Haematopoiesis Flashcards
What are all blood cells derived from?
Haematopoietic stem cells (hemocytoblasts)
What are platelets? What do they play a role in?
Cell fragments
Clot formation
How long do RBCs circulate in the body for?
120 days
In what 3 parts of the body are there notable haematopoietic sites?
Liver, spleen and bone marrow
Give two adaptations of RBCs to their function.
1) Biconcave shape, lipid bilayer –> flexible through capillaries
2) No organelles/nucleus, maximum space for Hb
What is the composition of blood in percentage terms?
55% plasma
45% RBCs
(Less than 1% is leukocytes/platelets)
Name 5 leukocytes (WBCs)
Basophils Eosinophils Monocytes (Macrophages) Neutrophils Lymphocytes
When is a monocyte a macrophage?
When it is in the tissues and not the blood
Which WBCs are the first line killers of the innate immune system?
Eosinophils
Neutrophils
Basophils
Monocytes/macrophages
What do NK cells do?
Kill cells, by stimulating them to perform apoptosis
How do platelets help in clot formation?
They act as the initial primary plug and as a surface for clotting factors to make the final fibrin clot
How can blood cells be assessed?
Full blood counts
Blood films
What is the term given to a particularly high RBC count?
Polycythemia
What is the term given to a particularly high WBC count?
Leukaemia
What is the term given to a particularly high platelet count?
Thrombocythemia
