Renal, Digestive, & Nutrition A&P II
How are proteins transported from the tubule lumen into the peritubular capillaries?
Transported by pinocytosis across the luminal membrane and digested into amino acids
True or False: A positive feedback mechanism called countercurrent multiplier involves the nephron loop, producing a concentration of tubule solution by moving water into the interstitial space.
True
True or False: All inulin filtered by the glomerulus remains in the renal tubule and appears in the urine.
True
True or False: Calcium is a substance that is regulated by reabsorption.
True
True or False: Due to the sodium-potassium pump, most potassium in the body is found in the intracellular fluid.
True
True or False: During hemorrhage, blood pressure drops. This is one possible stimulus for angiotensin II formation.
True
True or False: In the proximal tubules, sodium is actively transported out of the filtrate, and water follows by osmosis
True
True or False: Most of the reabsorption of glomerular filtrate occurs in the proximal tubules and descending limbs of nephron loops.
True
True or False: Renal clearance is the volume of blood plasma from which a particular waste is completely removed in one minute. True
True
True or False: Salt is actively transported across the membrane of the ascending loop of Henle, into the interstitial fluid
True
True or False: The magnesium ion is a major electrolyte in the body.
True
What are some examples of substances eliminated by the kidneys?
Urea Glucose Uric acid Creatinine
Promotes a Decrease in Blood Pressure
Vasodilation declining levels of ADH decreased sodium reabsorption
What are the names of the characteristics usually associated with urine?
Volume pH Color Smell
All that contributes to the function of the countercurrent multiplier.
Water is reabsorbed across the descending limb of the nephron loop. Water moving out of the descending limb increases the salt concentration in the tubular fluid that flows into the ascending limb of the nephron loop. Concentration of water increases in the loop lumen as the fluid moves through the nephron loop.
The micturition reflex can be voluntarily controlled by the
cerebral cortex stimulating or inhibiting the external urethral sphincter.
Fluid retention ________ urine output.
decrease
During _____________, water loss is greater than the loss of solutes, creating a hypertonic blood plasma.
dehydration
Salt _______ pass through the membrane of the descending limb.
does not
A fluid imbalance occurs when fluid output ____________ fluid intake
does not equal
Carbonic acid dissociates into a bicarbonate ion and hydrogen ion, therefore it is a(n)
electrolyte
An individual's conscious decision to urinate is due to altering nerve signals relayed from the cerebral cortex through the spinal cord and along the pudendal nerve to cause relaxation of the
external urethral sphincter.
Lactic acid is an example of a ____________ acid.
fixed
During exercise, dehydration will cause a net movement of water
from intracellular fluid to extracellular fluid.
Osmolarity-detecting cells located in nuclei of the __________ become stimulated by an increasing blood solute concentration.
hypothalamus
The net result of angiotensin II, aldosterone, and ADH cooperatively is a(n) ________ in blood pressure resulting largely from increased blood volume.
increase
The net result of angiotensin II, aldosterone, and ADH cooperatively is a(n) _________ in blood pressure resulting largely from increased blood volume.
increase
Edema is an example of fluid sequestration in which fluid accumulates in the _________ around cells, and is characterized by puffiness or swelling.
interstitial space
The phosphate buffering system is found in
intracellular fluid
Glomerular filtration rate (GFR) is typically measured using the filtering rate of a polysaccharide fiber called
inulin.
Fixed acids from body cells include
ketoacids
After puberty, females have a higher body fat percentage compared to males of the same age. Therefore, the percentage of body fluid in females will generally be ___________ compared to males.
lower
The ________________ ion participates in hundreds of enzymatic reactions, and is the second most abundant cation in the intracellular fluid.
magnesium
As salt leaves the tubular fluid in the ascending limb, the interstitial fluid becomes ________ concentrated
more
At the renal threshold for glucose,
more glucose is in the filtrate than active transport can handle.
Molecules that do not dissociate (or come apart) are called
nonelectrolytes
Urine that is always formed, regardless of the hydration state of the body, is an example of __________ water loss.
obligatory
Water passes through the membrane of the descending limb and into the interstitial fluid through
osmosis
Antidiuretic hormone provides a means of controlling water
output
A person who experiences higher than normal levels of phosphate in their blood and higher than normal levels of Ca²⁺ in their urine probably suffers from a deficiency in the production of
parathyroid hormone.
The countercurrent multiplier system is an example of
positive feedback
The increased osmolarity of the blood stimulates the hypothalamus to stimulate the _______ pituitary to release ADH.
posterior
The increased osmolarity of the blood stimulates the hypothalamus to stimulate the _________ pituitary to release ADH.
posterior
Aldosterone is a steroid hormone that is transported within the blood plasma and eventually binds to receptors within _______ of the kidney.
principle cells
The majority of glucose is reabsorbed through the walls of the
proximal convoluted tubule.
ADH will work on the kidneys to _________ water into the bloodstream.
reabsorb
If renal plasma clearance is a test to measure the volume of a substance that can be completely cleared in 1 minute, and if the GFR of urea is 125 mL/min, and renal plasma clearance of urea is 70 mL/min, that means the remainder of the urea is
reabsorbed
Aldosterone's binding to these cells causes increased _________ and retention of both Na⁺ and water, and increased secretion and then excretion of K⁺.
reabsorption
Carbonic acid is
regulated by the respiratory system.
Because equal amounts of Na⁺ and water are reabsorbed, blood osmolarity
remains constant.
The maximum plasma concentration of a substance that can be carried in the blood without eventually appearing in the urine is called the
renal threshold.
Atrial natriuretic peptide inhibits the release of
renin
Low blood pressure causes the kidneys to increase the secretion of _____ from the JG cells.
renin
Low blood pressure causes the kidneys to increase the secretion of ________ from the JG cells.
renin
Relaxation of the external urethral sphincter is caused by
signals from the brain
Aldosterone acts on the DCT of the kidney tubules to reabsorb greater amounts of _______ from the tubular fluid.
sodium
During dehydration blood volume declines and _______ concentration rises.
sodium
During dehydration blood volume declines and _________ concentration rises.
sodium
The external urethral sphincter is under ___________ control.
somatic
The cell type in the distal tubule and collecting duct that is responsible for Na⁺ and water reabsorption is
the principal cell
A product of the metabolism of certain nucleic acid bases is
uric acid.
A negative feedback system is used until the blood ______ and osmolarity return to normal levels.
volume
Antidiuretic hormone provides a means of controlling _______ output
water
Aldosterone acts on the _________ of the kidney tubules to reabsorb greater amounts of sodium from the tubular fluid.
DCT
What causes an increase in the frequency of action potentials from the bladder to the spinal cord?
Distension of the bladder from an increase in urine
Promotes an Increase in Blood Pressure
Increased release of renin vasoconstriction increased activity of ACE increasing levels of aldosterone
All that will stimulate angiotensin II formation.
Low blood pressure High blood pressure
Which substances are secreted into the filtrate?
NH4-, Drugs, and H+
Aldosterone increases the number of _________ and Na⁺ channels, so more Na⁺ is reabsorbed from the filtrate back into the blood.
Na⁺/K⁺ pumps
The micturition reflex involves impulses from the bladder traveling to which region of the spinal cord?
Sacral
What occurs when there is an increase in aldosterone secretion in response to an increase in renin by the juxtaglomerular apparatus.
Sodium secretion increases. Potassium secretion increases. Sodium reabsorption increases. Potassium reabsorption increases.
Transport proteins in the basolateral and luminal membranes control the movement of substances using which of the following cellular processes?
Tertiary transport mechanisms Osmosis Primary and secondary active transport
All that are true regarding potassium balance.
The intracellular fluid serves as a reservoir for potassium. When pH is low, potassium leaves the ICF and enters the ECF.
What are some examples of drugs, hormones, or large substances eliminated by the kidneys?
Human chorionic gonadotropin (hCG) Penicillin
The kidneys help regulate blood pH by excreting ___________in the urine and by reabsorbing _____________.
H+; bicarbonate
With GFR = UV/P, concentration of inulin in urine = 125 mg/mL; volume of urine = 1 mL/min; and concentration of inulin in plasma = 1 mg/mL, then GFR =
125 mL/min.
As a part of the urea recycling process, in order for the concentration gradient to be maintained, it is important that urea makes up about _______ of the solutes of the interstitial fluid concentration gradient.
50%
The release of ______ directly stimulates the collecting ducts of the kidney to increase water reabsorption from the tubular filtrate.
ADH
The release of __________ directly stimulates the collecting ducts of the kidney to increase water reabsorption from the tubular filtrate.
ADH
Causes Water Retention
ADH hypersecretion Renin release Ingestion of water Increased osmolarity of blood
All the hormones that increase fluid output.
Aldosterone ANP
Causes Water Loss
Aldosterone hyposecretion Decreased renal tubular reaborption of water Hemorrhage
Water occupies two main fluid compartments within the body, the intracellular fluid compartment and the extracellular fluid compartment. Which of the following statements is true concerning the volume of intracellular fluid?
Approximately two-thirds of the water is in the intracellular fluid compartment.
True or False: A patient who secretes too much antiduretic hormone may be in danger of low blood pressure.
False
True or False: Inulin is freely filtered by the juxtaglomerular apparatus.
False
True or False: Since aldosterone increases retention of sodium, blood osmolarity is increased as a result.
False
True or False: Specific gravity is the density of a substance compared to the density of mineral oil.
False
True or False: Sympathetic impulses cause the smooth muscle of the bladder wall to contract.
False
True or False: The active transport of salt in the descending limb is responsible for the increase in concentration of tubular fluid.
False
True or False: The female urethra serves to transport urine and unfertilized eggs to the exterior of the body.
False
If the transport maximum (Tm) of glucose is 320 mg/minute, what will happen if the tubular fluid contains 350 mg/minute of glucose?
Glucose will be excreted into the urine.
Which substances are reabsorbed from the filtrate?
Glucose, water, Mg2+, HCO3-, Amino acids, Vitamins.
Sodium exits the ascending limb and enters the interstitial fluid through
active transport
The hormone _________ acts in this part of the nephron and has a big impact on sodium and potassium levels in the filtrate.
aldosterone
The activation of ________ stimulates widespread vasoconstriction, release of ADH from the posterior pituitary, as well as the adrenal cortex, to release aldosterone.
angiotensin II
The activation of _________ stimulates widespread vasoconstriction, release of ADH from the posterior pituitary, as well as the adrenal cortex to release aldosterone.
angiotensin II
Overconsumption of alcohol can cause the hypothalamus to sense that the blood is too dilute, resulting in a decrease in the production of _______ thus reducing the reabsorption of water leading to dehydration.
antidiuretic hormone
When the level of the hormone ___________ increases, a person will experience an increase in Na⁺ excretion in their urine.
atrial natriuretic peptide
n the bicarbonate buffering system, carbonic acid buffers a strong base to produce
bicarbonate
The most important chemical buffering system in the extracellular fluid is the
bicarbonate buffering system.
