Excreation As An Example Of Homeostatic Control Flashcards
What is excretes through the skin?
Salts, urea, water, uric acid and ammonia
Excretion
The removal of metabolic waste from the body
Metabolic waste
A substance that is produced in excess by the metabolic processes in the cells; may be toxic.
How are amino acids processed?
Toxic amino group is removed (deamination) it initially forms ammonia but is quickly converted into urea. The remaining keto acid can release energy.
What vessels are connected to the liver?
The hepatic artery
The hepatic portal vein
The hepatic vein
The hepatic artery
Oxygenated blood from the heart travels from the aorta. This gives the liver cells the energy they need to function.
The hepatic portal vein
Deoxygenated blood from the digestive system enters the liver. The blood is rich in the products of digestion.
Structure of the liver
Arranged so the greatest possible contact between the blood and the liver cells. Divided into lobes and cylindrical lobules.
What is the sinusoid
The chamber in which the mixed blood from the artery and portal vein flow through.
This is where the liver removes substances from the blood.
What are kupffer cells?
Macrophages which move about within the sinusoid.
They break down and recycle old red blood cells.
What is bile?
A product of haemoglobin breakdown bilirubin is a bile pigment.
Bile is transported to the gall bladder.
