Lecture 1 - Introduction to haematology and blood tests Flashcards
(30 cards)
What are the main components of blood?
Plasma (~55%) and blood cells (~45%).
What are the three major types of blood cells?
Red blood cells (erythrocytes)
white blood cells (leukocytes),
platelets (thrombocytes).
What is the function of red blood cells (RBCs)?
Oxygen transport to tissues and removal of carbon dioxide.
What is the typical lifespan of a red blood cell?
90–120 days.
Name two growth factors essential for red blood cell and platelet production.
Erythropoietin (EPO) for red blood cells
thrombopoietin (TPO) for platelets.
Which white blood cells are part of the innate immune response?
Neutrophils
monocytes, eosinophils, and basophils.
What is the primary function of lymphocytes?
Adaptive immunity, including antigen-specific responses and memory.
What is the function of platelets?
Platelets mediate blood clotting and vessel repair.
How do neutrophils help fight infection?
By engulfing and digesting microbes through phagocytosis.
What is the role of monocytes once they migrate into tissues?
They differentiate into macrophages or dendritic cells for phagocytosis and antigen presentation.
Where does haematopoiesis primarily occur in adults?
In the bone marrow.
What is a haematopoietic stem cell (HSC)?
A multipotent stem cell capable of self-renewal and differentiation into all blood cell types.
What proportion of the bone marrow is dedicated to white cell and red cell production?
75% for white cells and 25% for red cells.
What regulates the production of neutrophils?
Granulocyte colony-stimulating factor (G-CSF).
What is erythropoietin (EPO), and when is it produced
A hormone produced by the kidneys in response to hypoxia or anaemia to stimulate red blood cell production.
What are haematopoietic growth factors, and how do they function?
Glycoprotein hormones that regulate blood cell proliferation, differentiation, and survival through receptor-mediated signalling pathways.
What does the full blood count (FBC) measure in red cells?
Haemoglobin (Hb) concentration, red cell count, haematocrit (Hct), MCV, MCH, and MCHC.
Which parameters of the FBC are related to white cells?
Total white cell count and differential counts (e.g., neutrophils, lymphocytes, monocytes).
What does the FBC measure for platelets?
Platelet count, typically within the range of 150–400 x 10⁹/L
What is the normal range for haemoglobin in males and females?
Males: 135–180 g/L; Females: 115–160 g/L.
Why is the mean cell volume (MCV) important in anaemia diagnosis?
It helps classify anaemia as microcytic (<80 fL), normocytic (80–100 fL), or macrocytic (>100 fL).
What is a reticulocyte?
An immature red blood cell recently released from the bone marrow.
How are reticulocytes identified on a blood film?
They appear larger and bluer than mature red cells (polychromasia).
What does a high reticulocyte count indicate in anaemia?
Increased red blood cell production, often due to haemolysis or acute blood loss.
