Blood, it's components and groups Flashcards
List the 3 functions of blood
Transportation
Protection
Regulation
What gases does blood transport?
Oxygen
Carbon dioxide
What substances other than gases does blood transport?
H2O, nutrients, waste products and hormones
How is blood involved in temperature regulation?
It transports heat - vaso constriction and vaso dilation
How does blood fulfil a protective function?
Clotting/Coagulation
Immunity/Defense
Inflammation (WBC)
What does blood help to regulate?
Fluid
pH
Temperature
Hormones
What type of tissue is blood?
Liquid connective tissue
What makes blood a connective tissue?
Cells are contained in a liquid plasma matrix
What is the composition of blood in percentages?
Plasma 55%
Cells 45%
What is the process that seperates cells from plasma?
Centrifuging
What is haematocrit?
The cells separated from plasma by the centrifuge
What does PCV stand for?
Percentage Cellular Volume
What is a normal PCV in males?
40-54%
What is a normal PCV in females?
37-47%
What are the components of plasma?
Water Protein Electrolytes Glucose/hormones Organic waste products
What percentage of Plasma is water?
90%
What percentage of Plasma is protein?
8%
What percentage of Plasma is electrolytes?
0.9%
What are the plasma proteins?
Albumins
Globulins
Fibrinogen
What are the organic waste products found in Plasma?
Urea
Creatinine
Uric Acid
What is the width of a mature RBC?
7microns
What is the lifespan of an RBC?
120 days
What is the shape of an RBC?
Bi-Concave discs
What is the function of an RBC?
Transport Gas
What gases are transported by RBC?
Oxygen
Carbon Dioxide
What do RBC’s contain?
Haemoglobin
Carbonic Anhydrase Enzyme
Why do RBC’s have a special shape?
Increased flexibility
Increased surface area
Why do RBC’s contain Carbonic Anhydrase enzyme
To produce Carbonic Acid from CO2 and Water
On average how many haemoglobin molecules does an RBC contain?
Over 1 million
How many protein chains does a Haemoglobin molecule contain?
4 chains
What is the protein part of Haemoglobin?
Globin
How many Oxygen atoms does Haemoglobin carry?
4
What metal does Haemoglobin contain that blinds with oxygen molecule?
Iron (Fe+2)
How does Foetal haemoglobin differ to adult haemoglobin?
In it’s affinity to O2, which is greater in foetal haemoglobin.
Why is RBC count lower in women?
Androgens (male hormones) stimulate RBC production
Menstrual losses
List the two categories of Leukocytes
Granulocytes
AGranulocytes
List the three types of Granulocytes
Neutrophils 60-70%
Eosinophils 2-4%
Basophils <1%
List the two types of AGranulocytes
Lymphocytes 25-33%
Monocytes 3-8%
What is the function of a Neutrophil?
Phagocyte in bacterial infections
When are eosinophil counts high?
Parasitic infections
Allergies
When are basophil counts high?
Chicken Pox
Sinusitis
Diabetes
When are lymphocyte counts high?
During infection and immune responses
What is the function of lymphocytes?
Destroy foreign cells & virally infected cells
What triggers a macrophagic response in Monocytes?
Cytokines
Where are monocytes active when under the influence of cytokines?
Spleen
Kidney - mesangial cells
Liver - Kupfer cells
Brain - microglia
In an embryo where are blood cells manufactured?
Yolk Sac
In an unborn baby where are blood cells manufactured?
Liver, spleen
Following birth, where are blood cells manufactured?
Red Bone Marrow (RBC, WBC, Platelets) Lymphoid Tissues (WBC production/maturation)
What is Haemopoiesis?
Manufacture of Blood cells
What is EPO?
Ertythropoietin
Where is EPO secreted?
Kidney and Liver
What is EPO?
Hormone that controls manufacture of Red Blood Cells
What triggers release of EPO?
Hypoxia
What type of cell gives rise to all cell types?
Stem Cells
What are the names of the transitional cells that eventually develop into an Erythrocyte?
Pro-erythroblast (committed cell)
Erythroblast
Normoblast
Reticulocyte
At what rate are RBC’s manufactured on average?
2.5 million per second
Over what period do RBC’s develop?
3-5 days
What happens to a committed and precursor cell as it matures into an RBC?
Reduction in cell size
Synthesis of Haemoglobin
Loss of nucleus
What percentage of circulating RBC’s are reticulocytes?
0.5 - 1.5%
Where in the body do RBC’s expire?
Spleen - cells burst in narrow channels
What function do the macrophages in the liver and spleen perform in relation to RBC expiration?
They digest the RBC components
Convert Haem to bilirubin
How is Haem dealt with when an RBC expires?
Broken down to Iron which is stored by the body
Haem in turn broken down into Biliverdin, then bilirubin.
What happens to Bilirubin?
This forms part of bile and is then expelled by the body in faecal matter, giving faeces it’s brown colour
What are some typical causes of Hypoxia?
Lung disease Smoking High Altitude Increase in exercise Bleeding
What is hypoxaemia?
An abnormally low amount of oxygen in the blood
Which organs in the body register hypoxaemia and in turn release EPO?
Liver and kidneys
What action does EPO have on red bone marrows?
Stimulates them to produce more Red blood cells
What does the body need for RBC production?
Iron
B12
Folic Acid
What are common food sources of iron?
Red Meat Shellfish Dried Fruit Nuts Legumes
How is iron lost from the body?
Urine
Faeces
Bleeding
Where is iron stored in the body?
Liver
Where in the body is iron utilised?
Bone Marrow (Haemoglobin) Muscle (myoglobin) All cells (enzymes in mitochondria)
What are the causes of anaemia?
Decrease RBC production or Haemoglobin synthesis Inadequate nutrition Loss of blood RBC destruction (haemolytic anaemias) Cell abnormalities (Sickle Cell disease)
List the types of Anaemia
Diet Induced Macrocytic/Microcytic Pernicious - Macrocytic Haemorrhagic - normocytic Haemolytic Aplastic
What is a platelet?
Small fragment of megakaryocyte cytoplasm
How do platelets move?
Amoeboid movement
What size are platelets?
2-4 microns
What are the functions of platelets?
Secrete Chemicals
Form temporary platelet plugs
Dissolve old blood clots
Attract leukocytes to sites of inflammation
What chemicals do Platelets secrete?
Clotting factors
Factors for endothelial repair
vasoconstrictors in broken vessels
What is primary haemostasis
Temporary Platelet plug
What is secondary haemostasis
Co-agulation, stable clot
What is vascular spasm?
Constriction of a broken blood vessel
What triggers vascular spasm?
Pain receptors
What causes the blood vessel to constrict?
The release of serotonin by platelets
Thrombin is a clotting factor found in Plasma? True or False
True
Which organ manufactures pro-thrombin?
Liver
What action does Thrombin have on Fibrinogen?
Turns it from soluble to insoluble fibrin
What are the two coagulation pathways?
Extrinsic
Intrinsic
What is the difference between the two coagulation pathways
Extrinsic is very fast and factors are released by tissues
Intrinsic factors are found only in the blood
What is the Common Pathway?
Where the two coagulation pathways converge
What substance is essential for coagulation?
Calcium (CA2+)
In which coagulation pathway is Factor VIII found?
Intrinsic Pathway
Which factors do platelets release in the Intrinsic Coagulation pathway?
Factor XII
Factor XI
Factor IX
Factor VIII
What factors do damaged tissues release during the extrinsic coagulation pathway?
Thromboplastin
Factor VII
What is Factor III otherwise known as?
Thromboplastin
What is Factor II otherwise known as?
Prothrombin
What is Factor I otherwise known as?
Fibrinogen
What is Factor IV otherwise known as?
Ca2+
What is Factor IX otherwise known as?
Christmas Factor
What is Factor VIII otherwise known as?
Anti-haemophiliac Factor A
What is the significance of Coagulation factor numbers?
They are numbered in the order they were discovered
What is fibrinolysis?
Dissolving of a blood clot
What is plasmin?
A fibrin dissolving enzyme or clot buster
What eventually causes clotting to stop?
Platelets produce clot inhibiting chemicals
Heparin etc inhibit clotting action
Do platelets stick to smooth vessel walls?
No
Why is rapid blood flow important in prevent clots?
Clotting factors are normally diluted by rapid blood flow
What can be a side effect of slow blood flow?
DVT
What are the natural anti-coagulants present in blood?
Anti-thrombin
Heparin
Where is Anti-thrombin produced in the body?
Liver
Which cells secrete Heparin?
Basophils
Mast Cells
How does Heparin act as an anti-coagulant?
It inhibits the action of thrombin preventing it converting fibrinogen into insoluble fibrin
On which chromosome is the gene that determines blood type?
Chromosome 9
What are the main blood groups?
A
B
AB
O
What is the Rhesus Factor?
Discovered in Rhesus monkeys
A type of antigen
85% of people have Rhesus antigen
15% do not and are therefore capable of making anti-rhesus antibodies
Why can blood group A not receive blood from group B
Because the antigen A will generate anti-body B in response to the foreign cell leading to illness and death.
Why can blood group A receive a donation from blood group A?
Because it’s own cells contain antigen A, they are not capable of developing Antibody A so preventing any attack.
Why is Group O sometimes referred to as the universal Donor?
A, B, AB and O can all receive blood from group O because it doesn’t contain any antigens
What is the split of blood groups across the population?
A - 44%
B - 9%
AB - 4%
O - 43%
What antigen is present on Rhesus positive Blood Cells
D Antigen
What will occur during a mismatched transfusion?
Agglutination
Haemolysis
Rhesus Positive Blood can only be given to Rhesus Positive individuals? True or False
True
O- blood can be given to any individual? True or False
True
What is Haemolytic Disease of Newborn?
Severe Anaemia
Toxic Brain Syndrome
Linked to Rh- mother and Rh+ baby
Why is it especially important for Rh- women to be aware of their blood type?
During their first pregnancy if the baby is Rh+ the blood from the baby may mix with the mothers blood leading to anti-d agglutinin production. Then for consecutive pregnancies if the baby is Rh+ they are at risk of developing Haemolytic Disease of the Newborn if the anti-d agglutinins mix with the foetuses blood.
What causes toxic brain syndrome in Haemolytic disease of the newborn?
Excessive Bilirubin
How is Haemolytic Disease of Newborn prevented?
Anti-D immunoglobulin given to mother during pregnancy, after delivery and within 3 days after birth
How many times a year is it safe to donate blood?
Three times
How much blood is it safe to donate at any one time?
500ml or 1 unit