Transcript Excretory System

Excretory System
Getting the waste out
Excretory system organs
A.
Kidney’s
1. Cortex
2. Medulla
3. Pelvis
B. Lungs
C. Liver
D. Skin
Urinary System
A. Kidney’s – create urine by filtering the blood
B. Ureters – carry urine from kidney to urinary
bladder
C. Urinary bladder – stores urine
D. Urethra – tube emptying the urinary bladder
Urine Composition
Nephron
• Glomerulus
• Bowman’s Capsule
• Proximal Convoluted
Tubule
• Loop of Henle
• Distal Convoluted
Tubule
• Collecting Duct
Nephron Component Functions
• Glomerulus: mechanically filters blood
• Bowman's Capsule: mechanically filters blood
• Proximal Convoluted Tubule: Reabsorbs 75% of the
water, salts, glucose, and amino acids
• Loop of Henle: Countercurrent exchange, which
maintains the concentration gradient
• Distal Convoluted Tubule: Tubular secretion of H
ions, potassium, and certain drugs.
Nephrons
• Functional unit of the kidney that makes urine,
controls water balance, & regulates blood pressure
• Filters 45 gallons of blood/day making 1 ml of
urine/min
• Nephron FXN’s…Filtration, Reabsorption, &
Excretion
Kidney Functions
(All occur in NEPHRONS 1,250,000 / kidney)
Filtration - High pressure at the glomerulus
filters:___ out of the blood into the filtrate
a. Water
b. Glucose
c. Salts
d. Amino Acids
e. Urea
Kidney Functions
(All occur in NEPHRONS 1,250,000 / kidney)
Reabsorption (From filtrate) – Loop of Henle
99% water (178 liters/day)
100% glucose (180 g/day)
91% salts (1 300 g/day)
100% amino acids
50% urea
Kidney Functions
(All occur in NEPHRONS 1,250,000 / kidney)
Secretion (From blood stream to the distal tubule)
- Uric acid
- Creatine
- H+
- Ammonia
Kidney Functions
(All occur in NEPHRONS 1,250,000 / kidney)
Excretion (Collecting ducts carry urine toward ureters)
a.
Water
b. Salts
c.
Uric acid
d.
Urea
e.
Ammonia
f.
Creatine
Excretion
•
•
Lungs
a.
CO2 (From aerobic respiration)
b.
Water (From dehydration synthesis
reactions)
Liver
A. Detoxification center
• a. Destroys worn out Red Blood Cells, Gives urine
the yellow color
• b. Breaks down excess amino acids forming urea
• c. Removes bacteria, certain drugs, and
hormones from the blood and inactivates or
changes them to a less poisonous form (e.g.
alcohol).