Haemopoiesis Flashcards
Define Haemopoiesis:
This is the formation of blood cells
What are the different groups of white cells?
Granulocytes
Monocytes
Lymphocytes
List the different types of granulocytes:
Neutrophils
Eosinophils
basophils
What do monocytes become?
Macrophages - once the enter the tissue
What are the different types of lymphocytes?
B cells
T cells
Natural Killer Cells
What is the lifespan of a RBC?
120 days
What is the lifespan of a neutrophil?
7-8 hours
What is a platelet precursor known as?
Megakaryocyte
What are the precursors to white blood cells?
Blasts
erythro/myelo
What is the name for the nucleated precursor between a blast and a neutrophil?
Myelocytes
Where are blasts found?
Bone marrow
What comes first in the production of blood cells?
Long term haemopoietic stem cells
Then
Short term haemopoietic stem cells
Which stem cell is able to self renew more?
Long term
Define proliferation:
An increase in numbers
When has bone marrow developed in untero?
Week 16
In adults where does haemopoiesis occur?
The marrow within the axial skeleton, pelvis and proximal long bones
What are sinuses in bone marrow?
These are where arterioles drain into as opposed to venules
The are larger and have a discontinuous basement membrane
How do formed blood cells leave the bone marrow?
Through the fenestrations of the endothelial cells
What is RBC release associated with?
Sinusoidal dilation and increased blood flow
What cells ctively migrate towards the sinusoids?
Neutrophils
How do megakaryocytes come into contact with the sinusoids?
They extend long branching processes known as proplatelets
What is red marrow?
Bone marrow which is haemopoeitically active
What is yellow marrow?
Fatty inactive marrow which increases as you age
What regulates the maturation of neutrophil precursors?
Granulocyte colony stimulating actor
G-CSF
