A&P 2 CH. 25 Urinary
If one says that the clearance value of glucose is zero, what does this mean?
100% of glucose is reabsorbed.
Place the following in correct sequence from the formation of a drop of urine to its elimination from the body. 1. major calyx 2. minor calyx 3. nephron 4. urethra 5. ureter 6. collecting duct
3, 6, 2, 1, 5, 4
Which of the following is the best explanation for why the cells of the proximal convoluted tubule (PCT) contain so many mitochondria?
A great deal of active transport takes place in the PCT.
Which of the hormones below is responsible for facultative water reabsorption?
ADH
The renal corpuscle is made up of ___
Bowman's capsule and glomerulus
Which of the following statements best describes the difference between the intrinsic and extrinsic controls of the kidney?
Extrinsic controls have the greatest effect on systemic blood pressure while intrinsic controls have a greater effect on GFR.
Which of the following does NOT describe the juxtaglomerular complex?
Its macula densa cells produce aldosterone.
If blood pressure drops very low (MAP is below 80mmHg) renin enzyme will be secreted by granular cells. Which of the following is NOT likely to occur?
Kidney perfusion will increase
What would happen if the capsular hydrostatic pressure were increased above normal?
Net filtration would decrease.
The relatively long half-life of lipid-soluble hormones (steroid hormones) compared to water-soluble hormones is due in part to the way that these hormones are passed into the filtrate from the glomerular capillaries. From the list below select the best explanation for why lipid-soluble (steroid) hormones have a relatively long half-life.
Steroid hormones travel in the plasma on large transport proteins that cannot pass through the filtration membrane.
Which of the following processes would be considered as a secretory rather than an excretory activity?
Sweat removal by the skin
If the glomerular mesangial cells contract, reducing the overall surface area of the glomerulus, which of the following is NOT likely to occur?
Systemic blood pressure will be lowered.
If the diameter of the efferent arterioles leading away from the glomerulus increases (vasodilation), which of the following is NOT likely to occur?
Systemic blood pressure will decrease
If the diameter of the afferent arterioles leading to the glomerulus decreases (vasoconstriction), which of the following is NOT likely to occur?
Systemic blood pressure will decrease.
If the diameter of the efferent arterioles leading away from the glomerulus decreases (vasoconstriction), which of the following is NOT likely to occur?
Systemic blood pressure will go up
If the diameter of the afferent arterioles leading to the glomerulus increases (vasodilation), which of the following is NOT likely to occur?
Systemic blood pressure will go up.
Which of the following is incorrect?
The concentration of urine is lower when urine volume is reduced.
The lab results of a newly admitted patient indicate renal impairment. How might this affect the dosing regimen of drugs that are excreted by the kidney?
The dosage or the dosage interval may need to be reduced.
The macula densa cells respond to ____
The macula densa cells respond to ____
Select the correct statement about the nephrons.
The parietal layer of the glomerular capsule is simple squamous epithelium
Hydrostatic pressure is the primary driving force of plasma through the filtration membrane into the capsular space. All but one of the following statements reflects why hydrostatic pressure is so high in the glomerular capillaries. Select the one statement that does NOT explain the high pressure within the glomerular capillaries.
The volume of plasma in the efferent arteriole is higher when compared to the afferent arteriole.
What is the best explanation for the microvilli on the apical surface of the proximal convoluted tubule (PCT)?
They increase the surface area and allow for a greater volume of filtrate components to be reabsorbed.
Which of the following is NOT associated with the renal corpuscle?
a vasa recta
The thin segment of the nephron loop's descending limb ____
aids in the passive movement of water out of the tubule
Which of the following hormones acting on the collecting duct is most responsible for retaining sodium ions in the blood?
aldosterone
Which of the choices below are the most important hormone regulators of electrolyte reabsorption and secretion?
angiotensin II and aldosterone
The ________ artery lies on the boundary between the cortex and medulla of the kidney.
arcuate
The kidneys are stimulated to produce renin ___
by a decrease in the blood pressure
Which of the choices below is NOT a method by which the cells of the renal tubules can raise blood pH?
by secreting sodium ions
What is the effect of antidiuretic hormone on the cells of the collecting duct?
causes aquaporins to be inserted into the apical membranes
The function of angiotensin II is to __
constrict arterioles and increase blood pressure
The descending limb of the nephron loop _____
contains fluid that becomes more concentrated as it moves down into the medulla
Which of the following is NOT reabsorbed by the proximal convoluted tubule?
creatinine
The presence of protein in the urine indicates which of the following?
damage to the filtration membrane
Upon reaching what point in the nephron is reabsorption (1) dependent upon the body's needs at the time and (2) regulated by hormones?
distal convoluted tubule
Which of the choices below is NOT a glomerular filtration rate control method?
electrolyte levels
Which of the choices below is NOT a function of the urinary system?
eliminates solid, undigested wastes and excretes carbon dioxide, water, salts, and heat
The glomerular capsular space contains ____
filtrate
Which of the choices below is a function of the nephron loop?
form a large volume of very dilute urine or a small volume of very concentrated urine
Glomerular filtration rate can be controlled by manipulating one major variable, which is ____
glomerular hydrostatic pressure
The factor that promotes filtrate formation at the glomerulus is the __
glomerular hydrostatic pressure
The chief force pushing water and solutes out of the blood across the filtration membrane is _
glomerular hydrostatic pressure (glomerular blood pressure)
Your patient's urinalysis shows a large amount of protein in the urine. This suggests a problem in the ______
glomerulus
What is the most direct function of the juxtaglomerular apparatus?
help regulate blood pressure and the rate of blood filtration by the kidneys
Excretion of dilute urine requires ____
impermeability of the collecting tubule to water
An increase in the permeability of the cells of the collecting tubule to water is due to a(n) _____
increase in the production of ADH
Cells and transport proteins are physically prevented from passing through the filtration membrane. This has the following effect on filtration.
increasing osmotic pressure in the glomerular capillaries that reduces the amount of filtration
Alcohol acts as a diuretic because it __
inhibits the release of ADH
The glomerulus differs from other capillaries in the body in that it _____
is drained by an efferent arteriole
Bulk flow of nutrients, ions and water into the peritubular capillaries is the result of all of the following except one. Select the answer below that does NOT describe a cause of bulk flow of fluids into the peritubular capillaries.
leaky tight junctions of peritubular capillary's endothelium
Reabsorption of nutrients like glucose and amino acids takes place in the proximal convoluted tubule (PCT) via cotransporters that utilize secondary active transport. Which of the following would stop the reabsorption of glucose at the apical surface of the cells in the PCT?
loss of Na+-K+ ATPase in the basolateral surface of PCT cells
Which of the choices below is the salt level-monitoring part of the nephron?
macula densa
The functional and structural unit of the kidneys is the ___
nephron
The mechanism that establishes the medullary osmotic gradient depends most on the permeability properties of the ___
nephron loop
The mechanism of water reabsorption by the renal tubules is ____
osmosis
The fluid in glomerular capsule is similar to plasma except that it does NOT contain a significant amount of ____
plasma protein
Which of the following is NOT a part of the juxtaglomerular complex?
podocyte cells
Except for potassium ions, tubular secretion of most unwanted substances occurs in the ____
proximal convoluted tubule
The filtration membrane includes all EXCEPT ___
renal fascia
Reabsorption of high levels of glucose and amino acids in the filtrate is accomplished by ___
secondary active transport
An important physical characteristic of urine is its specific gravity or density, which is ____
slightly higher than water
Approximately 80% of the energy used for active transport is devoted to the reabsorption of ______
sodium
The fatty tissue surrounding the kidneys is important because it ___
stabilizes the position of the kidneys by holding them in their normal position
In the ascending limb of the nephron loop the __
thick segment moves ions out into interstitial spaces for reabsorption