Ch. 14 - Renal, Fluid, and Acid-Base Physiology

Question 1

How does the total body water break down?

Answer 1

• 60% of total body weigh = total body water
• Intracellular fluid = 2/3 TBW
• Extracellular fluid = 1/3 TBW
  
  • Interstitial fluid = 75% of ECF
  • Plasma = 25% of ECF

Question 2

What is the Fluid Movement formula?

Answer 2

Fluid movement = k [(Pc+πi) - (Pi+πc)]

Question 3

How is nephrotic syndrome defined?

Answer 3

By > 3.5g of protein in urine per day

Question 4

What can cause edema?

Answer 4

• High capillary pressure (Cirrhosis)
• Low capillary oncotic pressure (Nephotic syndrome)
• High interstial oncotic pressure (elephantitis)
• Increased capillary permeability
• Inappropriate renal sodium and water retention

Question 5

What is an isoelectric point?

Answer 5

The pH where the number of positive charges = the number of negative charges

Question 6

What is it called when at physiological pH amino acids have both a negatively charged carboxyl group (COO-) and a positively charged amino group (NH3+)?

Answer 6

Zwitterion

Question 7

What is the major buffer in extracellular fluid, blood?

Answer 7

Sodium bicarbonate

Question 8

What are the ways that reabsoprtion can occur?

Answer 8

• Active transport
• Facilitated diffusion
• Solvent drag

Question 9

Where is glucose and sodium primarily reabsorbed in the kidney?

Answer 9

In the proximal convoluted tubule

Question 10

What is the basis of the countercurrent multiplier system on the nephron?

Answer 10

Reabsorption of NaCl and impermeability to water of the thick ascending loop

Question 11

How do you calculate the effective renal plasma flow?

Answer 11

Use PAH (paraaminohippuric acid) - it is completely secreted into the proximal tubule and excreted in the urine

Question 12

What does angiotensin II do for the kidney?

Answer 12

When there is decreased renal blood flow, it is formed as aldosterone is released and it causes the efferent arteriole to constrict increasing the glomerular hydrostatic pressure making GFR go back to normal

Question 13

How is GFR primarily regulated?

Answer 13

By changing the resistance (diameter) of the AFFERENT arteriole

Question 14

What is GFR determined by?

Answer 14

• Hydrostatic pressures (Bowman’s space and glomerulus)
• Oncotic (colloid) pressures (Bowman’s space and glomerulus)
• Capillary filtration coefficient

Question 15

How do you calculate GFR?

Answer 15

• Using Cr of inulin clearance
• Freely filtered, no reabsorbed, minimally secreted into urine

Question 16

What substances are freely filtered by the glomerulus, not secreted or absorbed?

Answer 16

Cr and Inulin