44 terms

Chapter 20

The kidneys are located retroperitoneally. This means they are _____ the peritoneum
Name the blood vessel that delivers blood to each glomerulus
afferent arteriole
Name the renal process that occurs at the renal corpuscle
Describe the composition of glomerular filtrate.
Like plasma, but lacking larger protein molecules
A greater amount of filtration occurs at glomeruli than at other capillary beds of the body because:
glomeruli have a higher hydrostatic pressure.
Vasoconstriction of the afferent arteriole and/or vasodilation of the efferent arteriole will cause a(n) _____ in GFR
At rest, approximately ______ percent of blood plasma passing through the glomeruli is filtered.
Water reabsorption from the proximal convoluted tubule is closely linked to the active reabsorption of:
sodium ions
Hydrogen ions are _____ all along the length of the renal tubule
The external urinary sphincter is ____ muscle
Glomerular filtration rate (GFR) ______ with aging
Define incontinence
uncontrolled leakage of urine
Which of the following is not a function of the kidneys?
Synthesis of plasma proteins
The organs of the urinary system are
paired kidneys, paired ureters, a bladder and a urethra
Athletes might abuse which of the following chemicals made in the urinary system to improve performance by increasing red blood cell production?
Erythropoietin (EPO)
Which of the following is correct concerning the location of the kidneys?
They are located behind the parietal peritoneum
A renal corpuscle includes the
glomerulus and glomerular capsule
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
A nephron consists of
a renal corpuscle and a renal tubule
A biochemical important in glomerulus formation in the embryo is
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
The first capillary bed associated with the nephron
Once in the glomerular capsule, the filtrate moves into the
renal tubule
The reabsorption of glucose occurs primarily through the walls of the
proximal convoluted tubule.
When plasma glucose concentration exceeds the renal plasma threshold
glucose appears in the urine.
When sodium ions are reabsorbed through the wall of the renal tubule by active transport, chloride ions are
reabsorbed by passive transport
The countercurrent mechanism functions primarily in the
nephron loop
Most hydrogen ions are secreted
actively into the entire renal tubule.
Which of the following would increase the rate of glomerular filtration?
Increased blood pressure
In which of the following regions of the nephron is water actively transported?
None of the above
Which of the following is a normal constituent of urine?
All of the above
Which choice describes the countercurrent mechanism of the nephron loop?
Water moves out of the descending limb; sodium moves out of the ascending limb
Barbara has the disease gout. The inflammation and pain in her joints is due to excess _____________ in her plasma, which leads to crystal deposits in her great toe joint.
uric acid
As a result of very low arterial blood pressure, glomerular hydrostatic pressure
drops and filtration decreases
Aldosterone from the adrenal cortex causes sodium ions to be
conserved and potassium ions to be excreted
Michael is 26 years old. He becomes dehydrated after a long run if he has not drunk enough. His infant son Sean, however, becomes dehydrated fairly frequently. This difference in susceptibility to dehydration is because
infant kidneys are less able to conserve water
A renal clearance test determines the rate at which the kidneys can
remove a particular substance from the blood
An increase in glomerular osmotic pressure ________ the rate of glomerular filtration
Filtration rate in the glomerulus is increased by
both vasodilation of the afferent arteriole and vasoconstriction of the efferent arteriole
The juxtaglomerular apparatus regulates the filtration rate by _____.
renin-angiotensin II vasoconstricting both the afferent and efferent arterioles
An adaptation of the epithelial cells of the proximal convoluted tubule for reabsorption is
microscopic projections called microvilli
A decrease in the glomerular capsule hydrostatic pressure will _____ the rate of glomerular filtration
The composition of glomerular filtrate differs from that of plasma by including
the same substances as plasma except for larger protein molecules
Glomerular filtration produces about ________ liters of fluid in twenty-four hours