Blood Flashcards
Globulins
Transport proteins; antibodies
Albumins
transport proteins dissolved in plasma
Fibrinogen and clotting factors
fibrinogen is a clotting protein dissolved in plasma. clotting factors are other chemicals needed for clot to happen
Serum
plasma with fibrinogen and clotting factors removed
Regulatory substances
chemicals used for communication
Erythrocytes
red blood cell with a biconcave disk.
thick around rim, thin around center giving greater surface area
most plentiful of formed elements and function to transport oxygen and carbon dioxide
no nucleus, no DNA
do not move out of vessel unless broken. lifespan is 110-120 days
Leukocytes
white blood cell
prominent nuclei; must be stained to be seen
can move out of blood vessels into tissue
Granulocytes
Neutrophils, basophils, and eosinophils
contain small granules that show up when stained
Agranulocytes
Monocytes and lymphocytes
do not contain visible granules
Neutrophils
most common type of leukocyte
typically make up 40-70%
number of neutrophils rises in response to bacterial infections
Basophils
least common type of leukocyte
average from 0-2%
number of basophils in circulation tends to increase with allergies
primary function is to release histamine and heparin
Histamine
causes vessels to dilate increasing blood to an area and vessel walls to become more permeable
allows more leukocytes to move out of blood vessels into injured tissues more quickly
Heparin
anticoagulant
Eosinophils
make up 0-6%
granules stain orange to bright red
increase with parasitic infections and allergies
chemicals can be effective against large parasitic worms
Monocytes
largest of leukocytes
migrate to tissues where they become macrophages
function to phagocytize debris, microorganisms, foreign invaders
numbers increase with inflammation and viral infections
Lymphocytes
make up 20-50%
smallest of leukocytes
two of their subclasses are T cells and B cells
Thrombocytes
called platelets
cell fragments
outnumber leukocytes
Functions of platelets
secrete vasoconstrictors (chemicals that secrete vessel size)
secrete clotting factors to promote formation of blood clots
form platelet plugs
secrete chemicals to attract neutrophils and monocytes to sites of inflammation
destroy bacteria
secrete growth factors to stimulate mitosis
Hemopoiesis
blood production
3 types: thrombopoiesis, leukopoiesis, and erythropoiesis
continual process
Hemocytoblast
stem cell that is starting cell for each type of production
said to be pluripotent, which means it can become any of 7 types of formed elements
located in red bone marrow
must be stimulated to grow and divide
Myeloid hemopoiesis
production of all formed elements in the red bone marrow
Thrombopoiesis
production of platelets
begins with hemocytoblast
liver and kidneys produce thrombopoietin which causes hemocytoblast to become megakaryocyte
megakaryocyte breaks apart to become several platelets
Leukopoiesis
production of leukocytes
begins with hemocytoblast
lymphocytes and monocytes produce CSFs depending upon immune system challenge
different type of CSF for each type of leukocyte depending on need
Erythropoiesis
erythrocyte production
begins with hemocytoblast
kidneys produce erythropoietin to stimulate RBC production when hypoxemia is present
negative-feedback response
Causes of hypoxemia
high altitudes
exercise
exposure to carbon monoxide
blood loss
Hemoglobin
red protein made of four chains of amino acids called globins
each chain contains heme group w/iron at its center
each hemoglobin molecule can carry 4 oxygen moelecules
Nutritional requirements for erythrocyte
iron is most necessary (meat, eggs, vegetables and legumes)
folic acid (orange juice and vegetables,) and vitamin B12 (meat/dairy)
copper (seafood, organ meats, legumes,) and vitamin C (fruits and green vegetables)
Life cycle of RBC
liver and spleen function to remove old RBC
heme broken down to iron and bilirubin
liver secretes bilirubin in bile, spleen secretes bilirubin into blood for kidneys to remove with urine
Sickle cell trait/disease
recessive gene that codes for different form of hemoglobin, causing RBC to change shape and sickle (forms crescent with points)
one copy results in sickle cell trait, usually not harmful
two copies result in sickle cell disease, fatal if not treated
beneficial to those living in malaria plagued areas
Hemostasis
means “the stopping of bleeding”
3 step process that happens in order
vascular spasm, platelet plug formation, blood clotting (coagulation)
3 steps of hemostatis
vascular spasm: constriction of broken vessel reducing blood flow
platelet plug formation: if vessel is broken collagen fibers are exposed on broken edges causing platelets to stick and form platelet plug
coagulation: dissolved fibrinogen forms solid fiber called fibrin, which acts as a net to trap RBCs and platelets to form solid clot
3 ways vascular spasm is initiated
pain receptors in injured tissue can stimulate vessel to constrict
platelets in broken vessel can release vasoconstrictors
injury to smooth muscle of a vessel wall can cause vessel to constrict
Pathways of blood clotting
intrinsic: started by platelets, slower than extrinsic
extrinsic: begun by damaged tissues, faster (15 seconds)
both require calcium, clotting factors, and lead to common pathway
Reaction cascade
during pathways of coagulation, each step activates next step for activation of inactive forms of clotting factors
Clot retraction
once a clot is formed, platelets shrink to draw edges of broken blood vessel together
Fibrinolysis
process by which plasmin dissolves unnecessary blood clot
Inappropriate clotting
platelet repulsion: lining of vessels prevent platelets from sticking
dilution: circulation of blood keeps thrombin diluted reducing ability to change fibrinogen to fibrin
anticoagulants: chemicals that interfere with pathways of clotting
Functions of blood
transporation
protection
regulation
Normal pH of blood
7.35-7.45
lower is acidic, higher is alkalinic/basic
Hematocrit
measures percentage of RBCs to whole blood
- 8%-46.4% in males
- 4%-44.4% in females
Hemoglobin test
amount of hemoglobin molecules in a given amount of blood
- 3-16.2 g/dL of blood for males
- 0-15.8 g/dL of blood for females
RBC count
- 30-5.60 million per cubic mm for males
4. 00-5.20 million per cubic mm for females
WBC count
3,540-9,060 mm cubed
Leukocytosis
high WBC count
Leukemia
also high wbc count, but the WBCs in leukemia are immature and unable to fight infection/pathogens
Leukopenia
low WBC count
Polycythemia
too many cells in the blood
Primary polycythemia
cancer of the blood
Secondary polycythemia
RBC count ranges from 6-8 million per mm cubed of blood
can result from dehydration, lowering ratio of plasma to formed elements, accelerated erythropoiesis, etc
Anemia
disorder resulting from insufficient RBCs or hemoglobin to carry enough oxygen to maintain homeostasis
Inadequate erythropoiesis/hemoglobin production
may be caused by inadequate iron in diet (iron deficiency anemia) or lack of intrinsic factor from stomach that allows vitamin B12 to be absorbed (pernicious anemia)
(hypoplastic or aplastic anemia as well)
Excessive bleeding (hemorrhagic anemia)
may be caused by trauma, failure to clot, or ulcers
RBC destruction (hemolytic anemia)
may result from drug reaction (penicillin allergy) or blood incompatibility (hemolytic disease of newborn)
other causes include inherited factors (sickle cell disease) or parasitic infections (malaria)
Hemophilia
inability to clot
sex linked disorders, mostly occurring in males
Thrombocytopenia
low platelet count (less than 150,000/mm cubed of blood)
one sign is excessive bruising after minor trauma
Disseminated intravascular coagulation (DIC)
widespread coagulation of blood in unbroken vessels
may be caused by systemic infection (septicemia) or if blood flow significantly slows as in cardiac arrest
