to produce erythropoietin, which stimulates bone marrow to produce red blood cells. d. High levels of circulating calcium bind with phosphate and prevent the formation of red blood cells.

c. The kidney fails to produce erythropoietin, which stimulates bone marrow to produce red blood cells. Rationale The anemia of chronic renal failure can be related to the lack of erythropoietin. The kidneys produce the hormone erythropoietin, which stimulates the bone marrow to produce red blood cells. Decreased oxygen levels trigger the kidney into production of erythropoietin. However, in chronic renal failure, the kidneys have been damaged and are not able to produce erythropoietin, resulting in anemia of chronic renal failure. In chronic renal failure there is a lack of 1,25-dihydroxy-vitamin D 3 synthesis, which affects calcium and phosphate levels; it does not produce anemia of chronic renal failure. Diuretics do not affect the formation of red blood cells or loss of blood, leading to anemia of chronic renal failure. Calcium does affect phosphate levels, but this does not cause anemia of chronic renal failure; this process affects bone formation and function.

Which characteristic would be typical regarding the renal system? a. The mesangial cells are a type of nephron in the kidney. b. The renal corpuscle is the juxtaglomerular apparatus in the kidney. c. The right kidney is slightly lower than the left because of the overlying liver. d. The kidney is covered with a double layer of renal fascia, which is then covered by a layer of fat.

c. The right kidney is slightly lower than the left because of the overlying liver. Rationale Because of the overlying liver, the right kidney is slightly lower than the left. The mesangial cells have phagocytic ability similar to that of monocytes; they release inflammatory cytokines and can contract to regulate glomerular capillary blood flow but are not a type of nephron. The renal corpuscle is composed of the glomerulus, mesangial cells, Bowman space, and Bowman capsule; the juxtaglomerular apparatus comprises the juxtaglomerular cells and the macula densa cells. The kidney is covered with a layer of fat, then a double layer of renal fascia.

Which finding would be abnormal from the following urinalysis report: Turbidity cloudy; Specific gravity 1.015; Glucose negative; and pH 7.0? a. pH b. Glucose level c. Turbidity d. Specific gravity

c. Turbidity Rationale Turbidity is abnormal. Turbidity should be clear; purulent matter will make the turbidity cloudy. A normal pH is 4.6 to 8.0, so pH is normal (7.0). Glucose should normally be negative. Specific gravity is normally 1.010 to 1.025, so specific gravity is normal (1.015).

If the posterior pituitary is damaged, which hormone would be affected? a. Renin b. Aldosterone c. Erythropoietin d. Antidiuretic hormone

d. Antidiuretic hormone Rationale The posterior pituitary secretes antidiuretic hormone. The kidney's juxtaglomerular apparatus (juxtaglomerular cells, macula densa cells, and mesangial cells) secretes renin. The adrenal cortex (not the posterior pituitary) secretes aldosterone. The juxtamedullary cortex (not the posterior pituitary) in the kidneys secretes erythropoietin.

Which hormone would be increased when the blood volume and blood pressure increase? a. Aldosterone b. Angiotensin I c. Angiotensin II d. Atrial natriuretic peptide

d. Atrial natriuretic peptide Rationale Atrial natriuretic peptide is released in response to elevated blood volume and blood pressure and acts to increase water and sodium excretion to decrease blood volume and blood pressure. Aldosterone and angiotensin I and II would decrease (not increase) in response to elevated blood volume and pressure.

Which hormone would stimulate the production of red blood cells in the bone marrow? a. Renin b. Creatinine c. Aldosterone d. Erythropoietin

d. Erythropoietin Rationale Erythropoietin produced by the kidneys in response to hypoxia stimulates the bone marrow to increase its production of red blood cells. Renin does not stimulate the bone marrow to produce red blood cells but causes the generation of angiotensin. Creatinine is not a hormone but is a metabolic waste product of skeletal muscle metabolism. Aldosterone does not stimulate the bone marrow to produce red blood cells but causes sodium to be reabsorbed.

Which nephron will extend deep into the medulla? a. Kidney b. Cortical c. Midcortical d. Juxtamedullary

d. Juxtamedullary Rationale The juxtamedullary nephrons lie close to and extend deep into the medulla (about 40 mm). The kidney contains the nephrons. Cortical nephrons extend partially into the medulla, not deep. Midcortical nephrons have short or long loops.

Which process would be the primary function of the kidney? a. Promotes storage of urine b. Inhibits cell and tissue metabolism c. Increases waste metabolic products d. Maintains a stable internal environment

d. Maintains a stable internal environment Rationale The primary function of the kidney is to maintain a stable internal environment for optimal cell and tissue metabolism. The bladder stores urine, not the kidneys. The kidney does not inhibit cell and tissue metabolism. The kidneys excrete metabolic waste products, not increase them.

Which intrinsic mechanism would allow renal blood flow and glomerular filtration rate (GFR) to stay relatively constant? a. Detrusor b. Micturition c. Filtration fraction d. Renal autoregulation

d. Renal autoregulation Rationale Renal blood flow and GFR are relatively constant, a relationship maintained by an intrinsic autoregulatory mechanism, renal autoregulation. The purpose of autoregulation of blood flow is to prevent large changes in GFR when there are increases or decreases in systemic blood pressure. The detrusor is the smooth muscle coat of the bladder; it does not help renal blood flow and GFR stay constant. Micturition is urination, not an intrinsic mechanism to allow renal blood flow and GFR to stay relatively constant. The ratio of glomerular filtrate to renal plasma flow per minute (120/600 = 0.20) is called the filtration fraction; this does not help consistency in renal blood flow and GFR.

Which information regarding the kidneys would be included in a teaching session? a. They are between the level of the fifth and tenth thoracic ribs. b. They are located near the top of the vertebral column. c. The left kidney is positioned slightly lower than the right kidney. d. The kidneys are protected by both strong back muscles and fat.

d. The kidneys are protected by both strong back muscles and fat. Rationale The kidneys are protected by strong back muscles and fat. They are located on either side of the vertebral column between the twelfth thoracic vertebra and the third lumbar vertebra, not between the level of the fifth and tenth thoracic ribs. The kidneys are not located near the top of the vertebral column. The right kidney is lower than the left kidney, not vice versa.

Which structure will allow the body to eliminate urine? a. Ureter b. Kidney c. Bladder d. Urethra

d. Urethra Rationale Urine is released from the bladder through the urethra. The ureters funnel urine to the bladder. The kidney makes the urine. The bladder stores the urine that it receives from the kidney by way of the ureters.