Approximately 80% of the energy used for active transport is devoted to the reabsorption of _____.
Sodium
What is the juxtaglomerular apparatus?
a system that regulates the rate of filtrate formation and systemic blood pressure
Which of the following substances is not normally found in
filtrate?
A) ions, such as sodium and potassium
B) blood
cells and large particles
C) nitrogenous waste particles, such as
urea
D) water and small solutes
B. Blood cells and large particles
What is the primary driving force that produces glomerular filtration?
hydrostatic pressure of blood (blood pressure)
Which substance would be found in higher concentration if the
membrane were damaged?
A) creatinine
B) glucose
C)
protein
D) chloride
C. Protein
If the osmotic pressure in the glomerular capillaries increased from 28 mm Hg to 35 mm Hg, would net filtration increase or decrease?
Decrease
Calculate the net filtration pressure if capillary hydrostatic pressure = 60 mm Hg, capillary osmotic pressure =25 mm Hg, and capsular hydrostatic pressure =10 mm Hg.
25 mm Hg
Which of the following best describes glomerular filtration rate
(GFR)?
A) the volume of urine leaving the kidneys per
minute
B) the volume of filtrate created by the kidneys per
minute
C) the volume of filtrate created at the glomerulus per
liter of blood flowing through the glomerular capillaries
D) the
volume of blood flowing through the glomerular capillaries per minute
B. the volume of filtrate created by the kidneys per minute
GFR regulation mechanisms primarily affect which of the
following?
A) glomerular hydrostatic pressure (HPg)
B) blood
osmotic pressure (OPg)
C) capsular hydrostatic pressure
(HPc)
D) capsular osmotic pressure (OPc)
A. glomerular hydrostatic pressure (HPg)
Macula densa cells of the juxtaglomerular apparatus (JGA) regulate GFR through which intrinsic mechanism?
tubuloglomerular feedback
The myogenic mechanism of renal autoregulation primarily involves smooth muscle in which blood vessels?
afferent arterioles
What does a high concentration of NaCl in the renal tubule at the juxtaglomerular apparatus (JGA) most likely indicate?
insufficient NaCl reabsorption due to high GFR
Through the tubuloglomerular feedback mechanism, how would an increase in filtrate NaCl concentration affect afferent arteriole diameter?
Afferent arteriole diameter would decrease.
Granular cells of the juxtaglomerular apparatus (JGA) regulate GFR indirectly through which mechanism?
renin-angiotensin mechanism
A non-fasting urine sample from an individual who has previously ingested donuts and a soft drink showed the presence of sugar (glucose). Which of the following statement explains the presence of the glucose in the urine?
The individual exceeded the transport maximum.
Which part of the brain controls the micturition reflex?
Pons
The frequency of cystitis in men is lower than in women because ______.
the male urethra is longer than the female urethra
Urinary incontinence may occur if a person has ______.
an overactive detrusor muscle
True or False
Urea is reabsorbed in the loop of Henle.
False
An increase in the permeability of the cells of the collecting tubule to water is due to ________.
an increase in the production of ADH
True or False
Aldosterone is a hormone that causes the renal tubules to reclaim sodium ions from the filtrate.
True
The kidneys are stimulated to produce renin ________.
by a decrease in the blood pressure
Which of the following is not reabsorbed by the proximal convoluted
tubule?
A) Na+
B) K+
C) Glucose
D) Creatinine
Creatinine
The renal ___________ is continuous with the ureter.
Pelvis
Which gland sits atop each kidney?
Adrenal
The juxtaglomerular apparatus is responsible for ______
regulating the rate of filtrate formation and controlling systemic blood pressure
True or False
The urethra contains an internal sphincter of smooth muscle.
True
True or False
The terminal portion of the urinary system is the urethra.
True
In response to increased levels of aldosterone, the kidneys produce ____________________.
Urine with a lower concentration of sodium ions
True or False
The ureter transports urine from the kidney to the urinary bladder.
True
The ability to concentrate urine depends on the functions of ____________________.
Loop of henle (or the collecting duct)
The glomerulus differs from other capillaries in the body in that it ________
is drained by an efferent arteriole
The descending limb of the loop of Henle contains ________.
fluid that becomes more concentrated as it moves down into the medulla
Urine passes through the ________.
pelvis of the kidney to ureter to bladder to urethra
Tubular reabsorption ________.
by active mechanisms usually involves movement against an electrical and/or chemical gradient
Urea transport into the medullary collecting duct is enhanced by ________.
ADH
True or False
Urine is 95% water by volume.
True
True or False
The ascending limb of the loop of Henle is impermeable to sodium chloride and actively transports water into the surrounding interstitial fluids.
False