Blood and Immune - Blood Composition and Function Flashcards
How much blood does the average person have?
5L
What is the volume of blood that circulates through the heart every 24 hours?
14,000 L
How many chambers are there in the heart and what are they called?
4
Left and right ventricle
Left and right atrium
What part of the heart brings blood to the lungs?
The pulmonary artery
What brings blood from the lung to the heart?
The pulmonary vein
What are arteries made of?
Muscular capillaries with elastic vessel walls that contain an abundance of smooth muscle.
This smooth muscle allows the artery to expand and constrict through an involuntary movement
Is blood pressure higher in veins or arteries?
Arteries
Why is venous blood pressure lower than arterial?
Because veins are not elastic
What is the functions of the valves in veins?
To prevent back flow
What is systolic blood pressure?
Highest blood pressure attained in arteries
Blood is at full compression
The left ventricle is squeezed at its tightest and the artery walls are expanded at their greatest
What is the purpose of blood?
Blood provides a one-way pressurised system for the transport of oxygen, proteins glucose, lipids and essential ions required for normal cell function.
What is normal blood pressure?
120/80
What does the 120 in blood pressure mean?
Your systolic blood pressure in millimetres of mercury (120mm up the tube measuring blood pressure)
What is diastolic blood pressure?
When blood pressure is at its lowest
What does the 80 in blood pressure mean?
Diastolic blood pressure
What is hypertension?
high blood pressure
What causes hypertension?
Arteries are not expanding and contracting effectively (hardened, blocked or disease) which reduces flow and resulting in unwanted coagulation
What is a high blood pressure
above 140-150
What is the result of low blood pressure?
not enough blood going through arteries to supply tissues with blood
Common symptom of low blood pressure
fainting
What is needed to retain blood pressure?
Blood volume
What loss of blood is fatal?
over 20% because pressure and flow is impaired and the result is tissue starved of O2
Why do we need blood pressure?
to ensure even and efficient blood flow through small capillaries, low enough to prevent capillary leakage but high enough to avoid coagulation.
Main components of blood
Cells, proteins, lipids, electrolytes, vitamins and hormones, glucose
Where do myeloid and lymphoid cells come from?
multipotential stem cells
What are the two types of lymphoid cells?
B and T cells
Where do B lymphocytes come from?
Bone marrow
What is the function of B lymphocytes?
They have antibodies/immunoglobulins that give adaptive immunity
Where do T lymphocytes mature?
In the thymus
What are the 3 main cells in blood?
Erythrocytes, leukocytes, thrombocytes
What is the function of Erythrocytes
to transport oxygen to tissue
How many Erythrocytes in the body?
5-6 million/ml
What is the shape of a Erythrocyte?
It is a flat disc that has no nucleus
What is the main protein in Erythrocytes?
Haemoglobin
What is the main function of leukocytes
immune defence
What is the most common leukocyte
Neutrophil
How many leukocytes are in the body
10,000/mL
What is the function of neutrophils?
respond immediately to microbial challenge like an infection, migrate quickly from capillary tissue to the site of infection, engulf the organism
What is the function of thrombocytes?
Coagulation and tissue repair
How many thrombocytes are in the blood?
400,000/ml
What is the size of thrombocytes
1/20th of a leukocyte
what do thrombocytes do when an injury occurs?
platelets link together as a part of the blood clot to block off wound to prevent leakage of blood or fluid from damaged tissue
What are the major proteins in blood?
Albumin, haemoglobin, fibrinogen, immunoglobulins
How much of blood protein is albumin?
50%
What is the function of Albumin
Maintains colloidal osmotic pressure and hyponeiticity, Binds and transports many small molecules, hormones.
How does Albumin maintain osmotic pressure?
It acts as a “Protein sponge” that absorbs fluid in blood and allows fluid to be balanced
What is the function of haemoglobin
to carry oxygen from heart to other tissues in red blood cells
How much of blood is fibrinogen?
7% of total blood proteins
What is the function of fibrinogen?
It is cleaved in coagulation cascade to form fibrin molecules which link to form a clot (prevent tissue leakage)
What are lipids bound in?
Lipoproteins
What are the main types of lipids?
LDL, HDL, VLDL
Which lipid is bad for you?
LDL
Why is LDL (lipid) bad for you?
LDL = low density lipid
If levels of LDL’s increase, it means that a build-up of cholesterol can build up in your arteries = heart attack
What are the major electrolytes in the blood?
HCO3 -, Na+, Cl-, Ca++, Mg++, K+, creatine, creatinine
What electrolyte is the most tightly regulated and why?
Potassium (K) because it regulates a lot of cellular functions like nerve potential and heart muscle activity
What is the normal blood ph?
7.4
How much variance can occur above/below blood pH before severe stress can occur?
0.2
What is acidosis?
blood is more acidic (pH decreases)
What is alkalosis
blood is more basic (pH increases)
What are Immunoglobulins ?
antibodies
What do Immunoglobulins do
Provide a diverse repertoire of antigen binding proteins
What is complement?
Proteins that “coat” bacteria targeting them for phagocytosis
What is the major complement component?
C3
What is opsonisation?
Irreversible coating of bacteria with complement so that phagocytes are attracted and can bind them.
What are first cells that go to site of infection due to complement?
Neutrophils
How many complement proteins are there?
9
Number of coagulation factors
13
What happens in a coagulation cascade?
13 proteins cleaved in an ordered cascade resulting in cleavage of fibrinogen -> fibrin (forms clot)
What electrolyte is essential to coagulation?
Ca+
What is the most common form of haemophilia?
Factor VIII (8) deficiency
What is haemophilia
Haemophiliacs blot does not clot (they can bleed to death from vascular leakage)
What is the function of electrolytes?
Isotonicity and buffering
What is centrifugation?
technique used to separate blood into its different components
What is added to blood before centrifugation what is its purpose?
An anticoagulant to stop blood clotting
Example of a anticoagulant?
Heparin
How many layers result from centrifugation?
3
What is the top layer of a centrifuge?
The plasma layer
What % is the plasma layer in a centrifuge
55%
What is the plasma layer?
Blood with fibrinogen present (ie has not clotted yet)
What is contained in the plasma layer?
Soluble proteins, lipids and platelets
What is the middle layer of a centrifuge?
The buffy coat
What is the buffy coat?
Layer of white cells
What is in the buffy coat?
Lymphocytes, myeloid and leukocytes
What is the bottom layer of the centrifuge?
Packed red cells
What % is the packed red cells
45%
What is anemia
You don’t make enough red blood cells
Symptoms of anemia
Difficulty breathing, become tired
What causes Cerebral Edema
Making too many red blood cells (happens normally by being at high altitudes, blood becomes viscous lead)
What is plasma
The viscous liquid fraction of un-coagulated blood without cells
What is contained in plasma
Fibrinogen (removed with coagulation)
Why can’t plasma be electorpheresed?
Fibrinogen causes problems
What is serum?
Less viscous yellow liquid remaining after the removal of the clot
What is serum electrophoresis?
Separating blood using an electric field
What are the five major protein fractions of serum electrophoresis
albumin, α1, α2, β and γ
What % of serum electrophoresis is albumin
50%
What % of serum electrophoresis is globulin? (albumin, α1, α2, β and γ)
40%
What is the γ fraction?
Where anti-bodes/immunoglobulins reside
is γ fraction + or -
Positively charged
So they migrate towards the negative electrode on serum electrophoresis
What is multiple myeloma?
A type of leukaemia
Aberrant B cell present and is producing antibodies in high amounts
Where do myeloma cells reside?
In bone marrow
Where do blood cells come from?
A single multipotent stem cell in bone marrow
Are multipotent stem cells rare?
yes
What do multipotent stem cells do?
differentiate into any other mature hematopoietic cells in the body
What surface antigen is on multipotential Hematopoietic stem cells
CD34
What do CD34 HSC divide into?
Myeloid and lymphoid progenitors
What does the myeloid progenitor divide into?
Other myeloid cell types
Consist of erythrocytes, thrombocytes, mast cells, myeloblasts, leukocytes
What does the lymphoid progenitor divide into?
Natural killer cells
Large lymphocytes, small lymphocytes which makes T lymphocytes and B lymphocytes (ie forms plasma cells)
What factors drive haematopoiesis?
GM-CSF, EPO and G-CSF
What produces GM-CSF
Macrophages, T-cells, endothelial cells and fibroblasts
What does GM-CSF stimulate?
Production of neutrophils, eosinophils, basophils and monocytes
What is the function of the GM-CSF factor?
Stimulate the myeloid lineage
How does GM-CSF factor work?
Receptors on the myeloid progenitor cells binds to GM-CSF which stimulates cells to differentiate further into myeloid cells
What produces EPO
Kidney = adulthood Liver = perinatal
What is the function of EPO
Signal production of Red Blood Cells
What type of factor is used in blood transplants?
EPO
What type of factor is the target of drug testing?
EPO
What does GM-CSF stand for
Granulocyte Macrophage Colony Stimulating factor
What does G-CSF stand for
Granulocyte Colony Stimulating Factor
What is the function of G-CSF
Stimulate production of granulocytes but also acts to mature neutrophils
What is the function of the lung in oxygen and transport exchange?
Provides a vast surface area for blood and consist of the alveoli for efficient exchange of O2 and CO2
Colour of blood in venous system
Dark red (lacks oxygen)
Colour of pulmonary blood
Bright red (spurts out due to pressure)
How much of your total blood volume is red blood cells?
45%
How much of your red blood cells dry weight is haemoglobin?
96%
What carries oxygen in red blood cells?
Protein haemoglobin
How many lobes are in a haemoglobin
4
What is contained in each lobe of a haemoglobin protein
A heme molecule
What is contained in each heme in a haemoglobin protein
An iron atom, ferrous form, Fe2+
What regulates the association and dissociation of O2 from heme
Partial pressure of O2
O2 readily associates in the lungs, dissociates in the tissues
Partial pressure of oxygen in the alveoli of the lungs
100mm Hg
Partial pressure of CO2 in the alveoli of the lungs
35mm Hg