Physiology 2 - Structure and Function of the Kidneys

Question 1

Roughly how much salt do the kidneys excrete per day?

Answer 1

10g

Question 2

What are some examples of metabolic waste products which are excreted by the kidneys?

Answer 2

Urea, creatinine, bilirubin

Question 3

Which hormone is secreted by the kidneys to control arterial blood pressure?

Answer 3

Renin

Question 4

Which hormone is secreted by the kidneys to stimulate red blood cell production?

Answer 4

Erythropoietin

Question 5

What is the functional unit of the kidney?

Answer 5

Nephron

Question 6

What are the three main functions of the nephron?

Answer 6

Filtration, secretion, reabsorption

Question 7

The initial tubular fluid formed by glomerular filtration passes from the glomerulus into where?

Answer 7

Bowman’s capsule

Question 8

Describe the flow of tubular fluid once it has exited the Bowman’s capsule?

Answer 8

Proximal tubule - loop of Henle - distal tubule - collecting duct

Question 9

The collecting ducts empty urine into where?

Answer 9

Renal pelvis

Question 10

Histologically, the tubules of the nephron are made up of what?

Answer 10

A single layer of epithelial cells

Question 11

What blood vessel drains blood into the glomerulus?

Answer 11

Afferent arteriole

Question 12

Blood leaves the glomerulus into which vessel?

Answer 12

Efferent arteriole

Question 13

In the vast majority of nephrons, where does blood pass into from the efferent arteriole?

Answer 13

Peritubular capillaries

Question 14

The juxtaglomerular apparatus is a small portion of what part of the nephron, that passes between the afferent and efferent arterioles?

Answer 14

Distal tubule

Question 15

What is the most common type of nephron in the kidneys?

Answer 15

Cortical

Question 16

20% of the nephrons in the kidneys are what type?

Answer 16

Juxtamedullary

Question 17

In which type of nephron is the loop of Henle longer?

Answer 17

Juxtamedullary

Question 18

Juxtamedullary nephrons do not have peritubular capillaries. What do they have instead?

Answer 18

Vasa recta

Question 19

The vasa recta follows the route taken by which part of the nephron?

Answer 19

Loop of Henle

Question 20

What is the purpose of the juxtamedullary nephrons?

Answer 20

To produce a more concentrated urine

Question 21

Which is larger in diameter- the afferent or efferent arteriole?

Answer 21

Afferent

Question 22

If the smooth muscle of the afferent arteriole contracts, what happens to the blood supply to the glomerulus?

Answer 22

Decreased

Question 23

If the smooth muscle of the afferent arteriole relaxes, what happens to the blood supply to the glomerulus?

Answer 23

Increased

Question 24

Which cells make up the inner layer of the Bowman’s capsule?

Answer 24

Podocytes

Question 25

What is located between the endothelial cells of the glomerulus capillary and the podocytes of the Bowman's capsule?

Answer 25

Basement membrane

Question 26

Does the basement membrane of a nephron contain any cells?

Answer 26

No

Question 27

What is the purpose of the granular cells in the juxtaglomerular apparatus?

Answer 27

To secrete renin

Question 28

What is the purpose of the macula densa cells in the juxtaglomerular apparatus?

Answer 28

To sense the salt concentration of the tubular fluid

Question 29

If there is too much salt in the tubular fluid, what is the action of the macula densa cells in the juxtaglomerular apparatus?

Answer 29

Contract smooth muscle cells in the afferent arteriole

Question 30

If there is too little salt in the tubular fluid, what is the action of the macula densa cells in the juxtaglomerular apparatus?

Answer 30

Relax smooth muscle cells in the afferent arteriole

Question 31

What percentage of blood passing through the glomerulus becomes tubular fluid?

Answer 31

20%

Question 32

What is the normal glomerular filtration rate?

Answer 32

125ml/min

Question 33

If the rate of filtration of a substance is higher than the rate of excretion of the same substance, what has happened to that substance in the nephron?

Answer 33

Net reabsorption

Question 34

If the rate of filtration of a substance is lower than the rate of excretion of the same substance, what has happened to that substance in the nephron?

Answer 34

Net secretion