1. NOTES UNIT 9 part 1: Urinary (Excretory) System Anatomy of the Urinary System

2. Urinary (Excretory) System…
*The urinary system consists of the kidneys, ureters, urinary bladder, and urethra.

3. Functions of the Urinary System:
remove salts and nitrogenous wastes from the blood
N wastes are from protein metabolism
2) maintain normal water and electrolyte concentrations within body fluids
*includes blood volume
3) Helps regulate pH of blood
4) Helps regulate red blood cell production

4. ORGANS OF THE URINARY SYSTEM
KIDNEYS: remove substances from the blood; form urine
2) URETERS: transport urine from the kidneys
3) URINARY BLADDER: stores urine
4) URETHRA: conveys urine to the outside of the body

5. ● KIDNEYS located high on the posterior abdominal wall
 each kidney is divided into the:
*CORTEX: outer region
*MEDULLA: inner region
*PELVIS: funnel-shaped region where superior end of ureters expands

6. KIDNEY FUNCTIONS:
remove metabolic wastes from the blood & combine them with water  formation of urine
Only need to have 1 functioning kidney
If kidneys aren’t functioning, must go through dialysis
2) secrete hormone erythropoietin  control of red blood cell formation
3) involved in activation of vitamin D

7. *when low oxygen levels are detected by brain, kidneys release hormone into blood
*hormone will bind to red bone marrow cells and cause them to make more red blood cells
*the kidney is the last step needed to convert sunlight into usable Vitamin D

8. KIDNEY BLOOD SUPPLY:
• RENAL ARTERIES: arise from abdominal aorta; supply blood to kidney
 branches into smaller arteries & eventually into the AFFERENT ARTERIOLES
• blood returns to the inferior vena cava through the RENAL VEINS

9. *so you can see how multiple systems interact and work together.
You eat protein which is digested.
Amino acids are absorbed across villi into capillaries (mesenteric).
Blood routes through liver and then returns to right side of the heart
Blood goes to lungs to get oxygen & get rid of carbon dioxide
Blood returns to left side of the heart
Blood with nitrogen waste products in it leaves the heart through aorta
Blood goes through renal arteries to kidneys to be filtered
Nitrogen waste product ends up in urine to be excreted

10. ● URETERS each ureter is about 25 cm long
 begin at the renal pelvis; extend downward and join the URINARY BLADDER from underneath

11. (forms due to an imbalance in a mineral, such as calcium)
**Kidney stones may form in the renal pelvis and be passed through a ureter
(forms due to an imbalance in a mineral, such as calcium)
TREATMENTS:
Small stones:
Drinks lots of water
Pain relievers (need to pass the stones- OUCH!)
Medicines to relax ureter muscles
Large stones:
Use sound waves to break up the stones (now can pass them)
Surgery to remove stones

12. ● URINARY BLADDER
a hollow, distensible (“stretchable”), muscular organ
 stores urine and forces it into the URETHRA

13. ● URETHRA  conveys urine from the urinary bladder to the outside
 in females, urethra opens just anterior to the vaginal opening
 in males, urethra is enclosed in the penis
urethra
anus
*easier for bacteria to get to female urethra; ALWAYS wipe front to back to avoid bringing bacteria towards urethra

14. ● URETHRA
*female urethral pathway is shorter than in males; as a result, females are more prone to urinary tract infections (UTI)
(“CYSTITIS” =
inflammation of
the urinary bladder)

15. *If bacteria have entered urethra and moved up into bladder, it can cause pain during urination and it may feels like you urgently need to urinate but you don’t have to.
*Since it is bacterial, got to doctor for antibiotics & can take over the counter medicine to help numb the bladder: AZO (will turn urine orange)