What is the process of blood cell production called?
Haemopoiesis
Haemopoiesis occurs in the bone marrow.
What are the most primitive cells in the bone marrow?
Pluripotent haemopoietic stem cells (HSCs)
HSCs differentiate to form all types of blood cells.
What does the prefix “hyper-” mean?
Increased
This prefix is often used in medical terminology.
What does “leucocytosis” mean?
High white cell count
It indicates an increase in the number of white blood cells.
Where is blood primarily made in the body?
Bone marrow
Bone marrow is referred to as the ‘blood factory’.
What are the requirements for blood cell production in the bone marrow?
- Growth factors (cytokines)
- Metals and vitamins
- Stroma (blood vessels, fat, bone)
These elements are crucial for the replication and differentiation of stem cells.
What is the normal lifespan of red blood cells?
120 days
Erythrocytes are generated in the bone marrow.
What is the function of erythropoietin (EPO)?
Regulates red blood cell production
EPO is primarily produced in the kidney.
What is the process of red blood cell production called?
Erythropoiesis
This process occurs in the bone marrow.
What is the lifespan of platelets?
7 – 10 days
Platelets are involved in blood clotting.
What is the process of white blood cell production called?
Granulopoiesis
This process is influenced by cytokines like G-CSF.
What are cytokines?
Cell hormones that regulate blood cell production
They control differentiation and the number of cells produced in the bone marrow.
What is the function of G-CSF?
Controls leucocyte production
G-CSF is a type of cytokine.
How many red blood cells are produced each day?
200 billion
This equates to approximately 20 mL of blood.
What is the function of megakaryocytes in the bone marrow?
Precursor of platelets
Megakaryocytes shed fragments of cytoplasm to form platelets.
What is assessed in a blood count?
- Hb
- Reticulocyte count
- WBC
- Platelets
Blood counts help evaluate haemopoiesis.
What does the term “pluripotent” refer to in the context of stem cells?
Ability to differentiate along all cell lines
Pluripotent stem cells can give rise to all types of blood cells.
What is the first site of blood production during fetal development?
Yolk sac
Blood production later shifts to the bone marrow.
What happens to red marrow as a person ages?
Changes to inactive (fat/yellow) marrow
Red marrow is where active haemopoiesis occurs.
Which organ 1st produces blood cells?
Liver
Which organs/parts produce blood cells in the prenatal stage?
Yolk sac, liver, spleen, bone marrow
Which prenatal month does bone marrow make blood cells?
4th month
Which organs/body parts produce blood cells in the postnatal stage?
Vertebra, sternum, rib, femur, tibia
