Renal Physl 4

Question 1

What kind of regulation occurs at the nephron?

Answer 1

Dehydration and blood volume regulation

Question 2

What are the basic renal processes?

Answer 2

Filtration, reabsorption and secretion

Question 3

What are the three processes that go into the formation of urine?

Answer 3

• Glomerular filtration
• Tubular reabsorption
• Tubular secretion

Question 4

What occurs in Glomerular Filtration?

Answer 4

Blood flows into glomerular capillaries and protein free fluid leaves the glomerular capillaries

Question 4

What occurs in Glomerular Filtration?

Answer 4

Blood flows into glomerular capillaries and protein free fluid leaves the glomerular capillaries

Question 5

Where the fluid from the glomerulus go?

Answer 5

It enters bowman’s capsule

Question 6

What do not usually cross the glomerular capillary wall?

Answer 6

Proteins

Question 7

How much fluid is filtered at the glomerular capillaries?

Answer 7

180 liters per day

Question 8

What are some renal functions?

Answer 8

• Efficiently removing metabolic wastes
• Maintaining fluid and electrolyte homeostasis
• Stabilizing blood volumes and pressure

Question 9

What is filtrate subject to one it leaves the bowman’s capsule?

Answer 9

It is subject to both reabsorption and secretion

Question 10

What is Reabsortion?

Answer 10

The movement of water and solutes from the tubular lumen into the renal interstitium and back into the blood circulating

Question 11

What blood vessels circulates the nephrons?

Answer 11

The peritubular capillaries and the vasa recta

Question 12

What is secretion?

Answer 12

The selective removal of substances from circulation into the tubular filtrate that is destined for excretion

Question 13

What separates glomerular filtration from secretion?

Answer 13

Secretion is selective and glomerular filtration is not (with the exception of proteins)

Question 14

What is the selectivity of secretion useful for?

Answer 14

Enhancing metabolic waste products

Question 15

What happens once substances enter the peritubular capillaries?

Answer 15

They travel to the venous blood eventually reaching the heart and are pumped throughout the body

Question 16

Why do different segments of the nephron modify the filtrate in different ways?

Answer 16

Due to properties of the tubular epithelial cells

Question 17

Why is filtrate considered isosmotic in the bowman’s capsule?

Answer 17

Because its composition is quite similar to plasma

Question 18

What amount of filtrate is reabsorbed in the proximal tubule?

Answer 18

70% of filtrate volume

Question 19

How is solute reabsorbed in the proximal tubule?

Answer 19

It is actively absorbed so they are transported out of the lumen across the tubular epithelial cell and into the renal interstitium

Question 20

What happens when solutes are transported out of the lumen and into the renal interstitium?

Answer 20

Water follows solute and leaves the lumen and enters the interstitial space

Question 21

After water and solute are reabsorbed in the proximal tubule what is the molarity of the filtrate?

Answer 21

It is still isosmotic

Question 22

Where does filtrate go after the proximal tubule?

Answer 22

It enters the descending limb of the loop of henle

Question 23

What occurs in the descending limb of the loop of henle?

Answer 23

More water is absorbed compared to solute

Question 24

What is the permeability in the descending loop of henle?

Answer 24

It has a low permeability for solutes and a high permeability for water to leave

Question 25

What occurs in the ascending loop of henle?

Answer 25

Solute is actively reabsorbed and water is not due to relative permeability

Question 26

What is the molarity of the filtrate after leaving the ascending loop of henle?

Answer 26

It is dilutes because solute is reabsorbed and water is not

Question 27

Where does filtrate go from the ascending loop of Henle?

Answer 27

It enters the distal tubules and eventually the collecting duct

Question 28

What are the collecting duct and distal tubule sensitive to?

Answer 28

Hormones that regulate salt and water balance

Question 29

What can the Distal Tubule and Collecting duct do?

Answer 29

It can facilitate significant reabsorption of sodium and water or virtually none at at all

Question 30

What is the formula for the amount of solute excreted?

Answer 30

Amount of Solute Excrete = Amount Filtered - Amount reabsorbed + amount secreted

Question 31

What does it mean to be secreted?

Answer 31

It means that it goes into the lumen of the nephron to be excreted