Blood Flashcards
Hematocrit
(percentage) of RBC’s in a volume of blood
hyperemia
increased bloodflow
characteristics of blood
- > specialized connective tissue
- > primary function = substance distribution
- > composed of blood cells suspended in blood plasma
how is blood a non-newtonian fluid
(a fluid whose viscosity changes based on applied stress or force; magic sand)
- > it’s both a solid (cells) and a liquid (plasma)
composition of blood blasma
90% water
10% solutes which include
- > respiratory gases
- > albumin
- > globulin
- > clotting proteins
- > amino acids
- > hormones
- > nutrients and electrolytes
- > metabolic enzymes
hematocrit of males vs females
Males
0.40 - 0.50 (40-50%)
Females
0.37 - 0.46 (37-47%)
What are reticulocytes and they make up what % of total RBC
they’re immature RBC that are found in the bone marrow and they mature in the bloodstream
- > makes up 1.0-1.5% of total RBC count
What is Hemoglobin? How much is in a males blood compared to a female
oxygen/CO2 carrying molecule
Males
- > 140-165 g/L
Females
- > 120-150 g/L
characteristics of erythrocytes
AKS RBC
- > no nuclei or orgnanelles (not “true” cell)
- > primarily for respiratory gas exchange
- > contains hemoglobin
- > makes up around 45% of total blood volume
explain the structure of RBC and how conformation can affect the cell
the shape of RBC’s are maintained by proteins, especially spectrin inside the inside of the RBC plasma membrane, which allows for RBC flexibility
- > continuous deformation for RBC to fit through small capillaries leads to an accumulation of membrane damage, which eventually triggers cell destructions/apoptosis
hematopoisis
also known as hemopoiesis
blood cell formation
- > occurs in red bone marrow
explain hematopoietic stem cells
also known as hemocytoblasts
all formed blood cells arise from the same type of stem cells (hematopoietic stem cells)
- > pleuripotential; stem cells that can only become certain types of cells
leukocytes
non-specific immune cells; white blood cells
- > basophils
- > neutrophils
- > eosinophils
- > monocytes
- > lymphocytes
what determines whether a pleuripotent stem cell will become a lymphoid stem cell or a myeloid stem cell
hormonal and chemical messengers control cell differentiation

formation of erythrocytes
- controlled by the hormone erythropoietin which is produced by the kidneys
- > the trigger for the response which releases erythropoietin is through monitoring of blood gases at the renal level - the hormone is released into the blood and travels to bone marrow and stimulates the formation of erythrocytes
describe the first few days of a erythrocytes
- > during a 3-5 day period, pleuripotent stem cells go through a few differentiations in the bone marrow (controlled by hormones) to produce an immature RBC (reticulocyte)
describe the process of erythropoisis
- > hemoglobin synthesis and iron accumulation occurs
- > degredation of the nucleus and ejection of MOST organelles occurs
- > the reticulocyte will then mature into a functional red blood cell in the bloodstream over the course of 2 days
- > erythrocytes are formed from reticulocytes and all remaining ribosomes and organelle structures will be destroyed
reticulocyte
immature red blood cell which develop in bone marrow and mature in the bloodstream
lifespan of a erythrocyte
around 100-120 days
why is a small amount (around 1%) of circulating erythrocytes prematurly destroyed and replaced everyday
they become trapped in the small blood vessels of the spleen (major blood filtration system) and liver and are degraded through normal apoptosis process
products of degraded erythrocytes
- iron
- > transported by blood plasma and stored in the liver
OR
- > transported to the liver and excreted through bile (if iron levels are sufficient/excessive)
2. heme - > degraded to biliruben which is sent to the liver and is released into bile, then converted into urobilinogen and excreted in feces or urine
3. globin - > broken down into amino acids (used for protein syn.)
characteristics of leukocytes
white blood cells
- > complete cells
- > primarily for body defense (immune activity)
- > WBC production can be increased when needed
- > carried mainly in loose connective tissue (blood) and/or lymphoid tissues (lymph nodes)
Classes of leukocytes
Granulocytes
- > neutrophils, eosinophils, basophils
Agranulocytes
- > lymphocytes, monocytes
Neutrophils
type of granulocyte
- > most numerous of the WBC (around 47-63%)
- > destroys bacteria through the production and release of oxydizing substances (i.e. H2O2) along with the release of defensin
- > attracted to inflammation (damage to cell tissue initiates inflammation)
Defensis
a protein that penetrates and pierces holes in bacterial membranes
Eosinophils
- > leads the attack on parasitic worms
- > plays a role in decreasing allergic reactions (phagocytose antigen-antibody complexes) and can inactivate some inflamatory chemicals (prevening widespread inflammatory response)
- > resides in loos connective tissue and releases enzymes that can digest paracidic worms
Basophils
- > contains histamine (vasodialator/attracts other WBC during inflammation) within their granules
- > basophils bind to IgE (immunoglobulin E) to initiate histamine response
Monocytes/Macrophages
monocytes - > macrophages
- > the largest leukocyte
- > these differentiate into macrophages within the tissues
- > have the ability to destroy pathogens
Megakaryocytes/Platelets
- > MK occur through repeated mitosis of myeloid stem cells without cytokinesis (no splitting so cell keeps getting bigger and bigger)
- > after formation, cytoplasmic extensions (bits of MK that break off) are sent into the sinusoid
- > these extentions rupture and release platelets (key to initiating the formation of blood clots) into the bloodstream
sinusoid
specialized capillaries found in the bone marrow
Lymphocytes
T and B cells
- > part of specific immune response
- > range of 24-40% of total WBC count
origin and life of hematopoietic stem cells
- > originate in the yolk sac of the human embryo
- > they migrate to the liver, where hematopoiesis occurs during fetal development
- > after birth, the stem cells migrate to bone marrow and the pocess of hematopoiesis will soley occur in BM for the remainder of life
hematopoietic stem cells/ hematopoiesis
hematopoietic stem cells
- > stem cells that give rise to other blood cells
hematopoisis
- > this process; formation of blood and plasma cells
rate of erythropoiesis
around 2.5 million erythrocytes/ second
lifespan of agranular vs granular WBC
*not including the formation and storage of “clone” cells*
agranular WBC
- > 100-300 days
granular WBC
- > 12 hrs-3days (depending on what pathogen is present)
what stimulates the production of megakaryotes and platelets
a specific cytokinase, thrombopoietin is released from the liver and kidneys which stimulates the production of megakaryotes and platelets
What stimulates the production of Neutrophils, eosinophils and monocytes
neutrophils
- > the cytokine granulocyte colony-stimulating factor (G-CSF)
Eosinophils and monocytes
- > the cytokine granulocyte-conocyte colony-stimulating factor (GM-CSF)
When would it be beneficial to administer exogenous thrombopoietin or exogenous erythropoietin
thrombopoietin
useful for patients with decreased/low platelet concentrations
erythropoietin
useful for patients with low RBC count and poor oxygen carrying capacity
Explain the ABO blood typing system
antigens = surface molecules that can involve immune response

possible transfusion reactions
- recipient antibodies could attack donated blood (worst)
- antibodies in the donor plasma will attack recipients blood cells
- antibodies could form complexes (masses) with other antigens which will clog/stop blood filtrations of renal system, leading to increased renal pressure and kidney failure
whats the difference between Rh+ and Rh- blood
Rh- lacks the RhO protein and Rh+ has it
- > only around 15% of gen pop is Rh-
what are Rh proteins
a family of plasma membrane surface erythrocyte antigens
how can someone with Rh- blood be exposed to Rh+ blood
- during transfusion (rare)
- between mother and fetus
- > maternal blood sharing between mother and fetus occurs especially during childbirth
What will happen if a mother is Rh- and her 1st and second babies are Rh+
1st child
- > not usually an issue as it takes a while for a mother to produce sufficient anti-Rh+ antibodies
2nd child
- > the anti-Rh+ antibodies produced by the mother will treat the baby as a forign substance and destroy fetal blood cells
what are the two processes of blood clotting
- formation of platelet plug
- blood coagulation
blood stasis
that the blood is not flowing or circulating as optimally as it could to all parts of the body this causes clotting as blood has to be in continuous motion to maintain its viscosity
explain the process of blood clotting
- > blood clotting is initiated by the exposure of collagen within the walls of the blood vessel following BV damage
- > this exposure of collagen releases a specific clotting factor (vonWillebrand’s factor) which causes platelets to become more “sticky” and they adhere to the collagen of the damage site
- > once adhered, platelets release their secretory vesicles which result in further alteration of platelet surface (becomes even stickier)
- > this forms a platelet plug, which is the start of a true clot/thrombus
- > final thrombus is held together by fibrin
