Approximately 80% of the energy used for active transport is devoted to the reabsorption of __________.
What is the juxtaglomerular apparatus?
a system that regulates the rate of filtrate formation and systemic blood pressure
Most solutes that are reabsorbed in the proximal convoluted tubule use which of the following pathways?
During reabsorption of water in the proximal convoluted tubule, what causes water to diffuse from the lumen into the interstitial space?
an increase in the osmolarity of the interstitium
The decreased intracellular concentration of sodium in tubular cells during active transport is caused by which of the following mechanisms?
the sodium-potassium ATPase pump in the basolateral membrane
The active transport of which ion out of proximal convoluted tubule cells causes the reabsorption of both water and solutes?
Which of the following transporters in the luminal membrane results in secretion?
What is the limiting factor for the reabsorption of most actively transported solutes in the proximal tubule?
number of transport carriers in the luminal membrane
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?
The myogenic mechanism of renal autoregulation primarily involves smooth muscle in which blood vessels?
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 through which mechanism?
A nonfasting 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
The __________ keeps the urethra closed when urine is not being passed from the bladder and prevents leaking between voiding.
internal urethral sphincter
Since most patients with renal failure produce little or no urine, hemodialysis often involves removal of water from the blood. However, side-effects may develop if too much fluid is removed from the blood. Which of the following is NOT one of the potential side-effects?
vasoconstriction of afferent arterioles
The frequency of cystitis in men is lower than in women because ______.
the male urethra is longer than the female urethra
T/F: The proximal convoluted tubule is the portion of the nephron that attaches to the collecting duct.
Which cells of the kidney are chemoreceptors that respond to changes in solute content of the filtrate?
macula densa cells
What is the most direct function of the juxtaglomerular apparatus?
help regulate blood pressure and the rate of blood filtration by the kidneys
Select the correct statement about the nephrons.
The parietal layer of the glomerular capsule is simple squamous epithelium.
The fatty tissue surrounding the kidneys is important because it ________.
stabilizes the position of the kidneys by holding them in their normal position
The glomerulus differs from other capillaries in the body in that it ________.
is drained by an efferent arteriole
T/F: The macula densa cells are chemoreceptors that respond to changes in the urea content of the filtrate.
T/F: Blood pressure in the renal glomerulus is lower than in most parts of the body in order to conserve body water.
T/F: Aldosterone is a hormone that causes the renal tubules to reclaim sodium ions from the filtrate.
T/F: 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
T/F: If the GFR is too low, needed substances may pass so quickly through the renal tubules that they are not absorbed and instead are lost in the urine.
Which of the choices below are the most important hormone regulators of electrolyte reabsorption and secretion?
angiotensin II and aldosterone
In the ascending limb of the loop of Henle the ________.
thick segment moves ions out into interstitial spaces for reabsorption
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
Reabsorption of high levels of glucose and amino acids in the filtrate is accomplished by ________.
secondary active transport
Which of the following is not true regarding tubular reabsorption?
It is a purely passive transport process
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
6. collecting duct
3, 6, 2, 1, 5, 4
A disease caused by inadequate secretion of antidiuretic hormone (ADH) by the pituitary gland with symptoms of polyuria is ________.
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
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
The mechanism that establishes the medullary osmotic gradient depends most on the permeability properties of the ________.
loop of Henle
If one says that the clearance value of glucose is zero, what does this mean?
Normally all the glucose is reabsorbed
An important characteristic of urine is its specific gravity or density, which is ________.
slightly higher than water (1.001-1.035)
T/F: The path urine takes after it is formed until it leaves the body is the urethra, urinary bladder, and finally the ureter
Polycystic kidney disease always affects both kidneys instead of only the right or left kidney because ______.
it is a genetic disease
Select the correct statement about urinary system development.
Kidneys develop from urogenital ridges
Fetal kidneys do not have to work very hard because
the placenta allows the mother's urinary system to clear the waste from fetal blood.
The body's water volume is closely tied to a powerful water "magnet." What magnet is referred to here?
T/F: Solutes, regardless of size, are able to move freely between compartments because water carries them along the osmotic gradients.
The most important force causing net water flow across capillary walls is ________.
hydrostatic pressure of capillary blood
Which of the following statements is true regarding fluid shifts?
Electrolytes have greater osmotic power than nonelectrolytes and therefore have the greatest ability to cause fluid shifts
The movement of fluids between cellular compartments ________.
is regulated by osmotic and hydrostatic forces
Which of the following describes the distribution of sodium and potassium between cells and body fluids?
K+ mainly in the cells, Na+ in the body fluids
Whereas sodium is found mainly in the extracellular fluid, most ________ is found in the intracellular fluid.
T/F: Water imbalance, in which output exceeds intake, causing an imbalance in body fluids, is termed dehydration.
T/F: It is impossible to overhydrate because people need as much water as they can drink to carry out ordinary body functions.
T/F: Dehydration can be caused by endocrine disturbances such as diabetes mellitus or diabetes insipidus.
One of the major physiological factors that triggers thirst is ________.
a rise in plasma osmolality
Which of the following hormones is important in stimulating water conservation in the kidneys?
T/F: Carotid artery and aortic baroreceptors are involved in long term adjustment to total body sodium ion content
T/F: The two hormones responsible for the regulation of calcium are pituitary hormone and calcitonin.
T/F: When aldosterone release is inhibited, sodium reabsorption cannot occur beyond the distal convoluted tubule.
Annie has just eaten a large order of heavily salted french fries, some pickled eggs, and some cheese. How will consuming this much salt affect her physiology?
There will be a temporary increase in blood volume
What hormone reduces blood pressure and blood volume by inhibiting nearly all events that promote vasoconstriction and sodium ion and water retention?
atrial natriuretic peptide
The single most important factor influencing potassium ion secretion is ________.
potassium ion concentration in blood plasma
Atrial natriuretic peptide is a hormone that is made in the atria of the heart. The influence of this hormone is to ________.
reduce blood pressure and blood volume by inhibiting sodium and water retention
T/F: Blood acidity results in depression of the CNS, whereas blood alkalosis results in overexcitement of the CNS.
T/F: As ventilation increases and more carbon dioxide is removed from the blood, the hydrogen ion concentration of the blood decreases
T/F: Weak acids are able to act as chemical buffering systems for the body because they partially dissociate
The maintenance of the proper pH of the body fluids may be the result of ________.
the control of respiratory ventilation
Problems with fluid, electrolyte, and acid-base balance are particularly common in infants because of their ________.
T/F: Hypoproteinemia reflects a condition of unusually high levels of plasma proteins and causes tissue edema.
Which of the following is not a disorder of water balance?
excessive hydration due to excess ANP secretion
Hypoproteinemia is a condition of unusually low levels of plasma proteins. This problem is often characterized by ________.
The term hypotonic hydration refers to ________.
a condition that may result from renal insufficiency or drinking extraordinary amounts of water
Which of the following conditions promotes edema?
T/F: Atrial natriuretic peptide reduces blood pressure and blood volume by inhibiting nearly all events that promote vasodilation and potassium and water retention.
Which of the following does NOT impact how much sodium is reabsorbed?
transport maximum of the renal proximal tubule
In order to buffer a strong acid into a weak acid, which has a less dramatic effect on pH, what chemical should be used as the buffer?