Question 1

Located entirely within the cortex, reabsorption of water and certain solutes from which region is under hormonal control?

Accepted Answer

A)  collecting duct 
B)  Bowman's capsule 
C)  distal tubule 
D)  proximal tubule 
E)  loop of Henle 
A)  collecting duct 
B)  Bowman's capsule 
C)  distal tubule 
D)  proximal tubule 
E)  loop of Henle C

Question 2

Ultimately, our ability to assess the function of the kidneys involves measuring what is excreted in urine. Describe the methods used to assess the function of the kidneys (glomerular filtration rate [GFR]), including the calculations and ions involved in that assessment.

Accepted Answer

In its simplest form, excretion rate can be measured as an ion's filtration rate + secretion rate - reabsorption rate. Filtration rate can be determined as filtered load (GFR × plasma concentration of an ion). Excretion gives an indication of the net direction of movement of an ion. If the amount of a solute excreted per minute is less than its filtered load, then the solute was reabsorbed. If the amount of a solute excreted is greater than filtered load, then that solute was secreted. However, this measurement reflects which force (reabsorption or secretion) is dominating for a particular solute, which means that both are usually occurring at the same time. The rate at which a solute is excreted can be described in terms of clearance: a measure of the volume of plasma from which a solute is completely removed. Clearance is calculated as excretion rate/plasma concentration. Clearance gives an indication of how the kidneys are handling one solute relative to another. Clinically, clearance is determined by three variables: (urine concentration of a solute × urine flow rate)/plasma concentration of a solute. These are easily measured clinically. Clearance also provides a way to measure GFR. If a substance is freely filtered and is neither reabsorbed nor secreted, then the amount of that substance in the urine must be equal to the amount filtered (filtered load). In this case, the clearance of this substance is equal to GFR. Inulin is a polysaccharide that is neither secreted nor reabsorbed. In this case, GFR = (urine concentration of inulin × urine flow rate)/plasma concentration of inulin. Another less invasive method for measuring GFR involves measuring creatinine, a byproduct of muscle metabolism. Only a small amount of creatinine is secreted and none is reabsorbed.

Question 3

If the clearance of a substance is greater than glomerular filtration rate, then that substance was (reabsorbed / secreted) in the tubules.

Accepted Answer

secreted

Question 4

What two structures make up the renal corpuscle?

Accepted Answer

A)  afferent and efferent arterioles 
B)  proximal straight and proximal convoluted tubules 
C)  Bowman's capsule and glomerulus 
D)  nephron and collecting duct 
E)  major and minor calyces 
A)  afferent and efferent arterioles 
B)  proximal straight and proximal convoluted tubules 
C)  Bowman's capsule and glomerulus 
D)  nephron and collecting duct 
E)  major and minor calyces

Question 5

As fluid moves out of the glomerular capillaries, it passes through gaps in the podocytes called slit pores, whose size is regulated by what?

Accepted Answer

A)  glomerular capillary 
B)  fenestrations 
C)  corpuscle 
D)  slit diaphragm 
E)  slit muscle 
A)  glomerular capillary 
B)  fenestrations 
C)  corpuscle 
D)  slit diaphragm 
E)  slit muscle

Question 6

What is the functional unit of the kidney?

Accepted Answer

A)  loop of Henle 
B)  nephron 
C)  glomerulus 
D)  proximal tubule 
E)  collecting ducts 
A)  loop of Henle 
B)  nephron 
C)  glomerulus 
D)  proximal tubule 
E)  collecting ducts

Question 7

Which cells of the distal tubule secrete a paracrine in response to changes in the filtrate flow rate?

Accepted Answer

A)  macula densa cells 
B)  mesangial cells 
C)  granular cells 
D)  endothelial cells 
E)  podocytes 
A)  macula densa cells 
B)  mesangial cells 
C)  granular cells 
D)  endothelial cells 
E)  podocytes

Question 8

What are a small percentage of the nephrons in the kidneys that function in the maintenance of the osmotic gradient in the medullary region of the kidney called?

Accepted Answer

A)  convoluted nephrons 
B)  juxtamedullary nephrons 
C)  cortical nephrons 
D)  arcuate nephrons 
E)  interlobular nephrons 
A)  convoluted nephrons 
B)  juxtamedullary nephrons 
C)  cortical nephrons 
D)  arcuate nephrons 
E)  interlobular nephrons

Question 9

By the time filtrate reaches the loop of Henle, what percentage of the sodium and water has been reabsorbed?

Accepted Answer

A)  90% 
B)  50% 
C)  100% 
D)  70% 
E)  1% 
A)  90% 
B)  50% 
C)  100% 
D)  70% 
E)  1%

Question 10

Most reabsorption occurs in the_______and is_______.

Accepted Answer

A)  proximal tubule : not regulated 
B)  proximal tubule : regulated and is . 
C)  distal tubule and collecting duct : not regulated 
D)  loop of Henle : regulated 
E)  distal tubule and collecting duct : regulated 
A)  proximal tubule : not regulated 
B)  proximal tubule : regulated and is . 
C)  distal tubule and collecting duct : not regulated 
D)  loop of Henle : regulated 
E)  distal tubule and collecting duct : regulated

Question 11

In order for a nephron to act as a filter, the plasma must be able to exit the vasculature. Describe the balance of Starling's forces across the glomerular capillaries that drives the movement of plasma and the pathway that plasma takes as it becomes filtrate.

Accepted Answer

Blood enters the glomerular capillaries

Question 12

Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates water reabsorption?

Accepted Answer

A)  atrial natriuretic peptide 
B)  erythropoietin 
C)  antidiuretic hormone 
D)  aldosterone 
E)  renin 
A)  atrial natriuretic peptide 
B)  erythropoietin 
C)  antidiuretic hormone 
D)  aldosterone 
E)  renin

Question 13

What structure filters the blood to regulate its composition?

Accepted Answer

A)  kidneys 
B)  liver 
C)  ureter 
D)  bladder 
E)  urethra 
A)  kidneys 
B)  liver 
C)  ureter 
D)  bladder 
E)  urethra

Question 14

What is the GFR/renal plasma flow equal to?

Accepted Answer

A)  filtration fraction 
B)  excretion rate 
C)  filtered load 
D)  clearance 
E)  renal blood flow 
A)  filtration fraction 
B)  excretion rate 
C)  filtered load 
D)  clearance 
E)  renal blood flow

Question 15

How does the sympathetic nervous system decrease glomerular filtration rate?

Accepted Answer

A)  stimulates contraction of mesangial cells 
B)  stimulates constriction of the afferent arteriole only 
C)  stimulates relaxation of the mesangial cells 
D)  stimulates constriction of both the afferent and efferent arterioles 
E)  stimulates constriction of the efferent arteriole only 
A)  stimulates contraction of mesangial cells 
B)  stimulates constriction of the afferent arteriole only 
C)  stimulates relaxation of the mesangial cells 
D)  stimulates constriction of both the afferent and efferent arterioles 
E)  stimulates constriction of the efferent arteriole only

Question 16

Which of the following is FALSE concerning glucose transport across the proximal tubule?

Accepted Answer

A)  Glucose is actively transported across the apical membrane by cotransport with sodium. 
B)  Glucose is normally 100% reabsorbed. 
C)  Glucose moves by paracellular transport. 
D)  Glucose transport requires energy. 
E)  Glucose is passively transported across the basolateral membrane by facilitated diffusion. 
A)  Glucose is actively transported across the apical membrane by cotransport with sodium. 
B)  Glucose is normally 100% reabsorbed. 
C)  Glucose moves by paracellular transport. 
D)  Glucose transport requires energy. 
E)  Glucose is passively transported across the basolateral membrane by facilitated diffusion.

Question 17

The juxtaglomerular apparatus describes the unique region of the nephron where the

Accepted Answer

A)  afferent arteriole is in contact with the proximal tubule. 
B)  afferent and efferent arterioles are in contact with the distal tubule. 
C)  afferent arteriole is in contact with the distal tubule. 
D)  efferent arteriole is in contact with the distal tubule. 
E)  afferent and efferent arterioles are in contact with the proximal tubule. 
A)  afferent arteriole is in contact with the proximal tubule. 
B)  afferent and efferent arterioles are in contact with the distal tubule. 
C)  afferent arteriole is in contact with the distal tubule. 
D)  efferent arteriole is in contact with the distal tubule. 
E)  afferent and efferent arterioles are in contact with the proximal tubule.

Question 18

When carrier proteins are saturated, they are said to be working at what?

Accepted Answer

A)  diminished capacity 
B)  active reabsorptive state 
C)  transport maximum 
D)  increased capacity 
E)  increased affinity 
A)  diminished capacity 
B)  active reabsorptive state 
C)  transport maximum 
D)  increased capacity 
E)  increased affinity

Question 19

Which of the following describes movement from renal tubules into the peritubular capillaries?

Accepted Answer

A)  secretion 
B)  micturition 
C)  excretion 
D)  reabsorption 
E)  filtration 
A)  secretion 
B)  micturition 
C)  excretion 
D)  reabsorption 
E)  filtration

Question 20

In diabetes mellitus, why does polyuria occur?

Accepted Answer

A)  Hypoglycemia causes the excretion of a dilute urine. 
B)  Hyperglycemia causes increased permeability of the renal tubules to water. 
C)  A lack of ADH decreases water reabsorption. 
D)  A lack of insulin decreases water reabsorption. 
E)  Hyperglycemia causes some glucose to remain in the renal tubules which pulls water with it by osmosis. 
A)  Hypoglycemia causes the excretion of a dilute urine. 
B)  Hyperglycemia causes increased permeability of the renal tubules to water. 
C)  A lack of ADH decreases water reabsorption. 
D)  A lack of insulin decreases water reabsorption. 
E)  Hyperglycemia causes some glucose to remain in the renal tubules which pulls water with it by osmosis.

Exam 18: The Urinary System: Renal Function

Located entirely within the cortex, reabsorption of water and certain solutes from which region is under hormonal control?

Ultimately, our ability to assess the function of the kidneys involves measuring what is excreted in urine. Describe the methods used to assess the function of the kidneys (glomerular filtration rate [GFR]), including the calculations and ions involved in that assessment.

If the clearance of a substance is greater than glomerular filtration rate, then that substance was (reabsorbed / secreted) in the tubules.

What two structures make up the renal corpuscle?

As fluid moves out of the glomerular capillaries, it passes through gaps in the podocytes called slit pores, whose size is regulated by what?

What is the functional unit of the kidney?

Which cells of the distal tubule secrete a paracrine in response to changes in the filtrate flow rate?

What are a small percentage of the nephrons in the kidneys that function in the maintenance of the osmotic gradient in the medullary region of the kidney called?

By the time filtrate reaches the loop of Henle, what percentage of the sodium and water has been reabsorbed?

Most reabsorption occurs in the_______and is_______.

In order for a nephron to act as a filter, the plasma must be able to exit the vasculature. Describe the balance of Starling's forces across the glomerular capillaries that drives the movement of plasma and the pathway that plasma takes as it becomes filtrate.

Tubular epithelial cells of the collecting duct and distal tubule contain receptors for what hormone that stimulates water reabsorption?

What structure filters the blood to regulate its composition?

What is the GFR/renal plasma flow equal to?

How does the sympathetic nervous system decrease glomerular filtration rate?

Which of the following is FALSE concerning glucose transport across the proximal tubule?

The juxtaglomerular apparatus describes the unique region of the nephron where the

When carrier proteins are saturated, they are said to be working at what?

Which of the following describes movement from renal tubules into the peritubular capillaries?

In diabetes mellitus, why does polyuria occur?

Introduction to Physiology

The Cell: Structure and Function

Cell Metabolism

Cell Membrane Transport

Chemical Messengers

The Endocrine System: Endocrine Glands and Hormone Actions

Nerve Cells and Electrical Signaling

Synaptic Transmission and Neural Integration

The Nervous System: Central Nervous System

The Nervous System: Sensory Systems

The Nervous System: Autonomic and Motor Systems

Muscle Physiology

The Cardiovascular System: Cardiac Function

The Cardiovascular System: Blood Vessels, Blood Flow, and Blood Pressure

The Cardiovascular System: Blood

The Respiratory System: Pulmonary Ventilation

The Respiratory System: Gas Exchange and the Regulation of Breathing

The Urinary System: Fluid and Electrolyte Balance

The Gastrointestinal System

The Endocrine System Regulation of Energy Metabolism and Growth

The Reproductive System

The Immune System

Diabetes Mellitus

Filters

Most reabsorption occurs in the_and is_.