Haemopoiesis

Question 1

what is haemopoiesis

Answer 1

formation of blood cells

Question 2

types of white cells

Answer 2

granulocytes
macrophages
lymphocytes

Question 3

types of granulocytes and their functions

Answer 3

neutrophils: phagocytosis
eosinophils: destroy parasites, modulate hypersensitivity reactions
basophils: modulate hypersensitivity reactions

Question 4

precursor for macrophage

Answer 4

monocytes

Question 5

types of lymphocytes

Answer 5

B cells: antibodies
T cells: cell mediated immunity
Natural killer cells: anti-viral/tumour

Question 6

life span of:
RBCs
Neutrophils
Platelets

Answer 6

RBCs = 120 days
Neutrophils = 7-8 hours
Platelets = 7-10 days

Question 7

precursor for platelets

Answer 7

megakaryocytes

Question 8

progression from premature cell to mature neutrophil

Answer 8

pre-myeloblast – myeloblast – premyelocyte – myelocyte – metamyelocyte – neutrophil

Question 9

what is meant by the term ‘blast’

Answer 9

primitive nucleated precursor cell

Question 10

what are haemopoietic stem cells derived from

Answer 10

mesoderm

Question 11

where is the first site of erythroid activity in an embryo

Answer 11

yolk sac (stops by week 10)

Question 12

where are the other sites of erythroid activity in an embryo and their time frames

Answer 12

liver (starts by week 6)
spleen (starts by week 12)
bone marrow (starts by week 16)

Question 13

main sites of haemopoiesis in an adult

Answer 13

bone marrow of skull, ribs, sternum, vertebra,pelvis

Question 14

what are the names of the cells that:
form bone
break down bone

Answer 14

bone forming = osteoblasts

bone break down = osteoclasts

Question 15

where is a bone marrow biopsy often taken

Answer 15

posterior iliac crest

Question 16

how does blood enter the bone

Answer 16

arteries feed into sinusoids

Question 17

what are sinusoids

Answer 17

flattened capillaries with gaps between epithelial cells- regulate which cells pass in and out of blood vessels

Question 18

importance of sinusoids

Answer 18

allow formed blood cells to pass through gaps in endothelial cells to enter circulation

Question 19

link between RBCs and sinusoids

Answer 19

release of red cells is associated with sinusoidal dilatation and increased blood flow

Question 20

link between megakaryocytes and sinusoids

Answer 20

extend long branching processes called pro platelets into the sinusoidal blood vessels - blood sheers off platelets and they enter the blood stream

Question 21

what is red marrow and what is yellow marrow

Answer 21

red = haemopoietically active
yellow = fatty inactive

Question 22

how does the composition of marrow change with age

Answer 22

increase in yellow marrow

Question 23

what is the myeloid: erythroid ratio

Answer 23

relationship of neutrophils and precursors to proportion of nucleated red cell precursors

Question 24

what is neutrophil maturation regulated by

Answer 24

G-CSF (granulocyte-colony stimulating factor)

Question 25

what regulates growth and development of megakaryocytes

Answer 25

thrombopoietin

Question 26

what is important for cytokine growth

Answer 26

stem cell factor

Question 27

what is important for stem cell development

Answer 27

CXCL12

Question 28

What is immunophenotyping

Answer 28

study of antigen expression using specific antibodies

Question 29

what is it called when there is too many blood cells

Answer 29

myeloproliferative disorders