Test 4 - Unit 6 & 7 Flashcards
If clearance of a substance is greater than GFR, the substance is ______.
Net secreted by the kidney
If a substance was net reabsorbed by the kidney, the plasma clearance would be lower than GFR.
If a substance is only filtered, then the clearance would equal GFR.
The renal corpuscle is the site where __________.
- glucose reabsorption occurs
- plasma is filtered from the glomerulus into Bowman’s capsule
- sodium ions are reabsorbed
- the steep medullary osmotic gradient is established
Plasma is filtered from the glomerulus into Bowman’s capsule
Glucose reabsorption from the renal filtrate is due to __________.
- osmosis and simple diffusion along the distal tubule
- Sequential active transport and facilitated diffusion by the cells of the proximal tubule
- Osmotic pressure in the golmerular capillaries
- Active transport along the descending loop of Henle
Sequential active transport and facilitated diffusion by the cells of the proximal tubule
Which of the following would not result in an increase in GFR?
- increased glomerular pressure
- increased resistance in the efferent arteriole
- increased resistance in the afferent arteriole
- relaxation of mesangial cells
increased resistance in the afferent arteriole
Poisoning the Na-K-ATPase in the proximal tubule would likely __________.
decrease the amount of glucose reabsorption in this segment
In kidney renal tubules, all of the following substances normally are excreted into urine as it forms except __________.
- potassium ions
- glucose
- hydrogen ions
glucose
As long as an individual has a normal plasma glucose concentration, 100% of the glucose in the filtrate is reabsorbed. However, potassium and hydrogen ions are excreted in the urine in order to regulate blood pH and plasma potassium concentrations. The hydrogen ions are secreted from the proximal and distal convoluted tubule as well as the collecting duct. Potassium ions are secreted from the distal convoluted tubule and the collecting duct.
In and around the urinary bladder, skeletal muscle can be found in the __________.
- external urethral sphincter
- internal urethral sphincter
- detrusor muscle
- ureters
External urethral sphincter
Urine is carried from the collecting duct to what structure?
- renal pelvis
- loop of henle
- ureter
- urethra
Renal pelvis
The nephron is the functional unit of the kidney because __________.
- the nephron consists of vascular parts and tubular parts
- there are a million nephrons per kidney
- the nephron is essentially continuous with the external environment
- the nephron filters the plasma, reabsorbs critical molecules, and excretes the rest
the nephron filters the plasma, reabsorbs critical molecules, and excretes the rest
Which part of the nephron always has low permeability to water, regardless of hormone levels?
- collecting duct
- proximal tubule
- ascending loop of henle
- descending loop of henle
Ascending loop of henle
Secretion differs from filtration in that __________.
secretion is selective because it is carrier-mediated
Factors that favor filtration at the glomerulus include ________
- the concentration of proteins in the bowman’s space
- capillary blood pressure and the concentration of proteins in the bowman’s capsule
- capillary blood pressure
- concentration of proteins in the plasma
- capillary blood pressure and the concentration of proteins in the plasma
capillary blood pressure and the concentration of proteins in the bowman’s capsule
Tubular reabsorption __________.
permits reclamation of filtered items from the plasma, occurs in the loop of Henle, and is responsible for the movement of amino acids, CA2+, Cl- and water at the proximal convoluted tubule
In a normal kidney in a healthy individual, glucose __________.
- is freely filtered at the glomerulus
- is excreted in the urine
- moves by simple diffusion across the membranes of the proximal tubule
- is actively transported in the distal tubule
is freely filtered at the glomerulus
Where is renal filtrate formed in the kidney’s outer shell, which is also called the
renal cortex
The ability of the nephron to filter substances based on size and charge is not due to the __________.
- capillary endothelium
- basla lamina
- epithelium of the bowman’s capsule
- hydrostatic pressure
hydrostatic pressure
If a person with a normal body fluid osmolarity drinks a large quantity of water, which of the following would occur if the kidneys could not excrete any of the water?
- Decreased plasma osmolarity
- Cell shrinkage
- Hypervolemia and cell shrinkage
- Hypervolemia
- Hypervolemia and decreased plasma osmolarity
Hypervolemia and decreased plasma osmolarity
An ACE (angiotensin converting enzyme) inhibitor would be used to treat __________.
- Hypertension since ACE inhibition will result in decreased secretion of anti-diuretic hormone and aldosterone
- Hypertension since ACE inhibition will decrease the rate of urine production
- Hypotension since ACE inhibition will result in increased secretion of anti-diuretic hormone and aldosterone
- Hypotension since ACE inhibition will decrease the rate of glomerular filtration
Hypertension since ACE inhibition will result in decreased secretion of anti-diuretic hormone and aldosterone
People suffering from central diabetes insipidus (a disorder of the hypothalamus or pituitary gland) may have increased __________.
- Urine volume
- Urine osmolarity
- Plasma osmolarity
- Plasma osmolarity and urine volume
- Urine volume and ADH levels
- ADH levels
Plasma osmolarity and urine volume
The effects of ANG II on the central nervous system
- Increase activity of the respiratory control center
- Increase thirst, increase cardiac output, and cause peripheral vasoconstriction
- Inhibit secretion of ADH from the posterior pituitary gland
- Act on the medulla oblongata to decrease blood pressure
Increase thirst, increase cardiac output, and cause peripheral vasoconstriction
A vasopressin receptor antagonist would __________.
- Cause vasoconstriction and increased blood pressure
- Prevent membrane recycling in collecting duct cells
- Increase peripheral resistance
- Cause aquaporins to be inserted into the apical membranes of collecting duct cells
Prevent membrane recycling in collecting duct cells
The organ(s) that regulate water loss to maintain water balance is (are) the
- Lungs, skin, and kidneys
- Kidneys
- Lungs, and kidneys
- Liver
- Lungs
- Skin
Kidneys
The signals controlling ADH release come from _______.
- The macula densa
- Osmoreceptors in the hypothalamus
- Arterial baroreceptors
- All answers are correct
All answers
Moderate changes in blood pressure (mean arterial pressure not less than 80 mmHg or greater than 180 mmHg) generally do not affect the glomerular filtration rate due to which known local control processes within the kidney?
- Tubule-glomerular feedback
- The myogenic response
- The myogenic response and tubule-glomerular feedback
- Release of renin by the granular cells
- Release of ADH from the adrenal cortex
The myogenic response and tubule-glomerular feedback
Filtrate leaving the loop of Henle is __________ in volume and __________ to the fluid entering the loop.
- Lower; iso-osmotic
- Lower; hypo-osmotic
- Lower; hyperosmotic
- Higher; hypo-osmotic
lower; hypo-osmotic
Which of the following hormones will directly act on the collecting duct of the kidney to enhance the reabsorption of water?
- ADH
- Aldosterone
- ANP
- Renin
ADH
When mean arterial pressure increases, which of the following may increase in response?
- Water reabsorption
- GFR and ADH levels
- Urine volume
- ADH levels
- GFR and urine volume
- GFR
-GFR and urine volume
An osmotic gradient develops in the renal medulla because various parts of the loop of Henle differ from each other in which of the following characteristics?
- Active transport of solutes
- All answers
- Permeability to water
- Direction of fluid movement
All
Put the following events in the correct order:
a) Angiotensin I is converted to angiotensin II.
b) Renin is secreted by the granular cells.
c) Aldosterone is released from the adrenal glands.
d) Renin converts angiotensinogen into angiotensin I.
e) Cells in the macula densa detect a decrease in the flow of fluid (or ion concentration) in the distal tubule.
e, b, d, a, c
When insufficient water intake leads to dehydration, compensatory mechanisms to preserve plasma volume and homeostatic osmolarity include __________.
- Increasing the rate of glomerular filtration
- Increasing the amount of water that is reabsorbed from the filtrate in the collecting duct
- Increasing the amount of water excreted
- Reducing the concentration of sodium ions in the excreted urine
increasing the amount of water that is reabsorbed from the filtrate in the collecting duct
The movement of water across the late distal tubule and collecting duct is __________.
- Passive, through channels called aquaporins, and from plasma to tubule lumen
- From plasma to tubule lumen
- Passive, through channels called aquaporins, and driven by the medullary osmotic gradient
- Passive
- Through aquaporins
- Driven by the medullary osmotic gradient
Passive, through channels called aquaporins, and driven by the medullary osmotic gradient
Angiotensin II leads to an alteration in kidney function by __________.
- Reducing water appetite and reducing the water permeability of the collecting duct
- Increasing water reabsorption along the proximal tubule and increasing potassium reabsorption along the distal tubule
- Increasing water reabsorption from the collecting ducts and increasing sodium reabsorption along the distal tubules
- Decreasing sodium reabsorption along the descending loop of henle and increasing the water permeability of the ascending loop of henle
Increasing water reabsorption from the collecting ducts and increasing sodium reabsorption along the distal tubules
In the absence of ADH, which of the following will decrease?
- The medullary osmotic gradient
- Aquaporin synthesis
- Urine osmolarity, aquaporin synthesis, and the medullary osmotic gradient
- Urine volume
- Urine osmolarity
- Urine osmolarity and aquaporin synthesis
Urine osmolarity and aquaporin synthesis
Angiotensin II leads to an alteration in kidney function by __________.
- Reducing water appetite and reducing the water permeability of the collecting duct
- Increasing water reabsorption along the proximal tubule and increasing potassium reabsorption along the distal tubule
- Increasing water reabsorption from the collecting ducts and increasing sodium reabsorption along the distal tubules
- Decreasing sodium reabsorption along the descending loop of henle and increasing the water permeability of the ascending loop of henle
Increasing water reabsorption from the collecting ducts and increasing sodium reabsorption along the distal tubules
ANG II stimulates the ________
- Release of aldosterone and release of renin
- Release of aldosterone
- Vasodilation of arterioles
- Release of aldosterone and release of ADH
- Release of ADH
- Release of renin
Release of aldosterone and release of ADH
When mean arterial pressure decreases, which of the following may increase in response?
- Urine volume
- ADH levels
- ADH levels and water reabsorption
- Water reabsorption
- GFR
- GFR and urine volume
ADH levels and water reabsorption