Lecture 24: Urinary System - Physiology of the Kidneys, Ureters, and Bladder

Question 1

Firstmost function of the urinary system

Answer 1

Maintain homeostasis

Question 2

Physiology functions of the kidneys

Answer 2

1. Regulate interstitial fluid volume

2. Reabsorb required substances

Question 3

What is osmosis

Answer 3

When water molecules go across a semipermeable membrane and end up with a higher concentration of water molecules. Water in higher concentration puts pressure on the membrane. Membrane lets water pass, but not dissolved solids.

Question 4

What is in the capsule of Bowman?

Answer 4

The glomerulus and its arteriole.

Question 5

What does almost everything in the nephron have to go through?

Answer 5

The glomerular filtrate, a pressure that puts fluid and solutes through holes in the glomerular capillaries.

Question 6

What absorbs important solutes and from where?

Answer 6

The convoluted tubule from the glomerular filtrate.

Question 7

What makes blood colloid pressure (aka BCOP)?

Answer 7

Pressure of proteins and other solids in blood. Total pressure is 30mm Hg versus the arteriole pressure.

Question 8

What is the net filtration pressure

Answer 8

A force that gets the filtrate through the kidneys.

Question 9

Arteriole filters

Answer 9

endothelium, basement membrane, slit membrane

Question 10

Functions of arteriole filters

Answer 10

to filter out large proteins

Question 11

How much blood flow does the kidneys receive

Answer 11

20%

Question 12

How much is filtered a day?

Answer 12

about 200 liters, but 99% is reabsorbed

Question 13

what regulates glomerular filtration?

Answer 13

three mechanisms - renal autoregulation; neural regulation; hormonal regulation - and five control systems.

Question 14

Renal autoregulation

Answer 14

At rest, normal processes.

Question 15

Neural regulation

Answer 15

Increased sympathetic activity; causes the arterioles of the kidney to constrict and to release norepinephrine, and renin

Question 16

Hormonal regulation

Answer 16

Occurs through hormones: angiotensin II, atrial natriuretic peptide (ANP), and aldosterone.

Question 17

What is considered abnormal in urine?

Answer 17

An excretion of glucose. This happens when glucose is produced in larger amounts than the tubules can handle

Question 18

Functions of the descending loop of Henle

Answer 18

Reabsorption of water and large ions and molecules

Question 19

Functions of aldosterone in the loop of Henle

Answer 19

Increase the reabsorption of sodium and water by the principal cells.

Question 20

Function of tubular secretion

Answer 20

Getting rid of unwanted materials in the system; mostly occurs in tubules. When pH is too acidic, H+ ions are removed; HCO3- are increased or decreased as needed to maintain pH.

Question 21

Potassium secretion

Answer 21

Aldosterone increases the secretion by the tubules; increased levels of Na encourage potassium secretion in the DCT. Tubular secretion of K+ increases when there are high serum K+ levels.