Blood Constituents and Haemopoiesis

Question 1

What is the production of blood cells termed?

Answer 1

Haemopoiesis

Question 2

What are blood cells derived from?

Answer 2

Pluripotent stem cells, capable of making all the different types of blood cells

Question 3

What are the sites of haematopoiesis in the embryo?

Answer 3

Yolk sac then liver

3rd to 7th month- spleen

Question 4

What are the sites of haematopoiesis at birth?

Answer 4

Mostly bone marrow, liver and spleen when needed

Question 5

What are the sites of haematopoiesis from birth to maturity?

Answer 5

Number of active sites in bone marrow decreased but retain ability to haematopoiesis

Question 6

What are the sites of haematopoiesis in adults?

Answer 6

Bone marrow of skull, ribs, sternum, pelvis and proximal ends of femur

Question 7

How many red cells are made per minute?

Answer 7

100 million

Question 8

How many neutrophils are made per minute?

Answer 8

60 million

Question 9

How many platelets are made per minute?

Answer 9

150 million

Question 10

What has to happen to a stem cell to make blood?

Answer 10

Proliferation
Differentiation (cell development)
Most stem cells sit in a quiescent state

Question 11

What is the progression of maturation to mature neutrophils seen in the marrow?

Answer 11

Myeloblast to promyelocyte to myelocyte through metamyelocyte forms eventually to band forms and neutrophils that are seen in the blood

Question 12

What is the progression of maturation to mature red cell (erythropoiesis)?

Answer 12

Pronormoblast
Basophilic/early normoblast
Polychromatophilic/intermediate normoblast
Orthochromatic/late normoblast
Reticulocyte
Mature red cell/erythrocyte

Question 13

What are the granulocytes?

Answer 13

Eosinophils
Basophils
Neutrophils

Question 14

What is the structure of neutrophils?

Answer 14

Segmented nucleus (polymorph)
Neutral staining granules

Question 15

What is the function of neutrophils?

Answer 15

Short life in circulation- transit to tissues
Phagocytose invaders
Kill with granule contents and die in the process
Attract other cells

Question 16

What increases the number of neutrophils?

Answer 16

Body stress- infection, trauma, infarction

Question 17

What is the structure of eosinophils?

Answer 17

Usually bi-lobed

Bright orange/red granules

Question 18

What is the function of eosinophils?

Answer 18

Fight parasitic infections

Involved in hypersensitivity

Question 19

What can elevate the numbers of eosinophils?

Answer 19

Patients with allergic conditions (e.g. asthma, atopic rhinitis)

Question 20

What is the structure of basophils?

Answer 20

Infrequent in circulation

Large deep purple granules obscuring nucleus

Question 21

What is the function of basophils?

Answer 21

Circulating version of tissue mast cell
Mediates hypersensitivity reactions
FcReceptors bind IgE
Granules contain histamine

Question 22

What is the structure of monocytes?

Answer 22

Large single nucleus

Faintly staining granules, often vacuolated

Question 23

What is the function of monocytes?

Answer 23

Circulate for a week and enter tissues to become macrophages
Phagocytose invaders- kill them, present Ag to lymphocytes
Attract other cells
More long lived than neutrophils

Question 24

What is the structure of lymphocytes?

Answer 24

Mature – small with condensed nucleus and rim of cytoplasm
Activated (often called atypical) – large with plentiful blue cytoplasm extending round neighbouring red cells on the film, nucleus more ‘open’ structure

Question 25

What is the function of lymphocytes?

Answer 25

Numerous types and function (B, T, NK)
Cognate response to infection
Brains of immune system

Question 26

What will immunophenotyping show?

Answer 26

Expression profile of proteins (antigens) on the surface of cells

Question 27

What will bio-assays show?

Answer 27

Culture in vitro and show lineage of progeny in different growth conditions

Question 28

What are the posterior iliac crests common sites for?

Answer 28

Bone marrow aspiration and biopsy