Flashcards in Introduction to Haematology Deck (56)
What is blood?
A specialised fluid composed of cells suspended in a liquid
What is the liquid that blood cells are suspended in?
Name the 3 different cells found in blood.
* Red blood cells
* White blood cells
Name the 3 main functions of blood.
* Fight infection
* Transport oxygen
* Prevent bleeding
Haemopoiesis/Haematopoiesis is the ....?
Production of blood cells
What are blood cells derived from?
A relatively small pool of pluripotent stem cells capable of making all the different types of blood cells
What are pluripotent stem cells?
An immature stem cell which is capable of giving rise to several different cell types
In the embryo, where does haematopoiesis occur?
* Yolk sac then liver then marrow
* 3rd to 7th month – spleen
At birth, where does haematopoiesis occur?
Mostly bone marrow, liver and spleen when needed
Between birth and maturity, where does haematopoiesis occur?
Number of actives sites in bone marrow decreases but retain ability for haematopoiesis
When bone marrow stops making blood cells, what organ takes over?
The spleen takes over
As an adult, where does most haemoatopoiesis occur?
Bone marrow of skull, ribs sternum, pelvis, proximal ends of femur
Where, in the skeleton, is most bone marrow found?
Via what 2 processes do stem cells make blood?
Proliferation + Differentiation
Describe the differentiation stage in the development of blood cells from stem cells.
Development of the features of the specialised end cell population from stem cell
To be a stem cell, what must a cell be able to do?
Outline the process of maturation of a neutrophil.
3. Metamyelocyte forms
4. Band forms
5. Neutrophils (in blood)
What is smaller, a daughter cell or a parent cell?
What is erythropoiesis?
Production of red blood cells
What is a Pronormoblast?
The first cell in the production of a RBC
What is a Reticulocyte?
The second last cell in the development on an RBC which is the first found in the circulation and not the bone marrow
A reticulocyte loses some volume and the minor remnants of RNA degrade for it to become a mature red cell/erythrocyte
What is a Megakaryocyte?
A big cell with lots of nuclei in it (never seen in the blood stream as they are too big)
Instead of the cytoplasm dividing, it remains the same but with lots of nuclei
Name the 2 main roles of RBC's.
* Carry oxygen
* Other roles e.g buffer CO2
What is the main function of platelets?
To stop bleeding
What are the 2 main functions of WBC's?
* Fight infection
* Others e.g. cancer prevention
What are granulocytes?
A category of white blood cell characterised by granules in the cytoplasm
How can granules in granulocytes be seen?
What are granulocytes named according to?
They are named according to their uptake of stains when originally identified (eosin and basic dyes)