Red Blood Cells Flashcards

1
Q

Where do all blood cells orginate?

A

Bone marrow

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

Which type of cells are the precursor of all blood cells?

A

Haemopoietic stem cells

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

Which 2 cell types do pluripotent haemopoietic stem cells give rise to?

A
  1. Lymphoid progenitor cells
  2. Myeloid progenitor cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What 3 types of cells do common lymphoid progenitor cells differentiate into?

A
  1. T cells
  2. B cells —> plasma
  3. NK cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What 4 types of cells do common myeloid progenitor cells differentiate into?

A
  1. Megakaryocytes —> platelets
  2. Erythrocytes
  3. Mast cells
  4. Myeloblasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What 4 types of cells do myeloblasts differentiate into?

A
  1. Basophils
  2. Neutrophils
  3. Eosinophils
  4. Monocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 types of granulocytes?

A
  1. Basophils
  2. Neutrophils
  3. Eosinophils
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 4 cell steps of platelet production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Megakaryocyte
  4. Platelets
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 cell steps of erythrocyte production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Erythrocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 3 cell steps of mast cell production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Mast cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 4 cell steps of basophil production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Myeloblast
  4. Basophil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 4 cell steps of neutrophil production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Myeloblast
  4. Neutrophil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 4 cell steps of eosinophil production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Myeloblast
  4. Eosinophil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 5 cell steps of macrophage production?

A
  1. Haemopoietic stem cell
  2. Common myleoid progenitor cell
  3. Myeloblast
  4. Monocyte
  5. Macrophage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 3 cell steps of natural killer (NK) cell production?

A
  1. Haemopoietic stem cell
  2. Common lymphoid progenitor cell
  3. NK cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 cell steps of B lymphocyte production?

A
  1. Haemopoietic stem cell
  2. Common lymphoid progenitor cell
  3. Small lymphocyte
  4. B cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the 4 cell steps of T lymphocyte production?

A
  1. Haemopoietic stem cell
  2. Common lymphoid progenitor cell
  3. Small lymphocyte
  4. T cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the lifespan of an erythrocyte?

A

120 days

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

What are the 2 essential characteristics of HSCs?

A
  1. Self-renew
  2. Differentiate to mature progeny
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 sites of haemopoiesis and when are they used?

A
  1. Yolk sac - 3 weeks gestation
    —> generate HSCs in mesoderm
  2. Liver - 6-8 weeks genstation
  3. Bone marrow - 10 weeks gestation
    - children —> all bones
    - adults —> pelvis
    —> vertebrae
    —> sternum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the difference between the location of haemopoesis in children vs adults?

A

Children —> all bones
Adults —> femur, vertebrae, sternum

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

What are pluripotent HSCs surrounded by in bone marrow? (3)

A
  1. Mesenchymal cells
  2. Endothelial cells
  3. Vasculature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What can disruption of HSC regulation cause?

A

Unbalanced proliferation and differentiation
1. Leukaemia
2. Bone marrow failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which 4 factors regulate haemopoiesis?

A
  1. Genes
  2. Transcription factors
  3. Growth factors
  4. Microenvironment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are haemopoietic growth factors?

A

Glycoprotein hormones
- Erythrocytes —> erythropoietin (EPO)
- Granulocytes and monocytes —> G-CSF
—> G-M CSF
—> cytokines
- Platelets —> thrombopoietin (TPO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Where are haemopoietic growth factors produced?

A

Bone marrow except EPO (kidney)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Where are B, T and NK cell progenitors found?

A
  1. B —> bone marrow
  2. T —> thymus
  3. NK —> bone marrow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What do mature B cells produce for immunity?

A

Antibodies —> humoral immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What do mature T and NK cells produce for immunity?

A

Cytokines —> cellular immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the 4 steps of erythrocyte differentiation?

A
  1. Proerythroblast
  2. Erythroblast
  3. Reticulocyte
  4. Erythrocyte
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which stain is used to see erythroblasts and why?

A

New methylene blue
- stains RNA —> can see maturing as nucleus lost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are reticulocytes and how are they identified on a blood film?

A

Immature erythrocyte
- circle with coloured dots —> RNA content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Which 4 nutrients/chemicals are a necessity for erythropoiesis?

A
  1. Iron
  2. Folic acid
  3. Vit B12
  4. EPO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are small erythrocytes described as? (diameter)

A

Microcytic
- <6μm
- iron deficieny anaemia
- anaemia of chronic disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are large erythrocytes described as?

A

Macrocytic
- >9μm
- megaloblastic anaemia

36
Q

What are 3 causes of iron deficiency?

A
  1. Blood loss
  2. Insufficient dietary intake
  3. Increased requirement
37
Q

Which disease leads to decreased iron availability?

A

Anaemia of chronic disease/inflammation

38
Q

Which 2 diseases can be identified by microcytic erythrocytes?

A
  1. Iron deficieny anaemia
  2. Anaemia of chronic disease
39
Q

What disease does iron/vit B12/folic acid deficiency lead to?

A

Megaloblastic anaemia

40
Q

Why does vit B12/folic acid deficiency create macrocytic erythrocytes?

A

Dec B12 and folate —> dec thymidine production —> dec DNA synthesis —> dec cell division (cells keep growing and don’t split)

41
Q

What is the cause of megaloblastic anaemia?

A

B12 or folic acid deficiency

42
Q

What stimulates erythropoietin production in the kidneys?

A

Hypoxia

43
Q

What are the 2 major functions of iron?

A
  1. Hb oxygen transport
  2. Mitochondrial proteins
    • cytochrome a, b, c —> ATP production
    • cytochrome P450 —> hydroxylation
44
Q

What are 3 symptoms of iron-deficiency anaemia?

A
  1. Koilonychia —> spoon shaped nails
  2. Glossitis —> inflammed tongue
  3. Angular stomatitis —> sores at mouth corners
    + hypochromic, macrocytic erythrocytes
45
Q

What is the cause of iron-deficiency anaemia?

A
46
Q

What is the average consumed vs absorbed mass of iron per day and why is there a difference?

A

10-20 mg/day —> 1-2 mg

47
Q

What foods are high in iron?

A

Haem - animal-products
Non-haem - soya beans

48
Q

What is haem iron?

A

Ferrous iron (Fe2+)

49
Q

What is non-haem iron and what must be done to absorb it?

A

Ferric iron (Fe3+)
- must be reduced (eg. by vit C) to be absorbed

50
Q

Why is consuming excess iron bad?

A

Toxic to heart and liver
- not excreted

51
Q

Where is iron stored in the body? (5)

A
  1. Bone marrow
  2. Red blood cells
  3. Spleen
  4. Muscle
  5. Liver —> ferritin
52
Q

How is iron lost during everyday life?

A

Skin shedding —> unregulated

53
Q

In what form is iron transported round the body?

A

Transferrin in plasma

54
Q

Which chemical inhibits iron absorption and storage?

A

Hepcidin

55
Q

When is hepcidin secreted and where from?

A

Secreted from liver when iron storage levels are high

56
Q

Where is iron absorbed from?

A

Duodenum

57
Q

Which 4 pro-inflammatory cytokines inhibit erythropoietin production?

A
  1. IL-1
  2. TNFα
  3. IL-6
  4. IFNγ
58
Q

Which 3 pro-inflammatory cytokines aid hepcidin production?

A
  1. IL-1
  2. TNFα
  3. IL-6
59
Q

What are the 2 major functions of vit B12?

A
  1. DNA synthesis
  2. Nervous system
60
Q

What are the 2 major functions of folic acid?

A
  1. DNA synthesis
  2. Homocysteine metabolism
61
Q

Why are vit B12 and folic acid essential for DNA synthesis?

A

Needed for dTTP synthesis —> needed for thymidine synthesis

62
Q

Why does a vit B12 or folic acid deficiency effect the bone marrow and how?

A

Effect all rapidly divinding cells (bone marrow, epithelial, gonads)
- megaloblastic erythropoiesis

63
Q

What are sources of vit B12?

A

Animal products
- fish, crab, chicken, eggs, milk etc.

64
Q

What are sources of folic acid?

A

Plant products
- citrus fruit, dark leafy greens, avocado, broccoli etc.

65
Q

When do folic acid requirements increase?

A
  1. Pregnancy
  2. Increased erythrocyte production (eg. haemolytic
    anaemias like sickle cell)
66
Q

What are the 2 steps of vit B12 absorption?

A
  1. Stomach —> combines with IF from gastric parietal
    cells
  2. Small intestine —> B12-IF binds to ileum receptors
67
Q

What are the 4 causes of vit B12 deficiency and why?

A
  1. Insufficient intake (eg. veganism)
  2. Pernicious anaemia —> autoimmune dec IF
  3. Malabsorption (eg. coeliac, surgery)
  4. Achlorhydria —> lack of stomach acid
68
Q

Where are erythrocytes destroyed?

A

Spleen —> by splenic macrophages after 120 days

69
Q

What happens to the haemoglobin of destroyed erythrocytes?

A

Haem —> bilirub - excreted in bile
—> iron back to bone marrow
Globin —> hydrolysed to amino acids

70
Q

What does erythrocyte survival depend on? (3)

A
  1. Membrane integrity
  2. Haemoglobin
  3. Cellular metabolism
    - issues —> haemolysis
71
Q

What causes pernicious anaemia?

A
72
Q

What is the shape of erythrocytes and why?

A

Biconcave discs
- no nucleus —> manoeuvre in small blood vessels
—> space for Hb to carry oxygen
- diameter: 7.5 µm
depth: 2 µm

73
Q

What does damage to vertical linkages in erythrocyte membranes cause them to become and why?

A

Spherocytes
- vertical linkages (ankyrin/spectrin) damaged —> lose
membrane —> too much cytoplasm —> swell —>
spherocytes —> haemolysis
- cause —> hereditary spherocytosis (auto dom)

74
Q

What does damage to horizontal linkages in erythrocyte membranes cause them to become?

A

Elliptocytes
- cause —> hereditary elliptocytosis
—> iron deficiency

75
Q

Why is the PPP important to erythrocytes?

A

Mode 3 of PPP —> NADPH produced —> reduces glutathione —> reduced glutathione = vital antioxidant in erythrocytes

76
Q

Why does G6PD deficiency affect erythrocytes?

A

Rate-limiting enzyme in PPP —> maintains NADPH reducing power
- G6PD deficiency —> less reduced glutathione —>
erythrocytes vulnerable to oxidant damage —>
severe intravascular haemolysis

77
Q

Which disease does the distribution of G6PD deficiency parallel and why?

A

Malaria
- hostile environment

78
Q

How can G6PD deficiency be identified on a blood film?

A
  1. Bite cells - oxidant damage to membrane and Hb
  2. Heinz bodies - Hb denatured
79
Q

What is polycythaemia?

A

Too many erythrocytes
- blood hyperviscosity —> vascular obstruction
—> thrombosis

80
Q

How is polycythaemia detected on a blood count?

A
  1. Hb inc
  2. RBC inc
  3. Hct inc
81
Q

What are the 2 types of polycythaemia?

A
  1. Pseudo - dec plasma volume —> high conc of
    erythrocytes
  2. Vera - actually inc in erythrocytes
82
Q

What causes pseudo-polycythaemia

A

Dec plasma volume

83
Q

What are the 4 causes of vera-polycythaemia?

A
  1. Blood doping/ overtransfusion
  2. Hypoxia - inc altitude
    - cardiac/respiratory disorders
    —> inc EPO
  3. Inappropriate EPO inc - renal tumour
    - administered (athletes)
  4. Myeloproliferation - bone marrow issue
84
Q

What is a visible symptom of hypoxia?

A

Central cyanosis —> blue tongue/lips

85
Q

How can polycythaemia be treated? (2)

A
  1. Venesection —> dec blood viscosity
  2. Drugs —> inhibit bone marrow erythropoiesis