Lecture 1 - Introduction to haematology and blood tests

Question 1

What are the main components of blood?

Answer 1

Plasma (~55%) and blood cells (~45%).

Question 2

What are the three major types of blood cells?

Answer 2

Red blood cells (erythrocytes)

white blood cells (leukocytes),

platelets (thrombocytes).

Question 3

What is the function of red blood cells (RBCs)?

Answer 3

Oxygen transport to tissues and removal of carbon dioxide.

Question 4

What is the typical lifespan of a red blood cell?

Answer 4

90–120 days.

Question 5

Name two growth factors essential for red blood cell and platelet production.

Answer 5

Erythropoietin (EPO) for red blood cells

thrombopoietin (TPO) for platelets.

Question 6

Which white blood cells are part of the innate immune response?

Answer 6

Neutrophils
monocytes, eosinophils, and basophils.

Question 7

What is the primary function of lymphocytes?

Answer 7

Adaptive immunity, including antigen-specific responses and memory.

Question 8

What is the function of platelets?

Answer 8

Platelets mediate blood clotting and vessel repair.

Question 9

How do neutrophils help fight infection?

Answer 9

By engulfing and digesting microbes through phagocytosis.

Question 10

What is the role of monocytes once they migrate into tissues?

Answer 10

They differentiate into macrophages or dendritic cells for phagocytosis and antigen presentation.

Question 11

Where does haematopoiesis primarily occur in adults?

Answer 11

In the bone marrow.

Question 12

What is a haematopoietic stem cell (HSC)?

Answer 12

A multipotent stem cell capable of self-renewal and differentiation into all blood cell types.

Question 13

What proportion of the bone marrow is dedicated to white cell and red cell production?

Answer 13

75% for white cells and 25% for red cells.

Question 14

What regulates the production of neutrophils?

Answer 14

Granulocyte colony-stimulating factor (G-CSF).

Question 15

What is erythropoietin (EPO), and when is it produced

Answer 15

A hormone produced by the kidneys in response to hypoxia or anaemia to stimulate red blood cell production.

Question 16

What are haematopoietic growth factors, and how do they function?

Answer 16

Glycoprotein hormones that regulate blood cell proliferation, differentiation, and survival through receptor-mediated signalling pathways.

Question 17

What does the full blood count (FBC) measure in red cells?

Answer 17

Haemoglobin (Hb) concentration, red cell count, haematocrit (Hct), MCV, MCH, and MCHC.

Question 18

Which parameters of the FBC are related to white cells?

Answer 18

Total white cell count and differential counts (e.g., neutrophils, lymphocytes, monocytes).

Question 19

What does the FBC measure for platelets?

Answer 19

Platelet count, typically within the range of 150–400 x 10⁹/L

Question 20

What is the normal range for haemoglobin in males and females?

Answer 20

Males: 135–180 g/L; Females: 115–160 g/L.

Question 21

Why is the mean cell volume (MCV) important in anaemia diagnosis?

Answer 21

It helps classify anaemia as microcytic (<80 fL), normocytic (80–100 fL), or macrocytic (>100 fL).

Question 22

What is a reticulocyte?

Answer 22

An immature red blood cell recently released from the bone marrow.

Question 23

How are reticulocytes identified on a blood film?

Answer 23

They appear larger and bluer than mature red cells (polychromasia).

Question 24

What does a high reticulocyte count indicate in anaemia?

Answer 24

Increased red blood cell production, often due to haemolysis or acute blood loss.

Question 25

What does a low reticulocyte count suggest in anaemia?

Answer 25

Impaired production of red blood cells in the bone marrow.

Question 26

What is the purpose of a blood film?

Answer 26

To assess red cell, white cell, and platelet morphology and detect abnormalities.

Question 27

Name an example of a red cell abnormality visible on a blood film.

Answer 27

Sickle cells in sickle cell anaemia.

Question 28

What white cell abnormality might be observed in a blood film during leukaemia?

Answer 28

Dysplastic neutrophils or blast cells

Question 29

When is a blood film particularly useful in haematological diagnosis?

Answer 29

When there is an abnormal full blood count or clinical suspicion of a blood disorder

Question 30

How does clinical information guide the interpretation of a blood film?

Answer 30

It helps correlate the findings with the patient’s symptoms and guide further investigations.