Vol.3-Ch.9 "Hematology" Flashcards
Where does blood cell creation (HEMATOPOIESIS ) differ in location from fetus to adult?
As a fetus it takes place in everywhere but the bone marrow (in the liver, spleen, lymph nodes, and thymus (extramedullary hematopoiesis). But by the 4th month the bone marrow begins to produce as well.
After birth the bone marrow becomes the primary blood cell production with the additional help of just the liver and spleen.
By adulthood, blood cell is ONLY created in the bone marrow (intramedullary hematopoiesis)
What is Hematopoiesis?
A process in which cellular components of blood are formed by the differentiation of a PLURIPOTENT STEM CELL.
Pluripotent stem cells can form _____ _____ ____ ____, which then in turn can form _____ ____ that ultimately mature into _____(6)
Pluripotent stem cells can form MYELOID MULTIPOTENT STEM CELLS, which then in turn can form UNIPOTENT PROGENITORS, that ultimately mature into WHITE BLOOD CELLS (all types) RED BLOOD CELLS, & PLATELETS
What role do the Kidney, Liver and Spleen play in blood?
The Kidneys (a to a lesser extent the liver) produce ERYTHROPOIETIN, the hormone responsible for red blood cell production.
The Liver removes toxins and produces many of the clotting factors and proteins in plasma.
The Spleen is an important part of the immune system and has cells that scavenge abnormal blood cells and bacteria.
What is the normal volume of blood, and how much of the overall body weight is that?
Blood mass is largely determines by ___ & ___?
Normally the body can handle about ____ loss of blood, but with compensatory factors in a young healthy adult the body can compensate successfully for a loss of _____ blood.
There is normally an average of 85mL of blood per Kg, and this normally equates about 6% of the body mass.
Blood mass is largely determines by the amount of Red cells and plasma volume
Normally the body can handle about 0.5L loss of blood, but with compensatory factors in a young healthy adult the body can compensate successfully for a loss of 25-30% of blood.
What are the 4 main components that make up blood?
- Plasma
- Red blood cells
- White blood cells
- Platelets
What % of plasma is water?
proteins?
electrolytes, gases, and chemical messengers?
Plasma is:
- 90-92% water
- 6-7% proteins
- 2-3% electrolytes, gases, and chemical messengers
What and where is Albumin?
What is it useful for?
Albumin is a large cell molecule that cannot pass in and out of the membranes easily which is good because its presence in plasma helps retain water for the capillaries through Osmotic Pull or Oncotic Pressure.
Adversely electrolytes can pass in and out with ease
Red blood cells are _____.
They contain hemoglobin which are comprised of 4 subunits called _____ that each bond to a _____.
When fully saturated a hemoglobin can carry _____mL of O2 ; the body uses up about _____ of O2 per Kg of body weight every MINUTE.
Red blood cells are biconcave disks that DO NOT have a nucleus.
They contain hemoglobin which are comprised of 4 subunits called GLOBIN that each bond to a HEME (iron containing molecule).
When fully saturated a hemoglobin can carry 1.34mL of O2 ; the body uses up about 4mL of O2 per Kg of body weight every MINUTE.
The lower the pH (more acidic) of blood the Oxygen Dissociation curves to the ____ meaning that it _____ O2 more easily.
The high the pH (more alkalotic) of blood the Oxygen Dissociation curves to the _____ meaning that it _____ O2 more easily.
The lower the pH (more acidic) of blood the Oxygen Dissociation curves to the RIGHT meaning that it GIVES UP O2 more easily.
The high the pH (more alkalotic) of blood the Oxygen Dissociation curves to the LEFT meaning that it HOLD ON TO O2 more easily.
What is the Bohr Effect?
It is the tendency of CO2 saturated blood to want to diffuse into the alveoli in the lungs, allowing the O2 breathed in the bond to the hemoglobin via the heme.
Likewise when the O2 saturated blood reaches the body tissues, the CO2 from the tissues wants to bind to the hemoglobin so it forces the release of O2 at the tissues.
(Remember that Hemoglobin has a higher affinity for CO2 than O2)
What are 4 different things that may affect the Oxygen Dissociation Curve? (or what affects hemoglobin’s oxygen affinity)
- pH
- PCO2
- Concentration of 2,3 Biphosphoglycerate
- Temperature
(high temps = lessened affinity for O2 ; lower temps = increase affinity for O2)
Hemoglobin has an ____ times more affinity for CO over O2.
Even if 1 CO molecule binds to a hemoglobin, how does that effect the other 3 O2 molecules.
Hemoglobin has an 200-250 times more affinity for CO over O2.
Even if 1 CO molecule binds to a hemoglobin, it alters the hemoglobin so that it holds on the O2 molecules also attached so that it is harder for them to be released.
What does a shift to the RIGHT on the Oxygen-Hemoglobin Dissociation Curve mean?
A shift to the LEFT means?
To the RIGHT = a DECREASE in hemoglobin’s affinity to O2
To the LEFT= a INCREASE in hemoglobin’s affinity to O2
What senses and stimulates the production of red blood cells (ERYTHROPOIESIS)?
What can cause a decrease in RBCs
RENAL CELLS sense hypoxia and then secrete ERYTHOPOIETN (hormone) to stimulate the bone marrow to start producing more RBCs.
Hemorrhaging, hemolysis (destruction of RBCs), or Sequestering of RBCs can all decrease the count of RBCs
What contains cells that will scavenge and remove damaged or abnormal red blood cells? what are the cells called?
The Liver and Spleen have MACROPHAGES that are specialized white blood cells that will scavenge and remove damaged or abnormal red blood cells.
What are the 3 ways that you can measure the amount of RBCs?
- You can take the RBC count in millions per cubic millimeter (mm^3) which gives the total body count of blood ; usually measures between 4.2-6 million/mm^3
- Hematocrit is the packed cell volume of RBCs per unit of blood. Taken by putting a sample of blood in a test tube and putting it in a centrifuge. Since RBCs are the heaviest blood component (b/c of the iron containing molecule heme in hemoglobin) it will sink to the bottom leaving a thin line of white blood cells separating the RBCs and the plasma (on top). You then take the percentage volume of RBCs against the total volume in the tube and get a % which is normally between 40-52%
- you can also take a measurement of Hemoglobin present which is normally 12-15g/dL in men and is 10.5-14g/dL in women
White blood cells can move very freely in blood but some choose not to and would rather adhere to vessel walls until they are called upon. These are called ____ leukocytes. Other stimulate chemical or immune responses.
White blood cells can move very freely in blood but some choose not to and would rather adhere to vessel walls until they are called upon. These are called MARGINATED leukocytes. This property also allows them to squeeze through vessel walls (via DIAPEDESIS) to follow chemical messengers (CHEMOTAXIS) directly to an area of infection.
White blood cell count is normally _____ but can rise up to _____ per microliter of blood. Insinuating an infection is present,
White blood cell count is normally 5k-9k but can rise up to 16k per microliter of blood. Insinuating an infection is present,
White blood cells originate in bone marrow from Undifferentiated stem cells through LEUKOPOIESIS which respond to specific growth factors that allow them to differentiate into what 3 categories?
- Granulocytes
- Monocytes
- Lymphocytes