Excretory System Flashcards
What is excretion
Removal of metabolic wastes from the body
What is deamination?
The breakdown of amino acids in the liver
Describe deamination
- Removal of amino group from the amino acid
- Amino group is converted to ammonia
- Ammonia converted to urea (toxicity)
- Urea moved to kidneys via blood for excretion
What is tubular secretion and where does it occur
Fluid is forced out of the blood and collected by glomerular capsule, fluid now called filtrate.
Location: renal corpuscle
(glomerulus & glomerular capsule)
What does the filtrate consist of??
Salt
Amino acids
Water
Vitamins
Urea
Glucose
What is selective reabsorption and where does it occur?
Reabsorb useful substances from filtrate back into the blood
What materials are absorbed in selective reabsorption?
Water
Ions
Glucose
Amino acids
What is tubular secretion and where does it occur?
Adds substances from the blood into the filtrate
Location: distal convoluted tubule
What substances are involved in tubular secretion?
Potassium
Hydrogen
(ions)
Creatine
Drugs - penicillin
Where is glucose stored?
It’s converted to glycogen and stored in liver
What is ammonia?
A toxic waste product of deamination
What is the purpose of excretion?
If wastes accumulate in the body they become toxic and affect the body’s ability to function (homeostasis)