Composition and features of BLOOD Flashcards
Describe Blood circulation
vast amount of tiny capillaries- high pressure to force blood through
large vessels- high v / low F
small vessels Low V/ High F.
Describe what Blood pressure ensures
even and efficient flow through the small capillaries
low enough to present capillary leakage but high enough to avoid coagulation
What are the 7 Major components of blood
cells proteins lipids electrolytes Vitamins, hormones Glucose
state Blood ‘cells’
Erythroid, myeloid, lymphoid
state Protein cells in blood
albumin, haemoglobin, fibrinogen, immunoglobulin
State the lipid cells
bound in lipoproteins HDL, LDL, VLDL
State the Electrolytes
salts and minerals ( HCO, NA, CI, CA, MG, K, creatine
State the Major blood proteins
Albumin
Fibrinogen
Describe ALbumin
Major blood protein
Maintains colloidal osmotic pressure.
binds and transports main small molecules and hormones
Describe Fibrinogen
7% of total blood protein
activated through the coagulation cascade to form cross linked fibrin
Fibrinogen—– Fibrin
What are immunoglobulins
Antibodies. Diverse range of antigens binding proteins- produced by B lymphocytes
What is Complement
9 proteins that coat bacteria targeting them for phagacytosis. C3 is a major component
What are Coagulation factors
13 proteins cleaved in an ordered cascade resulting in fibrogen—- fibrin.
CA is essential to coagulation.
What is HAemophillia
results from a missing component. Factor 8 deficiency is the commonest form of haemophillia
Describe electolytes
Istonicity and buffering. Blood pH is tightly maintained at 7.4.
Describe the electrolytes which are tightly monitored
Free Ca++
K+ are tighly maintained. Most important
They are critical for regulation of cell membrane channels, ion pumps and normal nerve and muscle function such as heart
What are the innate blood cells
Basophils
Eosinophil
Neutophils
monocyte
Macrophage
what are the adaptive blood cells
small lymphocyte
t lymphocyte
b lymphocyte
plasma cells
State the three factors that drive haematopoiesis
GM- CSF : Granulocyte macrophage colony- stimulating factor
EPO- Erythropoietin
G- CSF- Granulocyte colony stimulating
Describe GM- CSF
Produced by macrophage, T cells, endothelial cells and fibroblasts
stimulates the production of
neutrophils, eosinophils, basophils and monocytes
Describe EPO
drives the production of erythrocytes
produced mainly by the kidney during adulthood and liver in perinatal
Describe G-CSF
Stimulates production of granulocytes but also acts to mature neutrophils
Describe Hemoglobin and oxygen transport
association and dissociation of O2 from heme is regulated by the partial pressure of O2
eg: O2 readily associated in the lungs and dissociates in the tissues
Why do cells need O2
energy= oxidization
What is complement essential for
complement is a proteolytic activation cascade and is essential for innate immunity.
What is C3
most abundant complement component in serum
attaches to the bacteria by a covalent bond
How is complement activated
The classical pathway is mediated by antibodies IgM or IgG binding to a microbe surface which is then bound by complement C1
What is opsonisation
Very first activation in infection.
Soaking of a bacteria in complement enables you to recognize bacteria as nonself
describe convertases
Desposited complexes are called convertases. These activate more complement that then deposits to coat the surface
How are convertase bound
irreversibly bound through a covalent bond
What occurs during with C3, C4 and C5
they all produce small fragment (C3a, C4a and C5a) that are powerful chemoattractant called anaphylotoxins that attract and activate neutrophils.
C5a is the most important
What occurs to people who lack complement
They are susceptible to chronic infections
Describe factors that influence the complement cascade
Many microbes produce proteins called virulence factors that inhibit the complement cascade.
Describe coagulation
Proteolytic activation cascade
there are two pathways for activation
- Intrinsic caused by contact with surfaces
- Extrinsic caused by tissue damage
What is Factor X
Is a key enzyme in coagulation
it is common in the 2 pathways (extrinsic and intrinsic)
Calcium’s involvement with coagulation
essential at a number of steps. Remove calcium and blood does not clot
Thrombins involvement with coagulation
A enzyme that claves fribrogen to fibrin which cross-links
Describe parasites involvement with coagulation
parasites and other microbes that rely on blood flow produce powerful anti coagulants that typically target the thrombin step
Describe Plasminogen in coagulation
Plasminogen is converted to active plasmin and dissolves the clot (thrombolysis)
Describe Plasminogen’s involvement with medicine
Plasminogen activates: TPA (Tissue Plasminogen Activator) or Strephtokinase are used widely in medicine for the treatment of thrombosis.
Carbon monoxide turns the blood which colour
cheery red
Cyanide turns the blood what colour
pink
