Renal System 1&2 (w22)

Question 1

What is the function of the kidneys ?

Answer 1

The kidneys pressure filter the blood, producing urine.

Question 2

What are the 3 main functions of the kidney ?

Answer 2

1) filtration of blood
2) reabsorption and secretion
3) HOMEOSTASIS

Question 3

What is the functional unit of the kidney ?

Answer 3

The nephron

Question 4

How many L of plasma per day does the kidney process ?

Answer 4

180L plasma/day

Question 5

What are the 6 main substances filtered and reabsorbed by the kidney ?

Answer 5

1) Water
2) Sodium chloride e.g. reabsorbed to maintain internal O.P
3) glucose
4) Hydrogen ions
5) urea
6) Toxic substances e.g. drug metabolites

Question 6

What makes up urine in high concentrations ?

Answer 6

• urea
• ureic acid
• creatinine
• K+
• other toxic substances
  (Rest is reabsorbed)

Question 7

What are the two components of the nephron ?

Answer 7

• vascular (blood)
• tubular (filtered fluid)

Question 8

What are the two sections of the nephron ?

Answer 8

• renal cortex (outer region)
• renal medulla (inner region)

Question 9

In which direction does blood flow in the kidneys ?

Answer 9

From the afferent arteriole —> to efferent arteriole

Question 10

What is the proximal convoluted tubule (PCT) responsible for and where is it located ?

Answer 10

• is in the cortex
• responsible for most of the reabsorption/ secretion

Question 11

What is the loop of henle (LH) responsible for and where is it located ?

Answer 11

• in the cortex
• responsible for osmotic gradient in the medulla

Question 12

What occurs at the bowman’s capsule (BC) ?

Answer 12

Filtration of the blood, this encloses the glomerulus.

Question 13

What is the distal convoluted tubule responsible for and where is it located ?

Answer 13

• in the cortex
• responsible for the fine tuning of solute/water re absorption

Question 14

What are the collecting ducts/ tubules (CD) responsible for and where is it located ?

Answer 14

• on the cortex/medulla
• responsible for the fine-tuning of urine concentration

Question 15

What are the cells found in the epithelium of the bowman’s capsule and surround the capillaries ?

Answer 15

Podocytes

Question 16

What are the juxta glomerular cells responsible for ?

Answer 16

For releasing hormones (renin) that control how much water is reabsorbed (fine tuning), can also control filtration rate.

Question 17

How do the kidneys help with the long term control of blood pressure ?

Answer 17

Via the regulation of H2O and electrolytes

Question 18

What is the namer of the ball of capillaries in the kidney ?

Answer 18

Glomerulus

Question 19

What is the name of the tubular structure that surrounds this?

Answer 19

Bowman’s capsule

Question 20

What is the name of the arteriole that takes blood to the ball of capillaries?

Answer 20

Afferent arteriole

Question 21

What is the name of the arteriole that takes blood away from this ball of capillaries?

Answer 21

Efferent arteriole

Question 22

What is the functional unit of the kidney called?

Answer 22

Nephron

Question 23

What are the different parts of this functional unit?

Answer 23

• CD
• loop of Henle
• PCT
• DCT

Question 24

How is urine formed ?

Answer 24

• FILTRATION - passive ultrafiltration at the bowman’s capsule
• ACTIVE TRANSPORT (resorption and secretion) - energy driven retrieval of valuable substances along the nephron.
• OSMOSIS (resorption) - mainly in loop of Henley, PCT and collecting duct.

Question 25

What is the equation of excretion in urine ?

Answer 25

Excreted = Filtered + secreted - reabsorbed

Question 26

What is the renal corpuscle ?

Answer 26

combination of glomerulus and Bowman’s capsule, and is where filtration takes place

Question 27

What are the 3 barriers of filtration ?

Answer 27

- Glomerular capillary basement membrane - Basal lamina/membrane - Bowmans capsule epithelia (podocytes)

Question 28

What causes filtration ?

Answer 28

Capillary pressure

Question 29

What is a hematuria ?

Answer 29

Red blood cells in the urine

Question 30

What causes damage from outside the kidney ?

Answer 30

- kidney stones, tumours (renal pelvis, ureter, urinary bladder, prostate, urethra) - UTI (inflammation of urinary bladder, urethra, prostrate)

Question 31

What causes hematuria from damage inside the kidney ?

Answer 31

- inflammation of the glomeruli (e.g. glomeruli nephritis - affects filtration) - infarct - necrosis of the kidney

Question 32

What is proteinuria ?

Answer 32

When there is protein in the urine

Question 33

Which loop (descending or ascending) is permeable to water ?

Answer 33

The descending loop is permeable to water

Question 34

Which loop (ascending or descending) is impermeable to water ?

Answer 34

The ascending loop is impermeable to water

Question 35

What hormone is aldosterone and where is it released from ?

Answer 35

- steroid hormone - released from adrenal cortex