Excretion Flashcards
What is excretion?
Process of removing metabolic waste products from the body
What are some examples of waste products from the body in excretion?
-Co2 produced in respiration
-Bile pigment produced during breakdown of Hb
-Nitrogenous waste produced during breakdown of Amino Acids
What is the liver?
-Major body organ involved in homeostasis
-Fast growing and regenerates
How does the liver work?
Has a rich oxygen supply which oxygenated blood supplied to liver by hepatic artery and removed and returned to the heart by the hepatic vein
-Also supplied blood by hepatic portal vein (deoxygenated)- blood with products of digestion from intestines
Why do we get rid of metabolic waste products?
They can alter the PH, interfering with cell processes so normal metabolism is effected
Why is excess co2 a problem?
Transported as Hydrogen Carbonate Ions, releases H+ ions that affect the pH of the cytoplasm of RBC. Changing bonds and shape of Hb reducing affinity for oxygen
Why must we secrete nitrogenous compounds?
Amino acid’s can’t be stored as they contain a toxic amino group which needs removing
What is the bile duct?
Duct that carries the bile secreted in liver to gall bladder
How is liver further divided from lobes?
Into lobules
In what blood vessel does blood from vein and artery mix?
A sinusoid
What’s the purpose of blood passing through the sinusoids?
Put blood in close contact with liver cells that alter the conc of substances in it
What do kupfer cells in sinusoids do?
Recycle and break down RBCS producing bilirubin as well
What vessel drains blood from the liver?
Hepatic vein
What are liver cells called?
Hepatocytes
What are the metabolic functions of hepatocytes?
Protein synthesis
Transformation and storage of carbs
Synthesis of cholesterol
Detoxication
