Physiology of blood Flashcards
(218 cards)
1
Q
Name the components of blood
A
1, White blood cells
- Red blood cells
- Platlets
- Plasma
- Buffy coat
2
Q
What is the “Buffy coat” component of blood made up of?
A
Platlets and leukocytes
3
Q
What percentage of blood is made up of platelets and leukocytes ?
A
less than 1%
4
Q
What percentage of blood is made up of plasma?
A
55%
5
Q
What percentage of blood is made up of the formed elements? ?
A
45%
6
Q
What are the formed elements of blood?
A
- White blood cells
- Red blood cells
- Platelets
7
Q
When blood is centrifuged what happens?
A
It splits up into its different elements
1st layer: Plasma
2nd layer: Buffy coat
3Rd: Erythrocytes
8
Q
What is the function of blood?
A
- Delivers oxygen and removes carbon dioxide
- Maintains temperature, pH and fluid volume
- Provides protection from fluid loss
- Prevents infection
- Transports hormones and nutrients
- Transports waste products out of the body eg Urea
9
Q
What is plasma made up of/
A
90% water
8% solutes
10
Q
Name the solutes that make up plasma
A
Proteins like:
- Albumin (60%),
- Alpha and Beta globulins
- Gamma globulins,
- Fibrinogens
Gas
Electrolytes
11
Q
Name the main protein the makes up plasma
A
Albumin
12
Q
What is transported by the plasma?
A
- Organic nutrients eg carbohydrates, lipid, amino acids, vitamin
- Hormones
- Metabolic waste eg urea
13
Q
What is haematopoiesis?
A
It is the process that forms blood
14
Q
Which cells give rise to the formed elements of blood?
A
The haemocytoblasts (pluripotential hemopoietic stem cell (PHSC))
15
Q
What is another name for haemocytoblasts?
A
pluripotential hemopoietic stem cell (PHSC)
16
Q
How are haemocytoblasts transporter around the body?
A
They are pushed around by hormones and growth factors towards a certain pathway of differentiation depending on the body’s needs
17
Q
Are Hemocytoblasts seen in blood films and cytology? why?
A
No as they are easily broken
18
Q
Name the 2 different pathways Hemocytoblasts can take when differentiating
A
- The common myeloid progenitor
2. The common lymphoid progenitor
19
Q
What does the common myeloid progenitor pathway lead to?
A
The formation of:
- Megakaryocytes which form platelet
- Erythrocytes
- Mast cells
- Myeloblasts which form basophil, neutrophils, eosinophils and monocytes
20
Q
How are platelets formed from?
A
Megakaryocytes which is formed when Hemocytoblasts differentiate via the common myeloid progenitor pathway
21
Q
What does the common lymphoid progenitor pathway lead to?
A
- Natural killer cells
2. Small lymphocytes which form t lymphocytes and B lymphocytes
22
Q
What do red blood cells contain?
A
They contain haemoglobin
23
Q
Why is haemoglobin important?
A
As it helps transport respiratory gases
24
Q
How many red blood cells do we have?
A
Men have: 4.7-6.1 million per micro litre of blood
Females have: 4.2-5.4 million per micro litre of blood
25
How big are red blood cells?
Around 7.5 micrometers in diameter
26
What is special about the structure of red blood cells?
They lack mitochondria and don't have a nucleus
27
What shape are ed blood cells and why is this important?
They are biconcave
| This increases the surface area and increases flexibility
28
What is the benefit of red blood cells not having a mitochondria?
Give them more room to store ore haemoglobin
29
How are red blood cells produced?
Produced via haematopoiesis in bone
30
What is the lifespan of a red blood cell?
100-120 days
31
How are red blood cells destroyed?
Destroyed by macrophages in the spleen liver and bone §
32
Describe the structure of haemoglobin
It is made up of:
2 alpha chains
2 beta chains
1 iron containing haem group
33
What is erythropoiesis
How red blood cells form
34
What does erythropoiesis begin with?
Vitamin B12 and B9
35
Talk through the stages of erythropoiesis
1. Hemocytoblast are activated by vitamin B12 and B9 to differentiate into Late normoblast
2. Late normoblast leave the bone marrow
3. The nuclei is lost and destroyed by macrophages forming a reticulocyte
4. In 1-2 days the reticulocyte forms a erythrocyte (RBC)
5. Eventually erythrocytes are destroyed by macrophages forming erythropoietin
36
What happens as Hemocytoblast differentiate?
The cell size decreases during maturation as RNA and DNA decreases
The nucleus gradually shrinks
The colour of the cell changes from blue to red
37
What are reticulocyte ?
An immature red blood cell
38
What percentage of circulating cells are reticulocyte ?
1%
39
What are erythrocyte ?
They are red blood cells
40
What is erythropoietin?
A hormone produced by destroyed red blood cells
41
Why is erythropoietin important?
As It pushes the Hemocytoblast to differentiate into late normoblast
42
Give some differences between Hemocytoblast and late normoblast
1. Hemocytoblasts are bigger
2. Hemocytoblast have ore RNA and DNA
3. Hemocytoblast Has a bigger nucleus
4. Hemocytoblast are red late normoblasts are blue
43
Where is erythropoietin released from?
The kidneys
44
When is erythropoietin released?
Realeased from the kidneys in repose to hypoxia
45
Wha can hypoxia be caused by
1. Secondary to haemorrhage
2. Loss of red blood cells
3. Insufficient haemoglobin
4. Reduced oxygen
5. Increased damsons
46
What do erythropoietin stimulate?
Stimulates rapid maturation of committed red blood cells
47
What does the stimulation of erythropoietin lead to?
An increase in reticulocyte count circulating the body within 2 days
48
Why do men have more red blood cells than woman?
As testosterone enhances the production of erythropoietin leading to a higher RBC count in males
49
Talk through the stages of red cell death
1. Macrophages break down RBCs into haem and globin
2. Globing is broken down into amino acids and haem is broken down into down into Fe3+ (bound to transferrin) and biliverdin
3. Iron is transported to the liver
4. biliverdin is transported to the large intestine and ultimately exited out the body as faeces and urea
50
What do macrophages break RBCs into?
Haem and globin
51
Why is the iron broken down from haem bound to transferrin?
As iron is very reactive so when it binds to transferrin it not react with anything else
52
Talk through what happens to the iron element of haem when RBC death occurs?
Macrophages break down RBCs into haem
2. Haem is broken down into Fe3+ which Is bound to transferrin
3. This Fe3+ is transported to the liver and separated
4. Then is reforms and moves out of liver where it travels around the body
53
Talk through what happens to the biliverdin element of haem when RBC death occurs?
1. It is transported to the liver
2. Then it is transported to the large intestine where is is changed by bacteria to form bilirubin
3. bilirubin is then converted into urobilinogen and then Stercobilin
4. urobilinogen is then transported to the kidney as urobilin
5. urobilin leaves the kidneys as urea and Stercobilin leaves the body as faeces
54
What is anaemia?
It is a condition where a person has a decrease int eh number of red blood cells OR they have less than the normal quantity of haemoglobin in their blood
55
What anaemia due to?
1. Excess blood loss
2. Excess red blood cell destruction
3. Deficient red blood cell production
56
What are the most common causes of iron deficient anaemia?
1. Parasitosis
2. Dietary deficiency
3. Blood loss
4. Malabsorption
5. Pregnancy
57
Give some symptoms of iron deficient anaemia
1. Tiredness
2. Pale
3. Light headedness
4. Irritable
5. Poor wound healing
6. Beefy red tongue (glossitis)
7. Burning mouth syndrome
8. RAS
9. Candidal infections
58
Name the different types of anaemia
1. iron deficient anaemia
| 2. Pernicious Anaemia
59
What is Pernicious Anaemia?
It is vitamin B12 deficient anaemia
60
What is Pernicious Anaemia?
A lack of red blood cells due to a deficiency in vitamin B12
61
What can Pernicious Anaemia be due to?
Due to lack of intrinsic factors allowing absorption of vitamin B12
62
What can Pernicious Anaemia caused by?
1. Autoimmune condition
2. Tapeworms
3. Poor diet
4. Celiac
5. Weight loss
6. Neurological symptoms
7. glossitis,
8. angular cheilitis
63
How Is Pernicious Anaemia treated?
Treated with oral supplements and intramuscular B12 injections
64
What are Haemoglobinopathies
Conditions where there is something wrong with haemoglobin
65
Give examples of Haemoglobinopathies
1. Sickle cell
| 2. Thalassaemia
66
What does sickle cell and Thalassaemia cause?
Leads to the production of abnormal RBSc that are broken down more quickly by the body
67
What can happen if you destroy more RBCs than you make?
You can get haemolytic anaemia
68
Is Sickle Cell Anaemia recessive or dominant?
Autosomal Recessive
69
What cases Sickle Cell Anaemia
Caused by a genetic mutation on chromosome 11 where the Glut protein is converted into Val at position 6
This produces a sickle component instead of a beta chain changing the shape of the RBC
70
How is sickle cel anaemia treated?
Treated with hydroxyurea to increase HbF production and prevent abnormal sickle cells being made
71
What does it mean if you are a Heterozygote for sickle cell anaemia
Means you have some sickle shaped RBC and some normal RBC
| This is beneficial as it provides protection from malaria
72
Name the 2 different types of Thalassaemia
Alpha Thalassaemia
| Beta Thalassaemia
73
What is alpha Thalassaemia
A reduction in alpha unit production
| This leads to an excess of beta units
74
What is beta Thalassaemia?
A reduction in beta unit production
| This leads to an excess of alpha units
75
Which type of Thalassaemia is more common?
Beta Thalassaemia
76
How many genes make up the alpha unit of RBCs?
2 genes so 4 alleles
77
How many genes make up the beta unit of RBCs?
1 gene so 2 alleles
78
If you lose one alpha unit allele what happens?
No problem
79
If you lose 2 alpha unit allele what happens?
May suffer from mild anaemia/microcytosis
80
If you lose 3 alpha unit allele what happens?
May suffer from severe anaemia
81
If you lose 4 alpha unit allele what happens?
Incompatible with life
82
What is microcytosis?
A condition where you have smaller red blood cells
83
Name the 5 different types of leukocytes from greater amount to least amount found in the blood
1. Neutrophils (65%)
2. Lymphocytes (25%)
3. Monocytes (6%)
4. Eosinophils (3%
5. )Basophils (1%)
84
How big are leukocytes?
400-11000 cells mm^3
85
What happens when you have increased number of white blood cells
leukocytosis
86
When might someone have leukocytosis?
Seen in:
1. Infections
2. Neoplasia
3. Autoimmune diseases
4. Strenuous exercise
5. Stress
6. Allergies
87
What happens when you have a decreased number of white blood cells
You can get leukopenia
88
When might someone have leukopenia?
Seen in:
1. Chemo therapy
2. Radio therapy
3. HIV/AIDS
4. Some infections
5. Mineral deficiency
89
How big are neutrophils?
10-12 micrometres in diametre
90
Name the main targets of neutrophils
Bacteria and fungi
91
What type of nucleus do neutrophils have?
Multi lobes
92
What type of granules do neutrophils have?
Fine granules that are faintly pink
93
What is the life span of a neutrophil?
6hours - a few days
94
How big are lymphocytes ?
7-8 micrometres (small)
| 12-15 micrometres (Large)
95
Name the main targets of lymphocytes
```
T cells
B cells
NK cells
Bacteria
Viruses
Tumour cells
```
96
What type of nucleus do lymphocytes have?
Deeply stained eccentric
97
What type of granules do lymphocytes have?
They have NK cells and cytotoxic T cells
98
What is the lifespan of a lymphocytes ?
Years for memory cells
| Weeks for all other types
99
How big are monocytes?
15-30 micrometers
100
What is the function of monocytes
To migrate to become redden macrophages
101
Describe the nucleus of a monocyte
It is kidney shaped
102
Do monocytes have granules?
no
103
What is the lifespan of a monocyte?
Hours-days
104
How big are Eosinophils
10-12 micrometres in diamtre
105
What is the function of Eosinophils
To indice teh allergic inflammatory response and attack parasites
106
Describe the nucleus of Eosinophils
It is bilobed
107
Describe the granules found in Eosinophils
They are fill of pink and orange
108
What is gteh life span of Eosinophils
8-12 days
109
What percentage of leukocytes are made up of Neutrophils
65%
110
What percentage of leukocytes are made up of Lymphocytes
25%
111
What percentage of leukocytes are made up of monocytes
6%
112
What percentage of leukocytes are made up of eosinophils
3%
113
What percentage of leukocytes are made up of basophils
1%
114
What is leukocytosis?
An increased number of white blood cells
115
What is leukopenia
A decreased number of white blood cells
116
How big are Basophils
12-15micrometres
117
What is the function of Basophils
To please histamines for inflammatory response
118
Describe the nucleus of Basophils
BI or Tri lobed
119
Describe the granules found in Basophils
They are large an blue
120
What is the life span of Basophils
Few hours- few days
121
What is diapedesis?
It is how white blood cells leave the blood stream
122
Name the steps involved in the leaving of a white blood cell from the blood steam
1. Chemoattraction
2. Rolling adhesion
3. Tight adhesion
4. Transmigration
123
Talk through how a white blood cell leaves the blood stream
1. It is chemo attracted to an area where it is needed
2. They then get a rolling adhesion from the blood Flow where they stick on the side of the walls and roll
3 .They then stop this is called tight adhesion
4. They then slip between the endothelial cells this is called transmigration
124
Where are monocytes found?
They are found in the bone marrow and blood
125
Where are kupffer cells found?
Liver
126
Where are histiocytes found?
Tissues
127
Where are microglia found?
Central nervous system
128
Where are hofbauer cells found
Placenta
129
Where are intraglomerular mesangial cells found
Kidneys
130
Where are osteoclasts found
Bone
131
What are platelets?
Small fragments of megakaryocytic
132
How is the formation of platelets regulated?
Regulated by thrombopoietin
133
Describe how platelets look under a microscope
Theres a blue staining outer region filled with purple granules
134
What do the granules in platelets contain?
1. Serotonin
2. Ca2+
3. Enzymes
4. ADP
5. Platelet derived growth factor (PDGF)
135
How big are platelets?
2-3 micrometres
136
What shape are platelets cells?
Biconcave in shape
137
What is the ratio of platelets to RBC?
1:10 TO 1:20
138
How many platelets are found in the blood?
Around 250,000-500,000 cells/mm3
139
What process occurs when you cut yourself?
Haemostasis
140
Name the 4 steps of Haemostasis
1. Vessel injury
2. Vascular spasm
3. Platlets plug formation
4. Coagulation
141
Talk through thstages of Haemostasis
1. Vessel is damaged
2. The damaged vessel constricts reducing blood flow in reposes to endothelial cell injury, smooth muscle injury, pain and platelets
3. Platlets adere to damaged endothelium and then degranulate
4. Platlets adhere to the collagen fibres in the wound becoming spiky and causing more platelets to stick to the plug and cause further vasoconstriction creating a feedback loop
5. Clotting factors become activated and begin deposition of fibrin creating meshwork
6. Coagulation reinforces the clot
142
How is plug activation regulated?
Regulated by Von Willebrand factor which is found in plasma
143
What is the clot formed by when you cut yourself
It is formed by the transformation of soluble fibrinogens to insoluble fibrin
RBCs and platelets stay trapped in the mesh
144
What does blood clotting involve?
2 different pathways made up of a cascade of circulating proteins
145
Name the two pathways that make up Haemostasis
1. Intrinsic pathway
| 2. Extrinsic pathway
146
What is the intrinsic pathway of Haemostasis activated by?
Activated by trauma inside the vascular system
147
Give examples of stimuli that may activate the intrinsic pathway of Haemostasis
1. Exposed endothelium
2. Chemicals
3. Collagen
4. Negatively charged surfaces
148
Which factors are involved in intrinsic Haemostasis
Factors VII, XI, IX an VIII
149
What is the extrinsic pathway of Haemostasis activated by?
Activated by external trauma when blood leaves the vascular system
150
Which factors are involved in extrinsic Haemostasis?
Factor VII
151
Which of the 2 pathways of Haemostasis is faster?
Extrinsic Haemostasis is fast
152
What is the purpose of the intrinsic and extrinsic pathways of Haemostasis
To turn soluble fibrinogen into insoluble fibrin creating a stable clot
153
Give some disorders of Haemostasis
1. Bleeding disorders
| 2. Thromboembolic disorders
154
Name some bleeding disorders
1. Thrombocytopenia
2. Clotting Factor Deficiencies
3. Impaired Liver Function
4. Von Willebrand Disease
155
What is Thrombocytopenia?
It is when a person has too few platelets
156
What can Thrombocytopenia cause?
Spontaneous bleeding
157
Why might a person with Thrombocytopenia suffer from spontaneous bleeding?
Due to suppression or destruction of bone marrow
158
How do we diagnose Thrombocytopenia?
By checking a patients platelet count
| If it is below 50,000/mm3 then the person may have Thrombocytopenia
159
How is Thrombocytopenia treated?
Treated with transfusion of concentrated platelets
160
How does Thrombocytopenia arise?
It can be idiopathic (spontaneous)
161
What happens if someone liver function is impaired?
Their ability to produce procoagulant is impaired
162
Given an example of procoagulants
Vitamin k
163
What can cause liver function impairment?
Vitamin K deficiency
Hepatitis
Cirrhosis
Injury
164
What forms is vitamin K found in?
2 forms:
| K1 and K2
165
Why is vitamin k important?
1. It allows for the synthesis of coagulation factors
2. Allows binding of calcium to activate some of the coagulation factors
3. It carboxylises glutamate redoes in protein which are needed for binding proteins to activate
166
Why is the carboxylation of glutamate important?
As it is needed for binding proteins to activate
167
What carboxylates glutamate residues found in proteins?
Vitamin k
168
Where is K1 found?
Found in leafy veg
169
How do we get K2?
It is synthesised by flours in animal and human gut flors
170
What is vitamin k used to reverse?
Warfarin overdoe
171
Where is vitamin K stored?
stored in fatty tissues of the body
172
Name the most common hereditary coagulation disease
Von Willebrand Disease
173
State the different types of Von Willebrand Disease
Type 1: Autosomal dominant (Least severe)
Type 2: Autosomal dominant
Type 3: autosomal recessive (most severe)
4. Platelet type (autosomal dominant)
174
Which of the 4 different types of Von Willebrand Disease is the most severe?
Type 3 the autosomal recessive type
175
What is Von Willebrand Disease
A deficiency of Von Willebrand factor found in salsa and subendothelial connective tissue
176
What is Von Willibrands factor?
It is essentially a binding molecule to make other molecules more stab
177
What can Von Willibrands factor bind to?
Binds to Factor viii in circulation increasing its half life from 1-2 hour to 12 hours
178
What does Von Willibrands factor do when it is released from damaged endothelial cells?
It allows links between platelets and vessel wall collagen
179
What do Haemophilias include?
They include several similar heritor bleeding disorders
180
Gives some symptoms ofHaemophilias
prolonged bleeding, especially into joint cavities
181
How are Haemophilias treated?
Treated with plasma transfusion s and injection of missing factors
182
Name the two main types of Haemophilias
Type a
| Type b
183
Which factor is deficient in type A Haemophilia?
Factor VIII
184
How is Haemophilia A passed on?
It is X linked recessive
185
How many males suffer from Haemophilia A
1 in every 5000
186
What is another name for Haemophilia B
Christmas disease
187
Which factor is deficient in Haemophilia b?
Factor IX
188
How is Haemophilia B passed on?
It is X linked recessive
189
How many males suffer from Haemophilia B
1 in every 30,000
190
What is blood type cased on?
The precedence of 2 major antigens in Red blood cell membranes A and B
191
What is an antigen ?
A protein on the surface of a cell membrane
192
What are antibodies
Proteins made by lymphocytes in plasma which are made in repose to the precise of foreign antibodies
193
Name the 4 different blood types
A, B , AB, O
194
Which antigen is present in people with blood type A?
Antigen A
195
Which antigen is present in people with blood type B?
Antigen B
196
Which antigen is present in people with blood type AB?
Antigen A and B
197
Which antigen is present in people with blood type o?
Neither A or B antigen (Universal donors)
198
Which antibody is present in people with blood type A?
Anti A
199
Which antigen is present in people with blood type B?
Anti B
200
Which antigen is present in people with blood type AB?
No antibody (Universal receivers)
201
Which antigen is present in people with blood type O?
Anti A and Anti B
202
Give the genotype of a person with blood type A
IA, IA
OR
IA, IO
203
Give the genotype of a person with blood type B
IB, IB
OR
IB, IO
204
Give the genotype of a person with blood type AB
IA, IB
205
Give the genotype of a person with blood type O
IO, IO
206
Which of the 4 phenotypes for blood group is recessive?
O
207
Which of the 4 phenotypes for blood group is dominant?
None of them both A and B share co dominants
208
What does the Rh factor describe?
Describe the present of Rhesus antigen D
209
Which is domient:
| Rh+, Rh-?
Rh+
210
What problems can arise if a mother is Rh- and her foetus is Rh+
Can lead to anti-rhesus antibodies from mother attacking the foetal blood cells, causing haemolytic anaemia
211
Which of the different blood groups is the most common?
O positive 37.4%
212
What is the frequency of blood type O negative
6.6%
213
What is the frequency of blood type A positive
35.7%
214
What is the frequency of blood type A negative
6.3%
215
What is the frequency of blood type B positive
8.5%
216
What is the frequency of blood type B negative
1.5%
217
What is the frequency of blood type AB positive
3.4%
218
What is the frequency of blood type AB negative
0.6%
