B6 Haematology 1 Flashcards
What is plasma made of?
water (90%), electrolytes, glucose, lipids, metabolites, gases, hormones, drug and plasma proteins?
What are the 3 plasma proteins and their roles?
albumins- transport, colloidal osmotic pressure
globulins- transport, clotting, precursors to hormones (angiotesinogen), defence
fibrinogen- clotting
What is serum?
coagulated plasma
Do red blood cells have a nucleus and what is its shape?
no nucleus, RBCs are discoid
What is the life span of RBCs?
120 days
Why is control of erythropoiesis essential?
to maintain RBC level
What controls erythropoiesis?
erythropoietin (polypeptide hormone)
Hoe does erythropoietin work?
released by peritublar cells in the kidney and increases the number of stem cells committed to erythropoiesis
What are immature RBCs?
nucleus is extruded and taken up by bone marrow macrophages
What does mRNA in reticulocyte allow?
haemoglobin to be synthesised
What happens to the retic count when erythropoiesis is increased?
increases
What is the structure of haemoglobin?
2 components: haem & globin
tetrameric: 4 globin chains made of polypeptide with haem prosthetic group
What is haem?
ferrous iron (Fe2+) at the centre of a protoporrphyrin complex
How are global chains linked?
non-covalent bonds
What subunits do adult and foetal haemoglobin contain?
adult - 2 alpha2, 2 beta2
foetal - 2 alpha2, 2 gamma2
How do we get iron from our diet?
ferrous iron Fe2+ (Fe3+ reduced to Fe2+ in stomach)
Fe3+ produced by mucosal cells of duodenum, binds to apoferritin to produce ferritin
release iron into blood to bind with transferrin
delivers iron to bone marrow
iron in Hb
What are the 5 leucocytes?
neutrophils eosinophils basophils monocytes lymphocytes
What is the role of neutrophils?
phagocytosis of microorganisms
What is the role of eosinophils?
associated with parasite killing and inflammation
What is the role of basophils?
release histamine in hypersensitivity reactions
What is the role of Monocytes?
phagocytic, leave blood and become macrophages
What is the role of lymphocytes?
produce antibodies
What do phagocytes comprise of?
neutrophils, eosinophils, basophils (all called granulocytes) and monocytes
What do immunocytes comprise of?
lymphocytes?
