Excretion Flashcards
Metabolic waste
Consists of the waste substances that are toxic or produced in excess by the reactions inside cells
Egestion
The removal of undigested food by the process of defecation
Deamination
The removal of the amine group from an amino acid to produce ammonia
Hepatic portal vein
Carries blood from the digestive system to the liver
Kupffer cells
Macrophages that break down and recycle old red blood cells
Bilirubin
Waste product from break down of Haemoglobin
Urea
Excretory product formed from break down on excess amino acids
Ornithine cycle
The process in which ammonia is converted into urea.
Detoxification
Conversion of toxic molecules to non toxic molecules
Nephron
Receives fluid from blood capillaries and converts into urine
Glomerulus
Capillaries that increase blood pressure to squeeze fluid out of the body.
Selective reabsorption
When useful substances are reabsorbed from the nephron into the blood stream
Afferent vessels
Bring blood into organ
Efferent vessels
Carry blood away from the organ
Ultrafiltration
Large molecules and cells left in blood and small molecules pass through Bowman’s capsule
Podocytes
Specialised cells that make up lining of Bowman’s capsule
Microvilli
Microscopic folds that increase the surface area of the cell
Co-transporter proteins
Proteins in the cell surface membrane that allow facilitated diffusion of simple ions with a larger molecule
Facilitated diffusion
Diffusion that is enhanced by the actions of proteins in the plasma membrane
Sodium-potassium pumps
Special proteins in plasma membrane that actively transport sodium and potassium ions against their concentration gradients
Hairpin countercurrent multiplier
Allows exchange between contents to create high concentration solutes
Osmoregulation
Control and regulation of water potential of body fluids
Distal convoluted tubule
Coiled portion of the nephron between loop of Henle and the collecting duct
Antidiuretic hormone (ADH)
Increases reabsorption of water
