Chapter 20 Urinary System Questions and Answers
Marvin goes on vacation to Maine and for a week eats nothing but seafood. The next week, he experiences intense pain in his big toe. He probably has
Gout
The ureter extends downward
behind the parietal peritoneum and joins the urinary bladder from below.
Results in a more dilute urine:
- drinking a large volume of water on a day when you rested and stayed inside
- overdosing on Losartan, a drug that blocks the action of angiotensin II
- a new virus that attacks and damages the pituitary gland
Results in a more concentrated urine:
- working outside on a hot day without access to drinking water
- over-expression of aquaporins
- overproduction of aldosterone
- increasing the permeability of the collecting duct to water
Label the parts of the urinary system and associated structures.
Secretion of atrial natriuretic peptide
increases sodium excretion.
In which of the following regions of the nephron is water actively transported?
None of the above
The micturition reflex center is in the
sacral segments of the spinal cord.
As a result of very low arterial blood pressure, glomerular hydrostatic pressure
drops and filtration decreases.
Kidney shrinkage with age is due to
loss of glomeruli.
The relative concentration of potassium is
higher in urine than plasma or glomerular filtrate.
Most hydrogen ions are secreted
actively into the entire renal tubule.
Part of the nephron:
- proximal convoluted tubules
- distal convoluted tubules
- renal corpuscles
- nephron loops
Renal vasculature:
- afferent arterioles
- renal arteries and veins
- efferent arterioles
- peritubular capillaries
The ________ is the tube that conveys urine outside the body.
urethra
Describe the composition of glomerular filtrate.
Like plasma, but lacking larger protein molecules.
The renal corpuscle consists of a capillary bed called the _____________ and a capsule of epithelial cells.
glomerulus
The __________________________ of blood forces water and solutes out of the blood and into the capsule.
hydrostatic pressure
Glomerular filtrate collects in the ________________________ before entering the first portion of the renal tubule, called the _____________ .
capsular space; proximal tubule
After flowing through the proximal tubule, fluid enters the ______________ which extends toward the renal papilla.
nephron loop
Fluid in the __________________ would flow into a collecting duct.
distal tubule
Which of the following indicates the parts of a renal tubule in the correct sequence from beginning to end?
Proximal convoluted tubule, descending limb of nephron loop, ascending limb of nephron loop, distal convoluted tubule
Label the blood vessels associated with the urinary system.
Causes increased GFR:
- increased blood levels of natriuretic peptide
- vasoconstriction of efferent arteriole (with no change to afferent arteriole)
- activity of angiotensin II
- excess body fluid volume
Causes decreased GFR:
- vasoconstriction of afferent arteriole (with no change to efferent arteriole)
- decreased sodium in ascending limb
Kidney stones are least likely to be composed of
cholesterol.
Which of the following is correct concerning the location of the kidneys?
They are located behind the parietal peritoneum.
What hormone is secreted by the kidneys?
erythropoietin
Recall the definition of ________________ : the maintenance of a stable internal environment. The function of the kidneys is important in maintaining the internal environment.
homeostasis
As water volume in the blood decreases and the osmolarity increases, the hormone _____ is released, causing the kidneys to retain water.
ADH
As sodium levels of the blood decrease, the hormone _________________ is released. It causes an increase in sodium reabsorption by the distal convoluted tubule and collecting duct.
aldosterone
As blood pH decreases, the secretion of _______________ by the renal tubules increases, producing a more acidic urine.
hydrogen ions
Overall, the kidneys are able to handle each component independently. Those that are too abundant in the blood are _________ and those whose levels are dropping are _________________.
excreted; reabsorbed
A renal clearance test determines the rate at which the kidneys can
remove a particular substance from the blood.
An increase in urine volume is termed
diuresis
Which of the following would increase the rate of glomerular filtration?
Increased blood pressure
An increase in glomerular osmotic pressure ________ the rate of glomerular filtration.
decreases
The renal medulla is composed of _____, whereas the renal cortex is composed of _____.
renal pyramids; renal corpuscles
Which of the following is a normal constituent of urine?
Urea
Water
Creatinine
Filtration of fluids and solutes from plasma
Glomerulus
Receives the plasma filtrate
Glomerular capsule
Reabsorption of nutrients, glucose, various ions, and water
Proximal convoluted tubule
Reabsorption of only water
Descending limb of nephron loop
Selective reabsorption of sodium, potassium and chloride ions
Ascending limb of nephron loop
Reabsorption of sodium, water, and secretion of hydrogen and potassium ions
Distal convoluted tubule
Place the name of each compound in the correct location to illustrate the steps in the activation of the renin-angiotensin system.
Define incontinence.
uncontrolled leakage of urine
Label the structures seen in the photomicrograph of the kidney.
Water channels in cell membranes formed by __________ are a result of ADH signaling in the kidneys.
aquaporins
When plasma glucose concentration exceeds the renal plasma threshold,
glucose appears in the urine.
Increases urine volume:
- taking a diuretic
- developing diabetes
- drinking a large volume of water during a day when you rested and stayed inside
Decreases urine volume:
- increasing the permeability of the collecting duct to water
- overexpression of aquaporins in collecting ducts
- working outside on a hot day without access to drinking water
Renal secretion occurs as:
substances pass from the peritubular capillaries to the nephron tubules.
All substances filtered from the blood by the nephron are excreted in the urine.
False
Reabsorption in the kidney occurs when:
substances pass from renal tubules to the peritubular capillaries.
What is the definition of renal filtration?
Fluid leaves the glomerulus and enters the Bowman's (glomerular) capsule.
The layers of a ureter are
outer fibrous coat, middle muscular coat, inner mucous coat.
A nephron consists of
a renal corpuscle and a renal tubule.
Place the sequence of events describing proximal convoluted tubule reabsorption in the correct order.
Athletes might abuse which of the following chemicals made in the urinary system to improve performance by increasing red blood cell production?
Erythropoietin (EPO)
Podocytes and pedicels are part of the
glomerular capsule.
The organs of the urinary system are
paired kidneys, paired ureters, a bladder and a urethra.
The first capillary bed associated with the nephron
filters
The urinary system is involved in the regulation of:
- bile secretion
- blood glucose levels
Place the labels in order, following the flow of blood through the kidney.
renal artery
interlobar artery
arcuate artery
cortical radiate artery
afferent arteriole
glomerular capillaries
efferent arterioles
peritubular capillaries
cortical radiate vein
arcuate vein
interlobar vein
renal vein
The _______________ is the layer that contains the capillary beds that function to filter the blood, called _______________. Most renal tubules are located in this layer.
renal cortex; glomeruli
The _________________ is the layer that contains the descending and ascending limbs of the ______________ that function in water and sodium reabsorption.
renal medulla; nephron loop
The ____________ is the hollow portion of the kidney, filled with vessels, the renal calyces, and the renal pelvis.
renal sinus
Label the pressures involved in determining the net filtration rate at a glomerulus using the hints provided. Note that the length of the arrows is relative to the value of each pressure.
Label the structures of the renal corpuscle and juxtaglomerular apparatus.
Indicate whether each of the following substances is reabsorbed from the filtrate or secreted into the filtrate.
Renal function that is associated with urine production:
- filtration of blood
- removal of nitrogenous wastes
- reduction of blood acidity
- blood pressure regulation
- blood volume regulation
Renal function that is NOT associated with urine production:
- secreting the enzyme renin
- activation of vitamin D
- release of erythropoitein
A renal corpuscle is a _____, whereas a renal tubule is a _____.
cluster of blood capillaries and glomerular capsule; highly coiled tubule exiting the glomerular capsule
When the urinary bladder becomes stretched, there is an increase in the frequency of action potentials traveling from:
the urinary bladder to the sacral region of the spinal cord.
In response to activation of the micturition reflex, ______ stimulate the smooth muscle on the urinary bladder to contract.
parasympathetic neurons
When urination is desired, decreased action potentials along which nerve pathway causes relaxation of the external urinary(urethral) sphincter?
somatic motor neurons from the spinal cord
If urination is not convenient, the brain sends impulses down the spinal cord to inhibit the micturition reflex.
true
Increases Filtration:
- increase in blood pressure
- constriction of efferent arteriole
Decreases filtration:
- increase in capsular pressure
- increase in plasma protein concentration
- obstruction in the proximal tubule
Nephron loop:
- countercurrent multiplier
- permeable only to water on the descending limb
- active transport of sodium out of the ascending limb
- increases the sodium gradient of the kidney medulla
Vasa Recta:
- functions to provide oxygen to the kidney cells
- functions to provide nutrients to the kidney cells
- freely permeable to water and Na+ throughout structure
- provides blood supply without altering the osmotic gradient of the renal medulla
Urea is a byproduct of the metabolism of
amino acids
Uric acid is a byproduct of the metabolism of
nucleic acids
Creatinine is a byproduct of the metabolism of
creatine
If glucose is not reabsorbed in the tubular fluid ___________ increases.
the osmotic pressure
The ______________ acts as the countercurrent multiplier.
nephron loop
The increase in osmolarity as filtrate moves down the descending limb is due to ________ moving out of the tubule.
water
The decrease in osmolarity of the filtrate as it moves up the ascending limb is due to ___________ moving out of the tubule.
solutes
The filtrate is ______________ at the tip of the nephron loop and _________________ at the end of the ascending limb.
hypertonic; hypotonic
The concentration gradient found in the renal tubules is also found in the interstital fluid of the renal ______________.
medulla
Nocturnal enuresis is
bedwetting
Name the blood vessel that delivers blood to each glomerulus.
afferent arteriole
The hormone ADH promotes water reabsorption through the wall(s) of the
distal convoluted tubule and collecting duct.
When sodium ions are reabsorbed through the wall of the renal tubule by active transport, chloride ions are
reabsorbed by passive transport.
Place the structures of the urinary tract in order, following the flow of urine.
The micturition reflex can be voluntarily controlled by the
relaxation of the external urethral sphincter.
Extracorporeal shock-wave lithotripsy is used to treat
kidney stones