Haemaglobin metabolism Flashcards
When does the switch from foetal to adult haemoglobin occur?
3-6 months of age
Where does the breakdown of haemaglobin occur?
In phagocytes of the reticuloendothelial system
What is haemaglobin broken down into?
Haem
Globin
What is haem broken down into?
Bilirubin
What is globin broken down into?
Its constituent amino acids
What does the phagocyte do with the bilirubin?
Extrudes it into the blood
Where is bilirubin transported to? How?
Transported in the blood
to the liver
What does the liver do with bilirubin?
Secretes it with bile
into the intestines
What happens to bilirubin in the intestines?
Bacteria in colon metabolise it to urobilinogen
What happens to urobilinogen in the intestines?
Oxidised to stercobilin
Some is reabsorbed into blood
What happens to stercobilin in the small intestines? How does this show?
Excreted in faeces
Makes faeces a brown colour
What happens to the urobilinogen that’s reabsorbed into blood? How does this show?
Transported in blood to kidneys
excreted in urine
Makes urine yellow colour
What does excess red blood cell destruction lead to?
Excess bilirubin formation
excess bilirubin in the blood
gives jaundice
What is jaundice?
Yellowing of the skin and sclera
