Blood Flashcards
(118 cards)
1
Q
Name of the system that blood is part of
A
Haemopoietic system
2
Q
Temperature of blood at rest
A
About 38oC
3
Q
Reasons why blood temperature may exceed 40oC
A
Prolonged exercise
Fever
4
Q
Comparison of blood to water
A
5 times more viscous than water
5
Q
pH of blood at rest
A
Slightly alkaline
Around 7.4 (7.35 - 7.45)
6
Q
pH of blood during high intensity exercise
A
Lower than normal
Can be as low as 6.7
Acidic
7
Q
What percentage of body mass is blood volume
A
Around 7%
8
Q
Components to cardiovascular system and their general role
A
Heart
- The pump
Blood vessels
- The conductive system
Blood
- The fluid medium
9
Q
Functions of blood
A
Transport
Regulates body temperature
Buffers and balances acid base
Defends against pathogens and toxins
Restricts fluid loss at injury sites
Hydrolic functions….. (reproduction)
10
Q
Why does blood pH change during exercise
A
Acetic acid built up
This lowers the pH of the blood making it more acidic
11
Q
Blood distrubution rate at rest
A
5L/min
12
Q
Blood distrubution rate during exercise
A
20-40L/min
13
Q
Where is the majority of blood at any given time
A
In the veins
14
Q
Venipuncture
A
Phlebotomy
When whole blood is taken a superficial vein
15
Q
Reasons for using venipuncture to take blood
A
Superficial veins are easy to locate
They have thinner walls then arteries
Have lower blood pressure which allows quick wound sealing
16
Q
Other areas used to take blood
A
Tip of the finger
Ear
Toe
Heel
17
Q
Why are blood samples taken
A
Can check almost anything with a blood test
Blood goes everywhere and comes into contact with every part of the body
18
Q
Why do veins have thinner walls than arteries
A
Deal with less pressure
19
Q
Serum
A
Plasma without the clotting factors
20
Q
Amount of plasma in blood
A
46-63%
21
Q
Pecentage of formed elements in blood
A
37-54%
22
Q
Plasma
A
Transport medium
Carries plasma proteins and other things like glucose
Mainly H2O
23
Q
Percentage of plasma that is water
A
92%
24
Q
Formed elements in blood
A
Red blood cells
White blood cells
Platelets
White band when spun in a centrafuge between plasma and red part is white blood cells and platelets
25
Haematocrit definition
Medical term
Describes the percentage of cellular elements in the total blood volume
26
Normal haematocrit values
Men - 40-52%
Women - 36-48%
27
Polycythaemia
Excess red blood cell production
28
Used of measuring haematocrit values
Can give information for the diagnosis of polycythaemia
29
Other name for red blood cells
Erthrocytes
30
Red blood cells
Highly specialised
Contain haemoglobin
Lack most organelles
Incapable of self repair
31
Life span of red blood cell
120 days
32
How far does a red blood cell travel in it's lifetime
700 miles
33
Reason for lack of organelles in red blood cells
Mitochondria would steal oxygen that is being transported
Without other organelles their energy demands are low
34
Why can red blood cells not repair themselves or replicate themselves
Nuclei and other organelles required have been removed to make it more effecient
35
Where do red blood cells get their energy from
Anaerobic respiration
Uses glucose absorbed from surrounding plasma
36
Percentage of reb blood cells out of all cell in the body
Makes up 1/3 of all cells
37
Structure of red blood cells
Bi-concave disc
38
Benefits of red blood cell shape
**Large surface area to volume ratio** aids exchange
**Can stack up** and fall apart quickly - stacks more effeciently travel through blood vessels just larger than RBCs
**Can bend and flex** to squeeze trough capilaries narrower then the RBCs normal size
39
Haemoglobin
Intracellular protein in red blood cells
Each contains four haeme pigment complexes
Has a complex quaternary shape
40
How many molecules of oxygen does one red blood cell carry
About 1 billion
41
Haeme
Pigment complex on haemoglobin
Interacts with oxygen to form oxyhaemoglobin
Iron-oxygen interaction is very weak so can be seperated easily without damage
42
Ways oxygen is transported in blood (%)
Dissolved in blood (about 1.5%)
Attached to haemoglobin (about 98.5%)
43
Ways carbon dioxide is transported in blood (%)
Dissolved in blood (~7%)
As bicarbonate ions by reaction with water (~70%)
Attached to haemoglobin (~23%)
44
What is formed when CO2 attaches to haemoglobin
Carbaminohaemoglobin
45
Carboxyhaemoglobin
Formed when carbon monoxide binds to haemoglobin
46
What percentage of carboxyhaemoglobin is required to be fatal
Other effects
50%
Seizures and comas
47
Anemia
When blood doesn't have enough haemoglobin
Often treated by taking in more iron to make up for lack of haemoglobin
48
Fetal haemoglobin
Form of haemoglobin embryos/fetuses have
Binds more readily to oxygen than normal haemoglobin
Means the fetus can steal oxygen from the mother's blood at the placenta
49
Sickle cell anemia
Genetic disease
Red blood cells become sickle shaped
Can't carry as much oxygen
RBCs can't bend and fit through narrow spaces anymore
RBCs stick in capillaries and cause blocks
50
Process where RBCs are produced
Erythropoiesis
51
Erythropoiesis
Occurs only in red bone marrow
Produces red blood cells
52
Stages of erythropoiesis
1. Haemocytoblasts divide to produce myeloid stem cells
2. Myeloid stem cells differentiate into proerythroblast
3. Proerythroblasts proceed through erythroblast stages
4. Normoblast formed
5. Normoblast sheds necleus and becomes a reticulocyte
6. Reticuloctyre enters blood stream
7. After 24 hours in blood stream reticulocyte complete maturation and becomes a RBC
53
Erythropoietin
EPO
Glycoprotein
Appears in the plasma when peripheral tissue like the kidneys lack oxygen
54
Hypoxia
State of low tissue oxygen levels
55
When erythropoietin is released
During anaemia
Blood flow to kidneys declines
Oxygen content in the lungs declines
Respiratory surfaces of the lungs are damaged
56
Major effects of erythropoietin
Stimulates increased cell division rates in erythroblasts and in stem cells that produce erythroblasts
Speeds up maturation of RBCs by accelerating haemaglobin synthesis
57
What synthesises haemoglobin
Erythroblasts during erythropoiesis
58
# Image
Red blood cell turnover
59
Normal stages of red blood cell recycling
1. At the end of their life they are engulfed by phagocytes
2. Globular proteins broken down into component amino acids which are either released or metabolised
3. Heme units stripped of iron and converted to biliverdin
4. Biliverdin converted to bilirubin and released into blood stream
5. Bilirubin binds to album and taken to liver to be excreted in bile
6. In large intestine bilirubin broken down to urobilinogens and stercobilinogens
7. Urobilinogens excreted in urine
8. Stercobilinogens excreted in feces
60
Haemolysis
When red blood cells reputure before they can be broken down
Haemoglobin released into blood and breaks down instead of being recycled
61
Percentage of RBCs that haemolys each day
About 10%
62
Haemoglobinuria
When abnomarmally large numbers of RBCs haemolyse
Urine turns red or brown
63
Haematuria
Presence of intact red blood cells in urine
Happens when kidneys or vessels along the urinary tract are damaged
64
Biliverdin
What haeme units are converted to after their iron has been taken away
Organic compound with a green colour
65
Bilirubin
What biliverdin is converted into
Orange-yellow pigment
Binds to album and transported to liver
66
What is bilirubin broken down into
2 pigments
* Urobilinogens
* Stercobilinogens
67
Which product of bilirubin is excreted mainly in urine
Urobilininogens
68
When coming into contact with _____ the products of bilirubin break down into what
When they come into contact with oxygen:
Urobilinogens → Urobilins
Stercobilinogens → Stercobilins
69
What transports Fe2+ back to the bone marrow for RBC production
Transferrin in blood stream
70
Antigen
A substance that can trigger a protective defence response
71
What determines a persons blood type
The presence/absence of particular antigens on the surface of their RBCs
72
Antigens on human red blood cells
Genetically determined
Are glycoproteins or glycolypids
Almost 50 different antigens
73
3 important sufarce antigens on RBCs
A
B
Rh
74
Blood type A
* Surface antigen
* Antibodies
* Types that can recieve blood from
Has only type A antigens
Anti-B antigens
Can recieve from A and O
75
Blood type B
* Surface antigen
* Antibodies
* Types that can recieve blood from
Has only type B antigens
Anti-A antigens
Can recieve from B and O
76
Blood type AB
* Surface antigen
* Antibodies
* Types that can recieve blood from
Both A and B antigens
Has nither anti-A or anti-B
Can recieve from A, B, AB or O
77
Blood type O
* Surface antigen
* Antibodies
* Types that can recieve blood from
No surface antigens
Both anti-A and anti-B antigens
Can only recieve from O
78
Rh antigen
As well as A and B antigens
2 types
* Rh+
* Rh-
79
Other name for surface antigens on RBCs
Agglutinogens
80
Agglutination
When blood with antigens that don't match your own is given to you
Antibodies attacks the "foreign" red blood cells
Causes them to clump together and finally by hemolysed
81
Cross-match testing
Used to test if a donors blood is compatible with the recipitant
Anti-A, anti-B and anti-D antibodies are added to seperate samples of blood
Depending on which causes agglutination tells you which type it is
82
Universal donnor
Blood type O
Can be given to anyone
83
What's the best type of blood to give to someone who you don't know what their blood type is and why
O-
O- has no surface antigens so wont cause an immune respone
84
Leukocytes
White blood cells
85
Do white blood cells have a nuclues
What does this let them do
Yes
Control cell function and replication
86
Functions of white blood cells
Defend against pathogens
Remove toxins and waste
Attacks abnormal cells
87
White blood cell lifespan
From a few hours to decades
88
Where are white blood cells produced
In the bone marrow
89
5 classes of leukocytes percentages
**N**eutrophils (50-70%)
**L**ymphocytes (20-30%
**M**onocytes (2-8%)
**E**osinophils (2-4%)
**B**asophils (\<1%)
90
5 classes of leukocytes
**N**eutrophils
**L**ymphocytes
**M**onocytes
**E**osinophils
**B**asophils
91
Way to remember 5 classes of leukocytes
**N**ever **l**et **m**onkeys **e**at **b**ananas
92
Types of lymphoctyes
Active B-cells
T-cells
Natural killer cells
93
Where are white blood cells
Most time in connective tissue or in the organs of the lymphatic system
Only circulate for a brief period when injury/infection happens
94
How do white blood cells move
All types move by amoeboid movement
Cell pulls itself forward by rearranging bonds between actin filaments in the cytoskeleton
Requires ATP and calcium ions
95
Where can white blood cells go
Can go in blood stream
Hides out in connective tissue
Can also move through tissue by amoebic movement
96
How are white blood cells guided to pathogens?
Positive chemotaxis
97
Which white blood cells can perform phagocytosis
Neutrophils
Eosinophils
Monocytes
98
What white blood cells make up the bodies non-specific defences
Neutrophils
Eosinophils
Monocytes
Basophils
99
Which white blood cells make up the bodies specfic defences
Lymphocytes
100
T cells
Type of lymphocytes
Cell mediated immunity
Travel to target
From the thymus gland
Target of HIV for replication
101
B cells
Type of lymphocyte
Antibody-mediated immunity
Secretes antibodies
102
Natural killer cells
Type of lymphocytes
Performs immune surveilance
Lysises tumours, parasites or virally infected cells
103
Leukopenia
Abnormally low white blood cell count
104
Leukocytosis
Abnormally high white blood cell count
Normally due to an infection
105
Leukemia
Extremely high white blood cell count
106
Blood platelets
Produced in the bone marrow
No nucleus
Life of 9-12 days
Involved in blood clotting
1/3 in spleen as a potential reserve
107
Platelet role following an injury to a vascular wall
Release enzymes needed for clotting
Provide temporary patches in damaged vascular walls (platelet plug)
Shrink the break in the vessel wall by activating their actin and myosin filaments
108
Haemostasis
Clotting
4 stages
109
Stages of haemostasis
Vascular
Platelet
Coagulation
Clot retraction
110
Vascular phase of haemostasis
1. Blood vessel cut
2. Smooth muscle fibres contract (spasm) to slow blood loss
3. Basal lasminas exposed to blood
4. This triggers endothelial cells to release chemicals and hormones that help the repair process
5. Endothelial cells become sticky which may cause the sides of the cuts to stick together in small blood vessels
111
Platelet phase of haemostasis
1. Platelet plug forms within 15 seconds of injury by platelet aggregation
2. Platelets stick to the sticky endothelial surface release a variety of chemicals that promote aggregation, vascular spasm, clotting and vessel repair
3. Positive feeback loop produces a platelet plug that is reinforced as clotting occurs
112
Coagulation phase of haemostasis
Occurs 30 seconds after injury
Fibrin is manufactured
Fibrin strands form a framework that can trap red blood cells and platelets
113
How is fibrin produced in haemostasis
Specific clotting factors required from either
* Extrinsic pathway
* Intrinsic pathway
Activation of clotting factors activates Factor X
Factor X turns on a cascade of reactions that finally produces insoluable fibrin strands
114
# Haemostasis
Extrinsic pathway
Quick pathway
Clotting factors come from endothlial cells in the damaged vessel wall
115
# Haemostasis
Intrinsic pathway
Sustained pathway
Clotting factors come from circulating platelets in the blood
116
Clot retraction phase of haemostasis
Clot fully forms
Platelet plug contracts pulling torn edges of the blood vessel together
Prostacyclin limit the growth of the plug
Plasmin digests fibrin strands through fibrinolysis
117
Plasmin
Enzyme
Digests fibrin through fibrinolysis
Used in the clot retraction phase of haemostasis
118
Fibrinolysis
Process where fibrin is broken down
Uses the enzyme plasmin
Happens in the clot retraction phase of haemostasis
