Physiology 4

Question 1

How much of the plasma that enters the glomerulus is filtered?

Answer 1

20%

Question 2

Glomerular filtration rate?

Answer 2

125ml/min

= 180 litres per day

Question 3

Roughy how many times a day is plasma filtered?

Answer 3

65

Question 4

How much glucose reabsorbed?

Answer 4

100%

Question 5

How much urea is reabsorbed?

Answer 5

50%

Question 6

Percentage of amino acids reabsorbed?

Answer 6

100%

Question 7

Rate of fluid getting reabsorbed into the proximal tubule?

Answer 7

about 80mil/min

Question 8

Substances reabsorbed in the proximal tubule? (SAPSL)

Answer 8

Sugar
Amino acids
Phosphate
Sulphate
Lactate

Question 9

Substances secreted into the proximal tubule?

Answer 9

H+
Hippurates
Neurotransmitters
Bile pigments
Uric acid
Drugs
Toxins

Question 10

Energy is directly required to operate the carrier and move the substrate against its concentration gradient

Answer 10

Primary active transport

Question 11

The carrier molecule is transported coupled to the concentration gradient of an ion (usually Na+)

Answer 11

Secondary active transport

Question 12

Passive carrier-mediated transport of a substance down its concentration gradient

Answer 12

Facilitated diffusion

Question 13

Diffusion through the lipid bilayer

Answer 13

O2, CO2

Question 14

Diffusion through channels

Answer 14

Na+

Question 15

Facilitated diffusion

Answer 15

Glucose

Question 16

Primary active transport

Answer 16

Na+ K+ and the ATP thing

Question 17

Secondary active transport

Answer 17

Na+ and glucose in their little transport thing

Question 18

Percentage of salt and water reabsorbed in the proximal tubule?

Answer 18

67%

Question 19

What drives Na+ rabsorption?

Answer 19

The basolateral Na+ K+ ATPase

Question 20

Na+ reabsorption also drives reabsorption of what?

Answer 20

Cl-

Question 21

How is water reabsorbed?

Answer 21

Reabsorbed by osmosis

Question 22

How does glucose move from the lumen into the cell?

Answer 22

Cotransport (glucose and Na+)

Question 23

How does glucose move from the cell into the interstitial space?

Answer 23

Facilitated diffusion

Question 24

Transport maximum for glucose?

Answer 24

about 2mmol/min

Question 25

Which part of the nephron generates a cortico-medullary solute concentration gradient?

Answer 25

The loop of henle -This enables the formation of hypertonic urine

Question 26

This segment does not reabsorb NaCl and is highly permeable to water?

Answer 26

Descending limb

Question 27

Along the entire length of the ascending limb Na+ & Cl- are being reabsorbed

Answer 27

Ascending limb

Question 28

Thick upper limb of AL, which type of transport?

Answer 28

Active transport

Question 29

Thin (lower) AL, which type of transport?

Answer 29

Passive transport

Question 30

What type of diuretics block the triple co-transporter?

Answer 30

Loop diuretics

Question 31

ISO-OSMOTIC, enters or leaves the tubule?

Answer 31

ISO-osmotic LEAVES the proximal tubule

Question 32

HYPO-OSMOTIC, enters or leaves the tubule?

Answer 32

Hypo-osmotic ENTERS the distal tubule

Question 33

Urea: how does it pass into the loop of henle and is the distal permeable to it?

Answer 33

Passively diffuses into the loop of henle | Distal tubule is not permeable to urea

Question 34

How much urea is absorbed in the collecting duct? | And what promotes this?

Answer 34

About 50% urea | ADH promotes this

Question 35

Why is countercurrent multiplication important?

Answer 35

To enable the kidney to produce urine of different volume and concentration according to the amounts of circulating antidiuretic hormone (ADH = vasopressin)

Question 36

Roughly how much urine do you make per minute?

Answer 36

Vu on normal fluid intake = ~1 ml/min | Can be 0.3-25 ml/min

Question 37

Essential blood flow through the medulla tends to wash away NaCl and urea. How is this problem minimised? (3 reasons)

Answer 37

Vasa recta capillaries follow hairpin loops Vasa recta capillaries freely permeable to NaCl and water Blood flow to vasa recta is low (few juxtamedullary nephrons)

Question 38

Which two components make up the countercurrent system?

Answer 38

Countercurrent multiplication and countercurrent exchanger and the VASA RECTA

Question 39

In which type of nephrons does the vasa recta run alongside?

Answer 39

Vasa recta runs in JUXTAGLOMERULAR nephrons

Question 40

The high medullary osmolarity allows the production of hypertonic urine in the presence of _____?

Answer 40

In the presence of ADH