Flashcards in Blood Deck (103):
Why is it important that blood has a high heat capacitance?
How many liters of blood are in men (on average)? Women?
5 liters for women
5.5 liters for men
What are the three separate layers of a blood sample that are seen when spun out? What percent of the blood are each?
Blood layer -42%
Buffy white coat -min
The blood is what percent of the body weight?
What are the three major categories of the components of plasma?
What the four categoeries of proteins in plasma? Which is found in highest concerntration?
What are the three types of cells in the blood in order of their abundance?
3. WBCs (basophil lowest)
What is serum? How does this compare to plasma?
Plasma without fibrinogens and other coagulation factors
What is a mEq?
mM of ion multiplied by its charge
What is the anion gap calculation?
[Na] - ([Cl[ +[HCO3])
What are the primary cations in the plasma? Interstitial fluids? Intracellular fluid?
Plasma = Na
Interstitial fluid = Na
Intracellular fluid = K
What are the primary anions in the plasma? Interstitial fluids? Intracellular fluid?
Plasma = Cl and HCO3
Interstitial fluid = Cl and HCO3
Intracellular fluid = HPO4/proteins
What is the normal range of the anion gap?
What does the anion gap measure?
The anions that are not measured
What is the reason for looking at the anion gap?
Looks for metabolic acidosis
What can cause an increased anion gap?
Acidosis (DKA, lactic/salicylic acidosis)
What causes an increased anion gap?
[HCO3] goes down d/t increase in acids
Can you have a normal anion gap with acidosis?
Yes, if Cl balances out the loss of HCO3 (or vice versa)
How does hypoalbuminemia affect the anion gap?
Decreases anion gap d/t retention of CL and HCO3
What is osmolality?
osmoles of solute / Kg of solvent
What is an osmole?
Moles of solute times the number of ions or particles upon its dissociation in solution
What are the five major determinants of osmolality?
Na, Cl, HCO3, BUN, and glucose
The molality of plasma is higher or lower than interstitial fluid? Why?
Slightly higher because the plasma contains proteins (albumin) that cannot cross the capillary membrane
What is the osmotic pressure?
Pressure produced by the plasma proteins
What is albumin?
Transporter for FFAs, Ca, Cu, steroids, bili etc
Loss of albumin leads to what?
What is the primary cause of colloid osmotic pressure? What percent does this contribute?
Albumin--70-80% of colloid osmotic pressure
What percent of plasma protein is made up of albumin?
What can cause hypoalbuminemia?
What can cause hypoalbuminemia?
What is the function of gamma-globulins?
What is the purpose of transferrin?
Binds free Fe (since free Fe is toxic)
Is free Fe toxic?
What is the function of haptoglobin?
Binds free Hb that can enter the plasma after the lysis of RBCs to transport it to the liver
Can Hb be excreted in the urine? Can Hb + haptoglobin?
Yes for Hb, it is small enough
No for Hb + haptoglobin
What happens to the HB/HP complex?
Macrophages in liver and spleen endocytose it to conserve Fe
What is the half-life of free haptoglobin?
What is half-life of haptoglobin when bound to HB?
What would happen to plasma Hb and haptoglobin levels during an episodes of increased intravascular hemolysis?
Decreased haptoglobin levels
Increased Hb levels
What happens to platelets when it binds collagen/ligands in the vessels?
Increases surface area through projections
What is the purpose of a blood smear?
Estimate the relative abundance of different cells (RBCs, WBCs, platelets etc), size,or color of RBCs
What is the stain used to a blood smear?
What is the term describing the normal color of Hb? Less colored?
What is hematopoiesis?
The process by which RBCs are formed
What is the life span of RBCs?
What is the source of hematopoiesis? (where is it)
Stem cell in bone marrow
Are the progenitor cells from the hematopoietic stem cells differentiated?
Not really, and one stays a stem cell
What are the two lineages of the hematopoietic stem cell?
How is the hematopoietic system regulated?
Whole bunch of growth factors working in a combinational fashion
Why is it important that the RBCs have a biconcave shape?
Increase surface area/volume ratio
Easily and reversibly deformable
Why is it important that RBCs are easily and reversibly deformable? What happens if they are not (like when they are older)?
Needs to pass through tiny passages in the spleen
If old, cannot, and thus endocytosed
What is the function of carbonic anhydrase in RBCs?
Enzyme facilitates that conversion of CO2 into HCO3
In what form do RBCs carry CO2?
What is the primary HB type in adults?
What are the four chains that comprise Hb?
What is the amino acid in the Hb that accepts H+ in the blood?
What is erythropoietin?
Growth factor that stimulates the production of RBCs
In what stage of development do immature RBCs lose their nucleus?
What are the four stages of RBC development?
How long do reticulocytes circulate for? An increase in this is indicative of what?
Increase = increase in erythropoiesis
Where is erythropoietin produced?
What is the stimulus for erythropoetin synthesis?
O2 levels in the kidneys
What are the 5 factors that decrease O2 delivery to the kidney?
1. Low blood volume
2. Low Erythrocyte numbers
3. Low functional HB
4. poor blood flow
5. Pulmonary disease
Why can chronic renal failure cause anemia?
Lack of erythropoietin
What are the two fates of old RBCs?
Lyse in circulation
Phagocytosed by macrophages in the liver and spleen
What happens to the protoporphyrin ring of the broken RBCs?
Converted to Bilirubin by liver
What happens to the Fe in Hb?
What is hematocrit?
% of total volume of RBCs per total blood volume
What causes high hematocrit levels?
High = Polycythemia or dehydration
Low = Anemia, overhydration, or malnutrition
What is the mean corpuscular (cell) volume?
Hematocrit %/RBC count
What is the normal ranges for MCV?
What is the mean corpuscular Hb [c] (MCHC)?
Hb x100 / Hematocrit %
What is the reference range for MHCH?
How can anemias be classified?
What are platelets?
Small nucleus-free fragment of megakaryocytes
How long do platelets last? What organ destroys them?
What activates platelet? What happens with activation?
When glycoproteins on the surface bind collagen and other factors at sites of injury
Activation = shape changes and secretions of clotting factors
Which WBC is found in the highest amount? Lowest?
Highest = PMNs
Lowest = Basophils
Why is are there more cations in the plasma, compared to the interstitial fluid?
What to plasma [K] if there is a significant amount of cell lysis? Why is this not problematic in the body? Where is it a problem?
Increases, but kidneys handle it
It IS a problem if there is blood cell lysis during the sampling process
Within any one compartment in the body (e.g interstitial fluid, intracellular fluid etc) is there a slight charge, or do the cations balance the anions?
What can diarrhea cause the anion gap to do? How?
Increase d/t loss of HCO3
How can you have an acidosis without an anion gap?
If Cl goes up as much as HCO3 goes down
What is the formula for calculating plasma osmolality?
2 [Na] + ([BUN] /2.8) + [glucose]/18)
What is the range of osmolality of blood?
285-295 mOsm/kg H2O
Why is there a 2 coefficient in from of [Na] in the equation for determining plasma osmolality?
Account for Cl that dissolves with it
Why do you divide the [BUN] and glucose?
convert to milliosmoles per kg
What does the lymphoid lineage of cells give rise to?
(all the lymphocytes)
What does the myeloid lineage of cells give rise to?
What are "colony forming units"?
Groups of lymphoid or myeloid progenitor cells
What are "blasts"?
Precursor cells of many types
What is the disorder where there are too many RBCs made?
What is the half-life of reticulocytes? Why is this important?
Useful for seeing how much new RBC synthesis is occurring
What do kidneys produce when they sense that O2 levels are low?
What is HIF-alpha?
A transcription factor that is constantly synthesized
What happens to HIF-alpha in the presence of oxygen? What does this cause?
An enzyme adds a hydroxyl group to a Pro residue, causing VHL to target it for degradation for the proteasome
A decrease in oxygen levels leads to a (increase/decrease) in HIF-alpha? How?
Increase d/t decreased degradation by proteasomes
What happens to platelets at the end of their life?
Destroyed by liver
What is the process of platelet formation?
What is the chemical that is secreted constitutively by the liver and bone marrow, and stimulate megakaryocyte-progenitor cells?
What are the progenitor cells that give rise to platelets?
What is the feedback mechanism for thrombopoiesis?
Increases in platelet numbers causes a negative feedback by binding to and degrading TPO