The process in which metabolic waste is removed from an organism.
Wastes produced by working cells. (cellular waste)
What role does the skin play in excretion?
-The sweat glands excrete water, salts, and urea from the blood in the form of
Sweating is the body’s way of cooling down =Thermoregulation Normal body Temperature is 98.6°F
Function:
Wastes: -Sweat (water, mineral salts, urea)
Outer layer of skin
Inner layer of skin
Regulate body temperature
Sweat excretes through
Responsible for perspiration and maintaining body temperature
Release oils that keep skin and hair soft
What is the liver’s role in excretion?
-Recycles worn out red blood cells (RBC) -Produces urea by breaking down amino acids (Moderately toxic)
Function:
The process of converting toxic chemicals into harmless chemicals.
Ex: Alcohol An alcoholics liver MUST work harder!!!!
Wastes: Urea and worn out RBC
What is urea?
-Your body changes amino acids into: -ammonia (poisonous) -pyruvic acid (used as energy source) -glycogen (stored fat)
Since ammonia is toxic, your liver MUST change it into UREA (less toxic)
Urea is then filtered out of the blood by the
What is the role of the kidneys in excretion?
Function:
-Filtration of wastes from blood -Reabsorption of water and nutrients (maintains water balance)
Wastes: Urine
How is blood “cleaned”?
Renal Arteries: Carry blood AWAY from body to kidneys
Kidneys: Main organ. Salt and water maintained, wastes removed (urine) (filtering unit of kidneys- nephron)
Ureter: Tubes that urine passes through to get to the urinary bladder.
Urinary bladder: Temporarily stores urine
Urethra: Urine excreted out of the body
Renal Veins: Carry “cleaned” blood back to body
What is the role of the lungs in excretion?
Function:
-Gas Exchange -Oxygen in, CO2 out
Wastes: CO2, water vapor
Filtering Unit: Alveoli (air sacs) -gas exchange occurs here
-Inflammation of kidney (nephron not working-NO Filters) Caused by: Bacterial infection
Treatment: Antibiotics
Long Term Effects: Can lead to kidney failure if untreated
-Mineral calcium buildup in kidney
Caused by: No known Cause (although believed poor diet plays a role)
Treatment: Surgery or shock waves
Long Term Effects: Very painful. May become recurring
-Painful inflammation of affected joints (usually big toe and ankle bone) due to crystallizations of uric acid
Caused by: High levels of uric acid in blood (solid nitrogenous waste) (found in red meat, alcohol) Treatment: Lots of water, special diet, and medication Long Term Effects: Very painful. Occasional Flair ups.
-Fats accumulate in the liver scarring cells
Caused by: -Too much alcohol -Hepatitis B
Treatment: No cure. Must change habits. Damage irreversible.
Long Term Effects: The liver stops working. Homeostasis no longer maintained. Can be fatal
-inflammation of the liver
Caused by: virus
Treatment: No Cure. Maintained By medication and diet
Long Term Effects: May lead to cirrhosis and liver failure. Can be fatal.
Why do doctors test urine? Possible urinalysis results may be an indication of:
1. Color/Odor may indicate: Dark Brown: Liver Disorder Red/Pink: Blood Dark Yellow/Orange: B Vitamins, Carotene Green/Blue: Artificial Coloring Foamy: Proteinuria
2. pH
3. Glucose
4.Proteins: + may indicate blood in urine or kidney disease 5. Drug Tests 6.Pregnancy Test- Human Chorionic Gonadatrophin (HCG) detected in urine