1. URINE FORMATION NOTES are on a Smartboard Slide separate from this powerpoint. Continue with notes….

3. Important chemicals in the urinary system
Juxtaglomerular Apparatus- .where the DCT meets the Aff. Arteriole
The cells in these 2 locations are special
Cells secrete an enzyme - (Renin), in response to an individual’s drop in blood pressure.

5. Renin stimulates a conversion of hormones from the liver and lungs.
Angiotension II is produced and is a vasocontrictor that increases BP
Stimulates Aldosterone [adrenal glands] and ADH [pit gland]

7. Aldosterone tells the DCT and Collecting Duct to reabsorb Na+.
It follows that when Na+ is reabsorbed into the blood, H20 will follow, increasing Blood volume, and thus, blood pressure.

8. ADH works with aldosterone.
ADH makes the cells of the collecting duct and DCT more permeable to H20 for reabsorption.
Water moves from tubules to capillaries, resulting in increased blood volume and increased blood pressure

9. Ureters, BLADDER and Urethra
Ureters – paired tubes from hilus to bladder
Enter underside of bladder. – 1-way valve
3-layered wall - middle is smooth muscle.
Urinary Bladder – hollow muscular organ (500 ml capacity – can stretch to hold 2X as much)
Trigone - region of three openings – 2 ureters and 1 urethra
4-layered wall – detrusor muscle – smooth muscle layer

12. Urethra – muscular tube – longer in males
internal urethral sphincter - at junction of bladder and urethra – involuntary (smooth muscle)
external urethral sphincter – voluntary – skeletal muscle
urination – voiding the bladder, micturition