Renal

Question 1

Non excretory functions of kidney

Answer 1

1. Electrolyte reg
2. Blood pH
3. Blood volume
4. BP
5. Blood osmolality
6. Hormone production
7. Blood glucose reg
8. Detoxification

Question 2

Functions of JG apparatus

Answer 2

1. Autoregulation of GFR and renal blood flow
2. BP regulation
3. Blood volume
4. ECF volume and osmolality

Question 3

Factors influencing GFR

Answer 3

Filtration coefficient
Starlings forces
Renal blood flow

Question 4

Normal kf value

Answer 4

12.5 mL/ min/mmHg for both kidneys

Question 5

Kf

Answer 5

Product of permeability and filtering surface area of capillaries

Question 6

Capillary hydrostatic pressure

Answer 6

45mmHg

Facilitates

Question 7

Colloidal osmotic pressure

Answer 7

25 mmHg

Opposes

Question 8

Hydrostatic pressure in Bowman’s capsule

Answer 8

10 mm Hg

Opposes

Question 9

Colloidal osmotic pressure in Bowman’s capsule

Answer 9

0

Question 10

GFR

Answer 10

= Net effective filtration pressure * Kf
= 10 * 12.5
125mL/min

Question 11

Filtration fraction

Answer 11

Fraction of RBF filtered
GFR/RBF
0.2

Question 12

Extraction ratio

Answer 12

Percentage of substance removed from blood

Question 13

Limits of autoregulation

Answer 13

Absent below 80 and above 180 mm Hg

Question 14

Myogenic theory of autoregulation

Answer 14

Inc. in renal perfusion pressure
Inc. RBF GFR
Stretch of smooth muscle in aff. arteriole
Smooth muscle
Vasoconstriction
RBF GFR Dec.

Question 15

Tubuloglomerular feedback mechanism

Answer 15

Sensor: macula densa
Inc. RBF GFR
Inc. flow to macula densa
Inc. Na+, Cl-  at macula densa
Inc. transport of Na, Cl through macula densa cells
Inc. NaK ATPase
Inc. adenosine formation
Contraction of mesangial cells
Contraction of afferent arteriole
Decrease pore size of podocytes
Dec. RBF GFR

Question 16

Transport maximum

Answer 16

Maximum amount of substance absorbed by tubules of both kidneys in 1 min

Question 17

Glucose absorption in PCT

Answer 17

Lumen to epithelium - secondary active transport SGLT2

Epithelium to capillary - facilitated diffusion GLUT2

Question 18

Transport maximum of glucose

Answer 18

375 mg/min

Question 19

Substances absorbed in PCT

Answer 19

1. All essential AA
2. Proteins
3. Creatine
4. Sulfates
5. Phosphates
6. Uric acid
7. Vitamins
8. Water
9. Sodium
10. HCO3-
11. K+

Question 20

Hormones affecting reabsorption

Answer 20

Aldosterone 
Angiotensin 2
ADH
ANP
Parathyroid
Calcitonin
Prostaglandins

Question 21

Na+ absorption

Answer 21

67 percent PCT - co with Cl, HCO3-, glucose, H+
20 percent LH
Early DCT - active
Late DCT - exchange with K, H+