Mastering A and P Urinary System
At a volume of __________ mL, there may be sufficient pressure in the bladder to force the opening of the internal urinary sphincter and, consequently, the external urinary sphincter.
500
The average pH for normal urine is about __________.
6.0
Net filtration pressure can be measured as __________.
A given carrier protein normally works equally well transporting in both directions.
Which of the following statements about the regulation of the glomerular filtration rate (GFR) is FALSE?
Constriction of the afferent arteriole increases the GFR.
The sympathetic division of the nervous system has which of the following effects on the kidney?
It causes a decrease in the GFR because of the constriction of the afferent arteriole.
Which of the following conditions does NOT occur as the urinary system ages?
Nephrons become more sensitive to ADH.
Which portion of the nephron contains cuboidal cells covered with microvilli?
PCT
The kidneys are __________.
each surrounded by a fibrous capsule, adipose, and renal fascia posterior to the spleen, stomach, and liver in a retroperitoneal location behind the parietal peritoneum
Dilation of the afferent arteriole and glomerular capillaries and constriction of the efferent arteriole when blood flow and glomerular pressure decline cause __________.
elevation of glomerular blood pressure to normal levels
Countercurrent refers to the __________.
exchange occurring between fluids moving in opposite directions
Which mechanism is important in the reabsorption of glucose and amino acids when their concentrations in the filtrate are relatively high?
facilitated transport
Which of the following statements concerning the nephron loop and its function is FALSE?
Sodium and chloride are pumped out of the thin descending limb of the nephron loop.
Sympathetic innervation of the afferent arterioles causes __________.
a decrease in GFR and slowing of filtrate production
The fibrous capsule is __________.
a layer of collagen fibers that covers the outer surface of each kidney
Aldosterone stimulates ion pumps along the distal convoluted tubule (DCT), the collecting tubule, and the collecting duct, causing __________.
a reduction in the number of sodium ions lost in the urine
The filtration process within the renal corpuscle involves passage across the filtration membrane, which consists of __________.
fenestrated capillary endothelium, dense layer, and filtration slits
Which of the following is NOT a function of the urinary system?
adaptive immunity
Cortical radiate arteries branch to form __________, which enter __________.
afferent arterioles; glomeruli
Which of the following is NOT reabsorbed in the nephron loop?
bicarbonate
ADH stimulates the reabsorption of water in __________.
both the distal convoluted tubule and the collecting system
The pressure that represents the resistance to flow along the nephron and conducting system is the __________.
capsular hydrostatic pressure (CHP)
What are the opposing forces of the filtration pressure at the glomerulus?
capsular hydrostatic pressure and blood osmotic pressure
Angiotensin II is a potent hormone that __________.
causes constriction of the efferent arteriole at the nephron stimulates secretion of aldosterone by the adrenal cortex and epinephrine by the adrenal medulla triggers the release of ADH in the CNS
Each of the following substances is secreted by the distal convoluted tubule (DCT) EXCEPT __________.
chloride ions
The thick segments in the nephron loop __________.
contain transport mechanisms that pump materials out of the filtrate
In which region of the kidney would you find the renal corpuscles?
cortex
To which vessels does blood flow immediately after it passes through the arcuate arteries?
cortical radiate arteries
What is the term for the type of transport where two substrates cross the membrane while bound to a carrier protein, with at least one following its concentration gradient?
cotransport
Inadequate ADH secretion results in the inability to reclaim the water entering the filtrate, causing __________.
dehydration
The functions of the urinary system include which of the following?
detoxifying poisons regulating ion concentrations stabilizing pH
What is the triple-layered muscle responsible for urinary bladder contractions?
detrusor
Which of the following disorders describes the production of very dilute urine as a result of a lack of ADH production?
diabetes insipidus
Autoregulation controls the glomerular filtration rate (GFR) by __________.
dilation of the afferent arteriole constriction of the efferent arteriole dilation of the glomerular capillaries
Sympathetic innervation into the kidney is responsible for __________.
direct stimulation of water and sodium ion reabsorption regulation of glomerular blood flow and pressure stimulation of renin release
What is the primary site for secretion of potassium and hydrogen ions into the filtrate?
distal convoluted tubule
Which portion of the renal segment is under ADH and aldosterone stimulation?
distal convoluted tubule
In which of the following parts of the nephron does aldosterone control the reabsorption of sodium ions?
distal convoluted tubule and collecting duct
What are the three concentric layers of connective tissue that protect and anchor the kidneys?
fibrous capsule, perinephric fat capsule, and renal fascia
Which of the following is NOT a waste product normally found in urine?
glucose
Which of the following is NOT found in normal urine?
glucose
When plasma glucose concentrations are higher than the renal threshold, glucose concentrations in the filtrate exceed the transport maximum (Tm), and __________.
glucose appears in the urine
Which of the following is NOT an effect of aging on the urinary system?
increased sensitivity to ADH
What is the result of the countercurrent multiplication mechanism?
increased solute concentration in the descending limb of the nephron loop
The collecting system in the kidney is responsible for __________.
making final adjustments to the sodium ion concentration and volume of urine
The inner layer of the kidney is the __________.
medulla
When antidiuretic hormone levels rise, the distal convoluted tubule becomes __________.
more permeable to water; water reabsorption increases
In which of the following areas of the nephron would countercurrent multiplication occur?
nephron loop
Which of the following parts of the nephron has two limbs with thick segments and thin segments?
nephron loop
What is the primary site in the nephron where the loss of water, sodium, and potassium ions is regulated?
nephron loop and collecting duct
Urine production begins in the __________.
nephrons
The difference between the net hydrostatic pressure and the net colloid osmotic pressure is the __________.
net filtration pressure
Which of the following is NOT a characteristic of carrier-mediated transport?
osmosis
Reabsorption and secretion at the kidneys involve __________.
osmosis diffusion carrier-mediated transport
During the micturition reflex, increased afferent fiber activity in the pelvic nerves facilitates __________.
parasympathetic motor neurons in the sacral spinal cord
Blood supply to the proximal and distal convoluted tubules of the nephron is provided by the __________.
peritubular capillaries
Juxtaglomerular nephrons __________.
produce concentrated urine
The renal papilla __________.
projects into the renal sinus
In a nephron, the long tubular passageway through which the filtrate passes includes the __________.
proximal and distal convoluted tubules and the nephron loop
In which of the following areas of the nephron are most nutrients reabsorbed?
proximal convoluted tubule
Sixty to 70 percent of the water is reabsorbed in the __________.
proximal convoluted tubule
What is the primary site of nutrient reabsorption in the nephron?
proximal convoluted tubule
Which portion of the nephron reabsorbs most of the important nutrients, such as glucose and amino acids as well as any plasma proteins?
proximal convoluted tubule (PCT)
Aldosterone __________ in the proximal convoluted tubule.
regulates potassium and sodium exchange
The functions of the urinary system include all of the following EXCEPT __________.
regulating body temperature
Which of the following brings oxygenated blood into the kidney?
renal artery
In which region would you find interlobar arteries?
renal column
The filtration of plasma that generates approximately 80 liters/day of filtrate occurs in the __________.
renal corpuscle
The glomerulus and the glomerular capsule form the __________.
renal corpuscle
Which of the following is a dense fibrous layer that anchors the kidney to surrounding structures?
renal fascia
In what part of the kidney are the renal pyramids located?
renal medulla
The region of the kidney containing the renal pyramids, renal columns, and interlobar arteries is called the __________.
renal medulla
What is the expanded, funnel-shaped structure in the kidney leading to the ureter?
renal pelvis
The segments of the nephron distal to the renal corpuscle are responsible for __________.
secretion of waste materials reabsorption of useful organic substrates reabsorption of over 90 percent of water from the tubule
The high osmotic concentrations found in the kidney medulla are primarily caused by the presence of __________.
sodium ions, chloride ions, and urea
Because of the small diameter of the glomerular capillaries, the blood pressure in the efferent arteriole is __________ that of the pressure in the afferent arteriole.
the difference between the net hydrostatic pressure and the blood colloid osmotic pressure
The renal corpuscle consists of __________.
the glomerular capsule and the glomerulus
Which of the following causes urinary incontinence?
the loss of muscle tone in the urinary sphincter muscles
The capillaries surrounding the nephron loop are called __________.
the vasa recta
The ureters are lined by what kind of epithelium, which allows them to be stretched when undergoing peristalsis and moving urine?
transitional
The mucosa of the urinary bladder consists of __________.
transitional epithelium
The collecting system __________.
transports fluid to the renal pelvis and adjusts the concentration and composition of urine
The area in the urinary bladder that is bounded by the openings of the ureters and the entrance to the urethra is the __________.
trigone
The openings of the urethra and the two ureters mark an area on the internal surface of the urinary bladder called the __________.
trigone
Which of the following organic wastes is generated from the catabolism of amino acids?
urea
What is the urinary structure that carries urine from the kidney to the urinary bladder?
ureter
Contraction of the muscular bladder forces the urine out of the body through the __________.
urethra
Which organ in the urinary system temporarily stores urine?
urinary bladder
The renal corpuscle consists of the __________.
glomerulus and glomerular capsule
Which of the following statements is FALSE?
Active secretion occurs primarily in the collecting duct.
Which of the following statements about the hilum of the kidney is FALSE?
It is the site of the adrenal glands.
Which of the following statements concerning the micturition reflex is FALSE?
The micturition reflex is controlled by neurons in the lumbar region of the spinal cord.
In which of the basic processes involved in urine formation does blood pressure force water and solutes across the wall of the glomerular capillaries?
filtration
What is the initial factor that determines whether urine will be produced?
filtration
In countercurrent multiplication, the countercurrent refers to the fact that an exchange occurs between __________.
fluids moving in opposite directions
The thin segments in the nephron loop are __________.
freely permeable to water and relatively impermeable to ions and other solutes
The amount of filtrate the kidneys produce each minute is the __________.
glomerular filtration rate
What is the outward pressure forcing water and solute molecules across the glomerulus wall?
glomerular hydrostatic pressure
Which of the following is the term for the blood pressure in the capillaries of the renal corpuscle?
glomerular hydrostatic pressure
A histological examination of the nephron would reveal simple squamous tissue __________.
in the nephron loop
The fluid in the ascending limb of the nephron loop moves __________ the fluid in the descending limb.
in the opposite direction of
Which of the following is NOT an effect of advanced age on the urinary system?
increase in the GFR
During periods of strenuous exercise, sympathetic activation causes the blood flow to __________.
increase to the skin and skeletal muscles and decrease to the kidneys
What results from the effect of aldosterone along the DCT, the collecting tubule, and the collecting duct?
increased conservation of sodium ions and water
Which of the following is NOT a function of the urinary system?
introduction of plasma proteins into blood plasma
To regulate pH, all of the following are secreted into the fluid in the collecting system EXCEPT __________.
iron
Which organ in the urinary system produces urine?
kidney
After passage through the nephron loop, the filtrate is __________.
less concentrated
Which of the following systems is NOT used to excrete wastes from the body?
lymphatic system
Kidney stones, or calculi, can be formed by deposits of __________.
magnesium salts uric acid calcium