Components of blood Flashcards
Blood cells are produced in the ____________ by a process known as haematopoiesis (or hematopoiesis or hemopoiesis)
Blood cells are produced in the bone marrow by a process known as haematopoiesis (or hematopoiesis or hemopoiesis)
All the different blood cell types are derived from a relatively small pool of precursor cells called…
Haematopoietic stem cells
What is the site of haematopoiesis in the embryo?
In the yolk sac
From 2 – 5 months gestation, in liver and spleen before finally establishing in the bone marrow from 5 months
What is the site of haematopoiesis at birth?
Mostly marrow, but liver and spleen when needed
As we grow, active marrow sites decrease but retain the ability. Active marrow is confined to ___________ eventually
Axial skeleton (skull, ribs, vertebrae, pelvis and proximal long bones)
Most stem cells sit in a ____________ state
Quiescent
In granulopoiesis, a myeloid lineage committed blast cells divide and mature through a number of intermediate stages (promyelocyte, myelocyte, metamyelocyte) to become a…
Mature neutrophil
An erythroid committed blast cell (____________) which goes through divisions with proliferation and maturation
to eventually form a mature erythrocyte
An erythroid committed blast cell (pronormoblast) which
goes through divisions with proliferation and maturation
to eventually form a mature erythrocyte
How is thrombopoiesis (platelet formation) different from other cells?
When the blast cells divide the cytoplasm does not, so an
increasing number of nuclei accumulate in a single cell
with a very large cytoplasm. The edges of which buds off to
form platelets that are released into the bloodstream.
In Eosinophils the granules take up ______ which is red and acidic
In Eosinophils the granules take up eosin which is red and acidic
In Basophils the granules take up ___________ dyes which are densely blue
In Basophils the granules take up basic (alkali) dyes which are densely blue
In Neutrophils the granules are ______ and ____________
In Neutrophils the granules are fine and ‘neutral’ mix of the two colours
What are the functions of neutrophils?
Phagocytosis
Granule release for elastases and attract other cells via small molecules released
‘Body stress’ eg bacterial infection, trauma, infarction
What are the functions of eosinophils?
Parasitic infections
Hypersensitivity (allergic) reactions
Segmented nucleus
Neutrophils
Bilobed nucleus
Eosinophil
Large deep purple cytoplasmic granules often obscuring the nucleus
Basophil
In basophils, granules contain ___________ and ___________ like molecules
In basophils, granules contain histamine and heparin like molecules
Function of basophils
Mediates hypersensitivity reactions IgE mediated histamine release (?)
Large single nucleus
Monocytes
Monocytes circulate for about a week then enter tissues to become specialised tissue ____________, so much longer lived than ____________
Monocytes circulate for about a week then enter tissues to become specialised tissue macrophages, so much longer lived than neutrophils
Function of monocytes
Clearing debris, engulfing and destroying infective organisms, and presenting antigen to immune cells and releasing signals to attract other cells
How do mature lymphocytes look like?
Small with condensed nucleus and limited cytoplasm
How do acticated/atypical lymphocytes look like?
Large with plentiful blue cytoplasm often extending up to neighbouring red cells on a blood film and with a larger less condensed looking nucleus
