Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2.2 Haematology > Haematopoeisis > Flashcards

Haematopoeisis Flashcards

1
Q

What is haematopoiesis

A

The production of blood cells throughout life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How long do neutrophils last

A

1 day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How long do platelets last

A

7-10 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How long do rbcs live

A

120 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How long do lymphocytes and monocytes live

A

Months or years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

All blood cells arise from what type of cell

A

Haematopoietic Stem Cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a stem cell

A

A cell that has the ability to continuously divide and differentiate into various other kinds of cells/tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Who demonstrated the existence of stem cells

A

Dr James Till

Dr Ernest McCulloch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where do stem cells come from

A

In research they come from IVF embryos that have been donated

Stem cells are taken from these blastocysts

Inner cell mast of blastocyst is taken

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the sites of haematopoiesis

A

Bone marrow

Yolk sac

Liver

Spleen

Bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many days does it take for an egg to become a blastocyst

A

6 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

List the sites of haematopoiesis, from most cells produced to least from month one of development into adulthood

A

Yolk sac

Liver + spleen

Liver

Bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Comment on the bone marrow during childhood

A

Childhood marrow volume increases as child grows

Average 3 year old has 1500 ml active marrow

As child grows fat cells accumulate in marrow to form yellow marrow

Adults have approx 30% active (red) marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens to haematopoeisis if blood cell levels are low

A

Bone marrow can increase from 30% active to 100% active

Extramedullary haematopoeisis in liver and spleen may also re-occur (in disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does totipotent mean

A

Can develop into any cell type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does pluripotent mean

A

Can develop into some cell types

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

List some characteristics of stem cells
(6)

A

Unspecialised
Capable of dividing and renewing themselves for long periods of time
Can differentiate into specialised cell types
Many different functions
Function altered in disease states
Mature cells have short half life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How many Haematopoietic stem cells do we have

A

Limited number

1 per 20 million nucleated cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How many cells can a HSC make after 20 divisions

A

1 million cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What CD molecule do HSCs express

A

CD34

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the two pathways of haematopoiesis

A

Common myeloid pathway

Common lymphoid pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What two cells can the HSC differentiate into

A

Common lymphoid precursor

Common myeloid progenitor

23
Q

What cell types result from the myeloid pathway
(7)

A

Thrombocyte

Erythrocyte

Mast cell

Basophil

Neutrophil

Eosinophil

Macrophage

24
Q

What cell types result from the lymphoid pathway
(3)

A

Natural killer cell

T lymphocyte

B lymphocyte (-> plasma cell)

25
Q

What is the common myeloid progenitor often called

A

CFU-GEMM

26
Q

What does CFU-GEMM stand for

A

Colony forming unit

Granulocytes, erythrocytes, monocyte, megakaryocyte

27
Q

What is the common lymphoid precursor often called

A

CFU-L

Colony forming unit - Lymphocytes

28
Q

How does a stem cell know what it is going to become

A

It depends what acts on it e.g. hormones such as erythropoietin stimulating the formation of rbc

29
Q

What is SCF

A

Stem cell factor

30
Q

What does stem cell factor do

A

Stimulates the self renewal of pluripotent stem cells -> makes more

Acts on unipotent stem cells to make rbcs, platelets or wbcs

31
Q

What is needed for stimulation of erythropoiesis

A

Granulocyte-macrophage colony stimulating factor

EPO

32
Q

What is needed for stimulation of thrombopoiesis

A

Granulocyte-macrophage colony stimulating factor

Thrombopoietin

33
Q

What is needed for the stimulation of wbcs

A

Granulocyte-macrophage colony stimulating factor

Lymphocytes -> need no more stimulation

Monocytes need macrocytic colony stimulating factor

Granulocytes need granulocyte colony stimulating factor

34
Q

How can growth factors for certain cell types be important in donations

A

These factors can be given to mobilise certain cell types out into peripheral blood so they can be donated easily

35
Q

What stages of erythropoietin happen in blood

A

Last two stages -> in rare occasions steps before are seen especially in blood loss

36
Q

Why does high reticulocytes mean

A

Loosing blood somehow

37
Q

What does the presence of nucleated rbcs mean in peripheral blood

A

Bone marrow is under a lot of pressure to recover rbc count

38
Q

List the steps involved in erythropoiesis
(6)

A

Pronormoblast

Early normoblasts

Intermediate (polychromatic) normoblasts

Late (pyknotic) normoblasts

Reticulocytes

Red cells

39
Q

List the cells in simplified erythropoiesis
(5)

A

Megakaryocyte-erythrocyte progenitor

Pro-erythroblast

Erythroblast

Reticulocyte

Erythrocyte

40
Q

List the cells in thrombopoiesis

A

Megakaryocyte-Erythrocyte Progenitor

Megakaryocyte broken into platelets after TPO stimulation

41
Q

What happens when granulocyte-monocyte progenitor is stimulated by G-CSF

A

Neutrophil is formed

42
Q

What happens when granulocyte-monocyte progenitor is stimulated by stem cell factor

A

Basophil is formed -> can be converted to a mast cell in tissues

43
Q

What happens when granulocyte-monocyte progenitor is stimulated by IL-5

A

Eosinophil is formed

44
Q

What happens when granulocyte-monocyte progenitor is stimulated by M-CSF

A

Monocyte is formed

Converted into macrophage in tissues

45
Q

What does Growth factor (G-CSF) do

A

Matures cells e.g. neutrophils

Helps cells differentiate

Stops cell becoming other cell types

Suppresses apoptosis

Activates cells e.g. phagocytes

Helps cells proliferate

46
Q

List the cells in the development pathway of a granulocyte
(9)

A

HSC (Haemopoietic stem cells)

CFU-GEMM (common myeloid progenitor)

CFU- GM (granulocyte + monocyte precursor)

CFU-Neut

Myeloblast

Promyelocyte

Myelocyte

Metamyelocyte

Mature neutrophil

47
Q

What five stages come after GM-CFU in the development of a neutrophil

A

CFU-Neut

Myeloblast

Promyelocyte

Myelocyte

Metamyelocyte

Mature neutrophil

48
Q

What are we looking for in bone marrow samples

A

Myeloid : Erythroid ratio

Done by counting 200 to 300 cells

49
Q

Why do you need to know the age of the patient before assessing cellularity of bone marrow

A

Young child has 80% of the intertrabecular space occupied by haematopoietic cells

75 year old has only about 30%

50
Q

What does a really dark stain of bone marrow mean?

A

Leukaemia usually -> very little fat presence -> hypercellular

51
Q

What does a light stain of bone marrow mean

A

Aplastic anaemia -> hypocellular -> haematopoietic cells replaced by fat cells

52
Q

What stain do we use on bone marrow

A

Wrights Stain

53
Q

What stain do we use on bone marrow to test for iron

A

Perls Prussian Blue

54
Q

What happens to iron in bone marrow

A

10 to 20% of absorbed iron goes into a storage pool in cells of the mononuclear phagocyte system particularly fixed macrophages

Its also recycled into erythropoiesis so theres a balance of storage and use

2.2 Haematology (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions