Where in the nephron does most solute reabsorption occur?
proximal convoluted tubule
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?
Which hormone(s) is/are required for facultative water reabsorption in the collecting ducts?
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
Which part of the brain controls the micturition reflex?
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
Urinary incontinence may occur if a person has ______.
an overactive detrusor muscle
T/F: Having a kinked ureter is called renal ptosis.
T/F: The proximal convoluted tubule is the portion of the nephron that attaches to the collecting duct.
T/F: The entire responsibility for urine formation lies with the nephron.
Which cells of the kidney are chemoreceptors that respond to changes in solute content of the filtrate?
macula densa cells
Which of the choices below is the salt level-monitoring part of the nephron?
What is the most direct function of the juxtaglomerular apparatus?
help regulate blood pressure and the rate of blood filtration by the kidneys
Which of the following is not a part of the juxtaglomerular apparatus?
Select the correct statement about the nephrons.
The parietal layer of the glomerular capsule is simple squamous epithelium.
The macula densa cells respond to ________.
changes in solute content of the filtrate
The filtration membrane includes all except ________.
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
The ________ artery lies on the boundary between the cortex and medulla of the kidney.
Which of the following is the most likely to cause pyelonephritis?
infection of the urinary bladder
Hydronephrosis may be caused by all EXCEPT which of the following?
T/F: The macula densa cells are chemoreceptors that respond to changes in the urea content of the filtrate.
T/F: Atrial naturetic peptide inhibits sodium reabsorption.
T/F: Tubular secretion is effective in controlling blood pH.
T/F: An excessive urine output is called anuria.
T/F: The myogenic mechanism reflects the tendency of vascular smooth muscle to stretch.
T/F: Urea is reabsorbed in the loop of Henle.
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: The collecting duct is impermeable to water in the presence of ADH.
T/F: Glomerular filtration is an ATP-driven process.
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
Which of the hormones below is responsible for facultative water reabsorption?
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
Excretion of dilute urine requires ________.
impermeability of the collecting tubule to water
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 ________.
Alcohol acts as a diuretic because it ________.
inhibits the release of ADH
Which of the following is not reabsorbed by the proximal convoluted tubule?
The mechanism of water reabsorption by the renal tubules 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
T/F: Blood in the urine may be a symptom of bladder cancer.
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
T/F: Fetal kidneys have the primary responsibility of clearing wastes from the fetal blood.
Polycystic kidney disease always affects both kidneys instead of only the right or left kidney because ______.
it is a genetic disease
T/F: Incontinence is the inability to control voluntary micturition
T/F: The urethra contains an internal sphincter of smooth muscle.
T/F: The act of emptying the bladder is called voiding.
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.
Under normal circumstances, most water is lost in __________.
The role of ADH is to __________.
increase water reabsorption
The body's water volume is closely tied to a powerful water "magnet." What magnet is referred to here?
Which of the following is NOT a hormone involved in water and electrolyte balance?
Which hormone raises blood calcium levels?
Which buffer system is the most abundant in the body?
What is the effect of hyperventilation on pH?
Which age group most commonly has fluid, electrolyte, and acid-base balance issues?
T/F: Solutes, regardless of size, are able to move freely between compartments because water carries them along the osmotic gradients.
T/F: Electrolytes determine most of the chemical and physical reactions of body fluids.
T/F: The most abundant cation in intracellular fluid is sodium.
T/F: Adipose tissue is one of the most hydrated of all tissues in the human body.
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: Thirst is always a reliable indicator of body water need.
T/F: To remain properly hydrated, water intake must equal water output.
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.
T/F: The thirst center in the brain is located in the hypothalamus
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: Hypercalcemia causes muscle tetany.
T/F: Premenstrual edema may be due to enhanced reabsorption of sodium chloride.
T/F: The main way the kidney regulates potassium ions is to excrete them.
T/F: Aldosterone stimulates the reabsorption of sodium while enhancing potassium secretion.
T/F: When aldosterone release is inhibited, sodium reabsorption cannot occur beyond the distal convoluted tubule.
The regulation of potassium balance ________.
involves aldosterone-induced secretion of potassium
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
Which of the choices below exerts primary control over sodium levels in the body?
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: Prolonged hyperventilation can cause alkalosis.
T/F: Respiratory acidosis results when lungs are obstructed and gas exchange is inefficient.
T/F: As ventilation increases and more carbon dioxide is removed from the blood, the hydrogen ion concentration of the blood decreases
T/F: The phosphate buffer system is relatively unimportant for buffering blood plasma.
T/F: Weak acids are able to act as chemical buffering systems for the body because they partially dissociate
T/F: The normal pH of blood is 7.35-7.45.
T/F: Most acidic substances (hydrogen ions) originate as by-products of cellular metabolism.
The maintenance of the proper pH of the body fluids may be the result of ________.
the control of respiratory ventilation
Which of the following is not a chemical buffer system?
Respiratory acidosis can occur when ________.
a person's breathing is shallow due to obstruction
Problems with fluid, electrolyte, and acid-base balance are particularly common in infants because of their ________.
What is the most abundant intracellular cation?
T/F: Hypoproteinemia reflects a condition of unusually high levels of plasma proteins and causes tissue edema.
What is the driving force for water intake?
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?
What receptors does the brain use to detect changes in osmolality?
How much water is generated per day from cellular metabolism?
T/F: Atrial natriuretic peptide reduces blood pressure and blood volume by inhibiting nearly all events that promote vasodilation and potassium and water retention.
T/F: Aldosterone is secreted in response to low extracellular potassium.
Which of the following does NOT impact how much sodium is reabsorbed?
transport maximum of the renal proximal tubule
What is the most important trigger for aldosterone release?
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?
Which of the following creates the greatest osmotic pressure?