BIO 305 Renal Exam With Accurate Solutions
What is the main function of the renal system? - ANSWER To maintain homeostasis of
interstitial (extracellular) fluid composition and volume.
In other words, water balance and electrolyte management.
Name 2 excretory functions of the kidney. - ANSWER H2O balance; Electrolyte
balance; pH balance; Elimination of N-wastes from metabolism
Name 2 non-excretory functions of the kidney. - ANSWER Erythropoietin;
Prostaglandin formation; Renin secretion; Metabolize vit. D; Degrades insulin
Starting at the afferent arteriole, name (in order) the major structures of the vertebrate
nephron, ending in a minor calyx. - ANSWER a. Afferent arteriole
b. Glomerulus
c. Bowman's capsule
d. Proximal tube
e. Descending and ascending limb
f. Distal convoluted tube
g. Collecting duct
h. Minor calyx
Name the three main renal processes. - ANSWER Filtration
Tubular Reabsorption
Tubular secretion
Name where each one occurs in the Nephron - ANSWER Filtration -Glomerulus
, Tubular Reabsorption - Proximal and Distal Convoluted tubules
Tubular Secretion - Proximal and Distal Convoluted tubules
Describe what is happening for each of the three main Renal functions - ANSWER
Filtration-Fluids from the blood are 'pushed' from the glomerulus into the nephron via
Bowman's capsule.
Tubular Reabsorption-Fluids and filtered materials are moved from the nephron back
into the blood (passive & active processes).
Tubular Secretion-Fluids and filtered materials in the blood are moved from the blood
back into the nephron (passive & active processes).
What is the basic main function for the Loop of Henle? - ANSWER To create an osmotic
gradient in the renal medulla increasing from the cortex to the papilla
Outline how a concentrated urine is formed as the filtrate flows through the Loop of
Henle and then the Collecting Duct. - ANSWER The Loop of Henle creates the osmotic
gradient in the renal medulla. As the filtrate exits the distal convoluted tubule of the
nephron and enters the collecting duct (CD), it begins to encounter a surrounding
environment that is has lower water concentration ('saltier'). - If ADH is present, the CD
membrane is more permeable to water. - Since the environment has less water than the
filtrate, water leaves the CD back into the kidney (to be reabsorbed by the capillaries). -
As the filtrate moves down the CD, it continually encounters an increasingly 'saltier'
environment, which continually removes more and more water from the filtrate in the
CD, making the filtrate more and more concentrated. - By the time the filtrate reaches
the papilla, it is now a concentrated urine.
Describe the structure of the juxtaglomerular apparatus - ANSWER
How does it contribute to the control of Glomerular Filtration Rate? - ANSWER When
the juxtaglomerular apparatus senses low flow through the efferent arteriole of the
glomerulus, it releases Renin into the arteriole. Renin operates to increase blood volume
(please see Question 7). By increasing volume, blood pressure is increased, and so GFR
is increased. This is done reflexively, with no control from other areas.
. Briefly outline (in order), starting with the secretion of Renin, the basic sequence of
What is the main function of the renal system? - ANSWER To maintain homeostasis of
interstitial (extracellular) fluid composition and volume.
In other words, water balance and electrolyte management.
Name 2 excretory functions of the kidney. - ANSWER H2O balance; Electrolyte
balance; pH balance; Elimination of N-wastes from metabolism
Name 2 non-excretory functions of the kidney. - ANSWER Erythropoietin;
Prostaglandin formation; Renin secretion; Metabolize vit. D; Degrades insulin
Starting at the afferent arteriole, name (in order) the major structures of the vertebrate
nephron, ending in a minor calyx. - ANSWER a. Afferent arteriole
b. Glomerulus
c. Bowman's capsule
d. Proximal tube
e. Descending and ascending limb
f. Distal convoluted tube
g. Collecting duct
h. Minor calyx
Name the three main renal processes. - ANSWER Filtration
Tubular Reabsorption
Tubular secretion
Name where each one occurs in the Nephron - ANSWER Filtration -Glomerulus
, Tubular Reabsorption - Proximal and Distal Convoluted tubules
Tubular Secretion - Proximal and Distal Convoluted tubules
Describe what is happening for each of the three main Renal functions - ANSWER
Filtration-Fluids from the blood are 'pushed' from the glomerulus into the nephron via
Bowman's capsule.
Tubular Reabsorption-Fluids and filtered materials are moved from the nephron back
into the blood (passive & active processes).
Tubular Secretion-Fluids and filtered materials in the blood are moved from the blood
back into the nephron (passive & active processes).
What is the basic main function for the Loop of Henle? - ANSWER To create an osmotic
gradient in the renal medulla increasing from the cortex to the papilla
Outline how a concentrated urine is formed as the filtrate flows through the Loop of
Henle and then the Collecting Duct. - ANSWER The Loop of Henle creates the osmotic
gradient in the renal medulla. As the filtrate exits the distal convoluted tubule of the
nephron and enters the collecting duct (CD), it begins to encounter a surrounding
environment that is has lower water concentration ('saltier'). - If ADH is present, the CD
membrane is more permeable to water. - Since the environment has less water than the
filtrate, water leaves the CD back into the kidney (to be reabsorbed by the capillaries). -
As the filtrate moves down the CD, it continually encounters an increasingly 'saltier'
environment, which continually removes more and more water from the filtrate in the
CD, making the filtrate more and more concentrated. - By the time the filtrate reaches
the papilla, it is now a concentrated urine.
Describe the structure of the juxtaglomerular apparatus - ANSWER
How does it contribute to the control of Glomerular Filtration Rate? - ANSWER When
the juxtaglomerular apparatus senses low flow through the efferent arteriole of the
glomerulus, it releases Renin into the arteriole. Renin operates to increase blood volume
(please see Question 7). By increasing volume, blood pressure is increased, and so GFR
is increased. This is done reflexively, with no control from other areas.
. Briefly outline (in order), starting with the secretion of Renin, the basic sequence of
