Nephron and Renal Overview

Question 1

What are the two types of nephrons?

Answer 1

cortical and juxtamedullary

Question 2

What are the 4 processes of the nephron?

Answer 2

filtration, reabsorption, secretion, excretion

Question 3

What does the proximal tubule reabsorb?

Answer 3

2/3 of sodium, potassium, and water; all glucose and amino acids; most bicarb; half of urea

Question 4

What does the proximal tubule secrete?

Answer 4

H+, drugs, pollutants, and para-amino hippurate (PAH)

Question 5

What is reabsorbed in the descending loop?

Answer 5

water

Question 6

What is reabsorbed in the ascending loop?

Answer 6

solutes (NaCl)

Question 7

What is the osmolality at the beginning, bottom, and end of the loop of Henle?

Answer 7

isosmotic, hyperosmotic, hyposmotic

Question 8

What is reabsorbed in the early distal tubule?

Answer 8

Na+. No water

Question 9

What is reabsorbed in the collecting duct?

Answer 9

ions and water

Question 10

What hormones control reabsorption in the collecting duct?

Answer 10

ADH, aldosterone, ANP

Question 11

What specialized cells make up the juxtaglomerular appartus? What is their location?

Answer 11

macula densa (distal tubule), extraglomerular mesangial cells (middle of JGA), juxtaglomerular/granular cells (afferant arteriole)

Question 12

What is the purpose of the juxtaglomerular cells?

Answer 12

secrete renin

Question 13

What are the signals for renin release?

Answer 13

increased sympathetic activity, low NaCl in the macula densa, low BP (low stretch in JG cells)