Haematology

Question 1

What is the average lifespan of neutrophils?

Answer 1

2-4 days

Question 2

Where is bone marrow predominantly found in adults?

Answer 2

pelvis, sternum, skull, ribs and vertebrae

Question 3

In which places are we more likely to get cancer?

Answer 3

Places where the bone marrow is more active

Question 4

Approximately how much of bone marrow should be adipocytes?

Answer 4

50%

Question 5

Where do cells attach as they mature?

Answer 5

The stroma of the bone marrow

Question 6

What is haemopoiesis?

Answer 6

The formation of blood cellular components

Question 7

Which hormone drives RBC formation?

Answer 7

Erythropoietin

Question 8

Which hormone drives platelet production?

Answer 8

Thrombopoietin

Question 9

What is the origin of all blood cells?

Answer 9

Haemocytoblast (haematopoietic stem cell)

Question 10

What 2 types of progenitor cells are derived from the haemocytoblast?

Answer 10

myeloid progenitor and lymphoid progenitor

Question 11

Which cells are of the lymphoid lineage?

Answer 11

NK cells, B and T lymphocytes and plasma cells

Question 12

What are the functions of RBCs?

Answer 12

carry haemoglobin and deliver oxygen to tissues, maintain haemoglobin in reduced form, maintain osmotic equilibrium and generate energy

Question 13

Which state of haemoglobin is the binding state?

Answer 13

R state

Question 14

What are the roles of globin chains?

Answer 14

protect haem molecule, confer solubility and permit variation in oxygen affinity

Question 15

Where are the gene clusters for haemoglobin?

Answer 15

Chromosomes 11 and 16

Question 16

When do we switch from fetal to adult haemoglobin?

Answer 16

3-6 months

Question 17

What are the steps of erythropoiesis?

Answer 17

reduced partial pressure of oxygen detected in kidneys (hypoxia) : interstitial peritubular cells, increases production of erythropoietin, stimulates maturation and release of RBCs from bone marrow : acts on E-progenitor cells of bone marrow, haemoglobin conc rises, partial pressure of oxygen rises, erythropoietin production falls

Question 18

Which cells does erythropoietin act on?

Answer 18

E-progenitor cells in the bone marrow

Question 19

Which cells produce platelets?

Answer 19

Megakaryocytes

Question 20

Where are platelets stored until needed?

Answer 20

Spleen

Question 21

What are the functions of platelets?

Answer 21

1. adhere to connective tissue
2. aggregate with other platelets
3. form platelet plugs
4. facilitate clotting

Question 22

Name some structural features of platelets and why they are important

Answer 22

Phospholipid membrane = for clotting factor and platelet adhesion
Alpha granules = contain glycoproteins to make receptors
Dense bodies = contain molecules to aid platelet aggregation

Question 23

Which molecules aid platelet aggregation?

Answer 23

serotonin, ADP, catecholamines and calcium

Question 24

Which receptor can platelets adhere to?

Answer 24

vWF receptor

Von Willebrand factor

Question 25

What is the function of a fibrin mesh?

Answer 25

trapping platelets and RBCs

Question 26

What is the reticuloendothelial system?

Answer 26

cells identify and mount an appropriate immune response to foreign antigens and the recycling of nutrients and amino acids occurs

Question 27

What colour granules do eosinophils have?

Answer 27

Orange/red

Question 28

How long are eosinophils in circulation and what is their lifespan?

Answer 28

3-8 hours in circulation | 8-12 day lifespan

Question 29

What are the roles of eosinophils?

Answer 29

phagocytosis of antigen-antibody complexes and mediation of hypersensitivity reactions (asthma, skin inflammation)

Question 30

What is the half-life of basophils?

Answer 30

2.5 days

Question 31

What do the dense granules of basophils contain?

Answer 31

histamine, heparin, hyaluronic acid and serotonin

Question 32

Which cells form antibodies?

Answer 32

B lymphocytes

Question 33

What are the 2 types of T lymphocytes?

Answer 33

``` Helper cells (CD4+) Suppressor cells (CD8+) ```

Question 34

What can B cells transform into?

Answer 34

plasmablasts or memory cells

Question 35

What do plasmablasts do?

Answer 35

produce lots of antibodies and migrate to marrow to form plasma cells

Question 36

How do T cells differentiate?

Answer 36

migrate to thymus and undergo TCR rearrangement before differentiation

Question 37

What is the role of CD4+ cells?

Answer 37

induce proliferation and differentiation in T and B cells and activate macrophages

Question 38

What are CD8+ cells for?

Answer 38

Cytotoxic activity to induce apoptosis in other cells

Question 39

Which cells stop the formation of tumours?

Answer 39

NK cells

Question 40

How do NK cells kill?

Answer 40

By lysis (same mechanism as T cells)

Question 41

What is the average life span of a platelet?

Answer 41

10 days