A/P II Exam 3
As the filtrate passes through the nephron... Volume decreases most in the proximal tubule Concentration decreases in the descending loop Concentration increases in the ascending loop Volume increases in the descending loop
Volume decreases most in the proximal tubule
When blood pressure drops what to JG cells do?
Release renin into blood stream
Which of the following does NOT normally appear in the filtrate? Water Urea Albumin Glucose
Albumin
High Hydrostatic pressure dominates at _____ end of most blood vessels
Arteriolar Pushes water out of vessel
Water is a nonpolar solvent; allows water to transport and deliver a large number of solutes throughout body. A) True B) False
False (water is polar)
The filtration fraction averages what percentage of the plasma that enters the glomerulus? 0% 20% 50% 70%
20%
Concentrations of NaCl, calcium and bicarbonate ions are higher in... A) ECF B) Cytosol
A) ECF
Blood descending into the medulla in the vasa recta... Loses both sodium chloride and water Gains both sodium chloride and water Gains sodium chloride and loses water Does not change
Gains NaCl and loses water
Define GFR
Glomerular Filtration Rate: Amount of filtrate formed by BOTH kidneys in one minute. 125 ml/min: all 3 liters of blood plasma are filtered 60 times per day
Choose the CORRECT pathway followed by filtrate as it becomes urine: Proximal tubule, loop, glomerulus, distal tubule, collecting duct Proximal tubule, loop, distal tubule, collecting duct, glomerulus Glomerulus, collecting duct, proximal tubule, loop, distal tubule Glomerulus, proximal tubule, loop, distal tubule, collecting duct
Glomerulus, proximal tubule, loop, distal tubule, collecting duct
What results from overhydration?
Hyponatremia (low salt conc.)
Aldosterone... Is released from the adrenal medulla Acts on the proximal tubule Promotes sodium excretion Increases blood volume if ADH is present
Increases blood volume if ADH is present
Glomerulonephritis
Inflammation of glomerular capillaries INCREASES blood flow and capillary permeability.
Countercurrent multiplication... Occurs only in cortical nephrons Creates the cortical concentration gradient Requires interaction between the proximal and distal tubules Involves filtrate flowing in opposite directions through limbs of the loop
Involves filtrate flowing in opposite directions through limbs of the loop
Active transport in the thick ascending limb of the loop... Is driven by Na+/K+/2Cl symporters Is driven by Na+/K+ pumps Is driven by Na+/K+/2Cl antiporters Is not affected by the concentration of available NaCl
Is driven by Na+/K+/2Cl- symporters
Glomerular hydrostatic pressure... Is less than that of most body capillaries Is increased by the high resistance efferent arteriole Opposes filtration of fluid from the glomerulus Pulls fluid into the glomerular capillary
Is increased by the high resistance efferent arteriole
Hydrostatic pressure... Is the pressure created by proteins in a fluid Is higher than the blood pressure Is the force of fluid on the wall of its container Pulls fluid into the capillaries
Is the force of fluid on the wall of its container
Net filtration pressure at the glomerulus... Is less than that of most body capillaries Is typically about 10 mm Hg Is not related to the glomerular filtration rate Pulls fluid into the glomerular capillary
Is typically about 10 mmHg
Blood ascending into the cortex in the vasa recta... Loses sodium chloride and gains water Gains both sodium chloride and water Gains sodium chloride and loses water Does not change
Loses NaCl and gains water
Angiotensin-I is converted into angiotensin-II in the... Kidneys Liver Lungs Stomach
Lungs
Which of the following is NOT part of the filtration membrane? Podocytes Macula densa Basal lamina Capillary endothelial cells
Macula Densa
Water is reabsorbed from the collecting system because of? Hormone levels Cortical interstitial fluid concentration Medullary interstitial fluid concentration NaCl concentrations in the bloodstream
Medullary interstitial fluid conc.
Net Filtration Pressure
NFP=GHP-(GCOP + CHP)
Macula Densa
Negative feedback loop controls pressure in glomerulus in response to NaCl conc. of filtrate
Which of the following does NOT increase renin release? Parasympathetic stimulation Low glomerular hydrostatic pressure Decreased sodium ion levels in plasma Low blood pressure
Parasympathetic Stimulation
The Basal Lamina is composed of collagen fibers that block ______ from entering capsular space
Plasma Proteins
The layer of the filtration membrane that is LEAST permeable is the? Podocytes (visceral layer of capsule) Macula densa Basal lamina Capillary endothelial cells
Podocytes
Angiotensin-II does NOT.. Promote aldosterone release Promote vasodilation of efferent arterioles Promote sodium, chloride, and water reabsorption Promote the sensation of thirst
Promote vasodilation of efferent arterioles
Glomerular colloidal osmotic pressure... Is the pressure created by ions in a fluid Is higher than the blood pressure Is the force of fluid on the wall of its container Pulls fluid into the capillaries
Pulls fluid into the capillaries
Colloid Osmotic Pressure
Pulls water into capillaries by osmosis
The distal tubule and collecting duct... Reabsorb most of remaining water Reabsorb filtered hydrogen ions Reabsorb filtered calcium and magnesium ions Reabsorb filtered uric acid
Reabsorb most of the remaining water
The proximal tubule... Reabsorbs 100% of the filtered water Reabsorbs filtered hydrogen ions Reabsorbs about 90% of filtered bicarbonate ions Reabsorbs filtered uric acid
Reabsorbs about 90% of the filtered bicarbonate ions
The ascending limb of the nephron loop... Reabsorbs sodium and chloride Reabsorbs sodium, chloride, and water Reabsorbs water only Reabsorbs glucose, amino acids, and other organic solutes
Reabsorbs sodium and chloride
The thin descending limb of the nephron loop... Reabsorbs sodium and chloride Reabsorbs sodium, chloride, and water Reabsorbs water only Reabsorbs glucose, amino acids and other organic solutes
Reabsorbs water only
Facultative water reabsorption... Increases urine volume Produces dilute urine Requires ADH release Occurs when water content of body fluids is too high
Requires ADH release
The composition of the filtrate is based primarily on... Solubility Polarity Charge Size
Size
What substances can be found in filtrate?
Small substances (water, electrolytes, acids, bases, metabolic waste)
The kidneys produce dilute urine when... Solute concentration of body fluids is too high Solute concentration of body fluids is too low Solute concentration of body fluids is normal Water content of body fluids is too low
Solute conc. of body fluids is too low
Blood loss causes fluid depletion, or hypovolemia, where amount of solute and water lost is equal. A) True B) False
True
Hypercalcemia is defined as a plasma Ca2+ above 10.5 mg/dl; associated with hyperparathyroidism, excess vitamin D, bone disorders, and renal failure A) True B) False
True
When intravenous access is required over long term, a larger port may be inserted in a vein such as subclavian or internal jugular vein; known as central lines. A) True B) False
True
High Osmotic pressure dominates at ____ end of most blood vessels
Venular. Pulls water back into vessel.
Concentrations of Proteins, Potassium, and Magnesium ions are higher in... A) ECF B) Cytosol
B) Cytosol
Is an important component of bone tissue... A) Chloride B) Sodium C) Magnesium D) Potassium
C) Magnesium
The vasa recta... Create the medullary concentration gradient Arise from the interlobar veins Exchange materials with the collecting system Contain blood flowing in the opposite direction from the filtrate in the loop
Contain blood flowing in the opposite direction from the filtrate in the loop
Angiotensin-converting enzyme... Converts angiotensinogen into angiotensin-I Stimulates the thirst centers in the hypothalamus Converts angiotensin-I into angiotensin-II Inactivates angiotensin-II
Converts angiotensin-I into angiotensin-II
Hydrogen ion plays an important role in following EXCEPT: A) digestion of food B) inactivation of microbes and pathogens C) intracellular digestion in lysosomes D) Act as buffer
D)Act as buffer
Why can't albumin be found in filtrate
Diameter is 7.1 nm. Too large for visceral layer (podocytes)
Hypokalemia causes
Diuretics that lead to excess K+ loss in urine Hypo: less than 3.9 mEq/L
Proteins and potassium, magnesium, sulfate, and monohydrogen phosphate (HPO42-) ions have a much higher concentration in plasma than in cytosol. A) True B) False
False
Sodium ion concentrations are kept high within cell by Na+/K+ ATPase pumps and due to low plasma membrane Na+ permeability that prevents leakage back into cell. A)True B) False
False