the region that combines several minor calyces to form two or three major calyces?
The minor and major calyces collect urine and distribute it onward through the urinary tract.
What two structures constitute the renal corpuscle?
glomerulus and glomerular (Bowman's) capsule
Which part of the renal tubule is lined with cuboidal epithelial cells bordered by dense microvilli?
proximal convoluted tubule
In which kidney region are all renal corpuscles located?
renal cortex
Where does the efferent arteriole of the juxtamedullary nephron carry blood to?
vasa recta
Which capillary bed produces filtrate?
glomerulus
What is the function of the macula densa cells of the juxtaglomerular complex (JGC)?
monitoring the NaCl content of the filtrate
The __________ collect(s) urine, which drains continuously from the papillae; the urine is then emptied into the __________.
calyces; renal pelvis
What is the juxtaglomerular complex?
a system that regulates the rate of filtrate formation and systemic blood pressure
The glomerulus differs from other capillaries in the body in that it ________.
is drained by an efferent arteriole
Which of the following does not describe the juxtaglomerular complex?
Its macula densa cells produce aldosterone.
describe the juxtaglomerular complex
It regulates the rate of filtrate formation.
It helps control systemic blood pressure.
Its granular cells produce renin.
The filtration membrane includes all except ________.
renal fascia
The position of the kidneys behind the peritoneal lining of the abdominal cavity is described by the term retroperitoneal.
true
The proximal convoluted tubule is the portion of the nephron that attaches to the collecting duct.
false
Which of the following substances is not normally found in filtrate?
blood cells and large particles
substances found in filtrate
water and small solutes
ions, such as sodium and potassium
nitrogenous waste particles, such as urea
What is the primary driving force (pressure) that produces glomerular filtration?
hydrostatic pressure of blood (blood pressure)
Which substance would be found in higher concentration if the membrane were damaged?
protein
If the osmotic pressure in the glomerular capillaries increased from 28 mm Hg to 35 mm Hg, would net filtration increase or decrease?
net filtration would decrease
Calculate the net filtration pressure if capillary hydrostatic pressure is 60 mm Hg, capillary osmotic pressure is 25 mm Hg, and capsular hydrostatic pressure is 10 mm Hg.
25 mm Hg
Which of the following statements about ADH (antidiuretic hormone) is correct?
ADH is released by the posterior pituitary gland.
What is the osmolarity of the filtrate at the end of the proximal tubule?
isotonic – 300 mOsm
In overhydration, what would be the levels of ADH (high, normal, or low) and what would be the osmolarity of the urine?
ADH – low; 100 mOsm (urine)
In severe dehydration or blood loss, what would be the levels of ADH and what would be the urine flow rate?
ADH – high; low urine flow rate (0.25 ml/min)
Which of the following best describes glomerular filtration rate (GFR)?
the volume of filtrate created by the kidneys per minute
GFR regulation mechanisms primarily affect which of the following?
glomerular hydrostatic pressure (HPg)
Which of the following are mechanisms of intrinsic control of glomerular filtration (renal autoregulation)?
myogenic mechanism and tubuloglomerular feedback
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
What is the chief force pushing water and solutes out of the blood and across the filtration membrane of the glomerulus?
hydrostatic pressure in glomerular capillaries (HPgc)
Where does antidiuretic hormone (ADH) exert its effects to promote water reabsorption?
collecting duct
Where in the nephron does most solute reabsorption occur?
proximal convoluted tubule
Capsular hydrostatic pressure is the chief force pushing water and solutes out of the blood and across the filtration membrane.
false
The ascending limb of the loop of Henle is permeable to water
false
The __________ is a skeletal muscle under conscious control that allows urine to leave the bladder.
external urethral sphincter
Which of the following is NOT one of the things that must happen for micturition to occur?
The extrusor muscle must relax.
things that must happen for micturition to occur?
The external urethral sphincter must open.
The detrusor muscle must contract.
The internal urethral sphincter must open.
Which of the following is NOT a cause of anuria?
vasodilation of afferent arterioles
causes of anuria
renal failure
obstruction in the urethra
vasodilation of afferent arterioles
heart failure
The kidneys are stimulated to produce renin ________.
by a decrease in the blood pressure
Place the following in correct sequence from the formation of a drop of urine to its elimination from the body.
nephron -> collecting duct -> minor calyx -> major calyx -> ureter -> urethra
Reabsorption of high levels of glucose and amino acids in the filtrate is accomplished by ________.
secondary active transport
If the Tm for a particular amino acid is 120 mg/100 ml and the concentration of that amino acid in the blood is 230 mg/100 ml, the amino acid will ________.
appear in the urine
Excretion of dilute urine requires ________.
impermeability of the collecting tubule to water
In the ascending limb of the loop of Henle the ________.
thick segment moves ions out into interstitial spaces for reabsorption
In the kidneys, the countercurrent mechanism involves the interaction between the flow of filtrate through the loop of Henle of the juxtamedullary nephrons (the countercurrent multiplier) and the flow of blood through the limbs of adjacent blood vessels (the countercurrent exchanger). This relationship establishes and maintains an osmotic gradient extending from the cortex through the depths of the medulla that allows the kidneys to vary urine concentration dramatically.
true
Water reabsorption through the proximal convoluted tubule is termed obligatory water reabsorption, whereas water reabsorption through the distal convoluted tubule is termed facultative water reabsorption.
true
Glomerular filtration is an ATP-driven process.
false
In the absence of hormones, the distal tubule and collecting ducts are relatively impermeable to water.
true
Aldosterone is a hormone that causes the renal tubules to reclaim sodium ions from the filtrate.
true
An excessive urine output is called anuria.
false
Tubular secretion is effective in controlling blood pH.
true
Approximately 80% of the energy used for active transport is devoted to the reabsorption of __________.
sodium
Under normal conditions, the proximal convoluted tubule (PCT) reabsorbs all of the glucose, lactate, and amino acids in the filtrate and 65% of the Na+ and water.
true
Which urinary structure serves as the transporter for urine toward the bladder?
ureter
The path urine takes after it is formed until it leaves the body is the urethra, urinary bladder, and finally the ureter.
false
The urinary bladder is composed of ________ epithelium.
transitional
The act of emptying the bladder is called voiding.
true