lecture 25: renal physiology 1

Question 1

main functions of the kidney

Answer 1

• water and electrolyte balance
• maintain blood osmolarity
• regulate blood volume
• regulation of blood pressure
• execrete metabolic waste/foreign chemicals
• regulate blood pH
• regulate RBC production
• regulate hormone production
• regulate blood glucose levels

Question 2

process of osmosis

Answer 2

movement of water by diffusion through selectively permeable membrane from an area of low solute area to high solute area.

Question 3

osmotic pressure

Answer 3

the pressure required to prevent net water/solvent movement (the pressure required to return starting distribution of water before osmosis occurs)

Question 4

hyperosmotic

Answer 4

a solution with a higher osmotic pressure than another

Question 5

isosmotic

Answer 5

two solution with same osmotic pressure

Question 6

hyposmotic

Answer 6

a solution with a lower osmotic pressure than another

Question 7

distribution of fluid in the body 70kg male

Answer 7

• 60% fluid
• 2/3 intracellular
• 1/3 extracellular (20% plasma, 80% interstitial

Question 8

osmolarity

Answer 8

osmotic pressure exerted by a solution across a perfect semipermeable membrane compared to pure water. dependantn on concentration of particles in solution. = molarity x dissociation factor = osmol/L

Question 9

tonicity

Answer 9

the affect of osmotic pressure/osmolarity ont he cell. the capability of a solution to modify the volume of cells by altering their water content. considers the solute concentration and permeability to the membrane

Question 10

hypertonic

Answer 10

a solution with a higher osmotic pressure than another, solute concentration higher outside so water leaves cell causing shrinkage

Question 11

isotonic

Answer 11

two solution with the same osmotic pressure, so no net movement since solute concentration is same on inside

Question 12

hypotonic

Answer 12

a solution with lower osmotic pressure than another. water moves into the cell causing swelling because solute concentration is higher inside cel

Question 13

relative concentrations of Na+

Answer 13

• intacellular fluid: lower (10mM)
• extracellular fluid: higher (142 mM)

Question 14

relative concentrations of K+

Answer 14

• intacellular fluid: higher (140mM)
• extracellular fluid: lower (4mM)

Question 15

relative concentrations of Cl-

Answer 15

• intracellular fluid: lower (4mM)
• extracellular fluid: higher (102mM)

Question 16

electrolyte distribution in body

Answer 16

• NaK ATPase sets up uneven ion distributions
• Na and Cl have high extra cellular concentrations
• K ions have high intracellular concentration

Question 17

kidney absorption

Answer 17

180L/day and the majority is then reabsorbed. some things are secreted back to be removed via urine

Question 18

filtration and urine production

Answer 18

blood via afferent arteriole to glomerulus. filtration into nephrone. most of blood contents filtered

Question 19

absorption and urine production

Answer 19

reabsorption of most things in the renal tubule from tubular fluid into blood. glucose is almos tentirely reabsorbed

Question 20

secretion and urine production

Answer 20

tubular secretion of some things from blood back into tubular fluid so that it can be urinated out. creatine is almsot entirely secreted