Chapter 19: The Cardiovascular system Flashcards
How do cells obtain nutrients and remove wastes?
blood and interstitial fluid
What are formed elements
RBC’s (erythrocytes), WBC’s (leukocytes), platelets (thrombocytes)
What does blood transport?
- 02 & CO2
- nutrients
- wastes
- hormones
- heat
how does blood protect the body?
- protects against infection
2. produces antibodies
characteristics of blood
viscous
38 degrees celsius
pH: 7.35-7.45
What is a body’s hematocrit?
% measurement of body’s volume of red blood cells
blood consistency %’s
55% plasma
45%formed elements
- 5 % water
- 5 % solutes
protein components in blood
albumins
globulins
fibrinogens
non-protein components in blood
nutrients enzymes hormones respiratory gases electrolytes waste products
what do albumins do?
generate osmotic pressure (water in and out of blood vessels & interstitial fluid)
tyoes of globulins and what each does
alpha: transpo
beta: transpo
gamma: antibodies made from b lmphocytes
what do hematopoietic stem cells aka hemocytoblasts do?
form all blood cells
where do myeloid stem cells come from and what do they produce?
come from pluripotent stem cells and they produce erythroblasts, myeoblasts, monoblasts
where do lymphoid stem cells come from and what do they produce?
they come from pluripotent stem cells and produce lymphoblasts
what stimulates hemopoiesis and what does this process do?
stimulated by hormones and forms blood cells
what does erythropoietin do?
increases the # of RBS precursors
what does thrombopoietin do?
increases the # of platelet precursors
stimulate myeloid stem cells to deelop megakaryoblasts
which cells contain hemoglobin?
RBC’s aka erythrocytes
structural features of RBC’s
biconcave discs with no nucleus
whats the function of hemoglobin in RBC’s?
transpo 02 & CO2
what blood disorders arise when a body produces abnormal hemoglobin?
thalassemia, sickle cell anemia
sickle cell anemia
hemolytic anemia inherited due to abnormal hemoglobin
RBC’s destroyed which releases hemoglobin into blood
can be caused by parasite or drug reaction
symptoms: kidney damage, joint pain, fever
how long do RBC’s live?
120 days
how is hemoglobin recycled?
after phagocytosis of worn out RBC’s by macrophages
where does erythropoiesis occur?
adult red bone marrow of flat and long bones
what are the stages of development between hemocytoblasts and erythrocytes?
hemocytoblasts–> erythroblasts (rubiblasts)–> normobasts (with nucleus)–> reticulocytes (no nucleus)–> mature erythrocytes (no organelles)
what do erythroblasts capable of?
hemoglobin synthesis
what happens when normoblasts accumulate hemoglobin?
nucleus is fragmented
once reticulocyte has lost nucleus & mitochondria and has no ability to make protein it becomes an erythrocyte
which key hormone affects RBC production?
erythropoietin
anemia and its types
when 02 carrying capacity of blood is reduced
types: hemolytic (sickle cell), hemorrhagic, aplastic (iron-deficient, pernicious)
granular leukocytes
neutrophils, eosinophils, basophils, shows straining of cytoplasmic granules
agranular leukocytes
monocytes, lymphocytes, no granules
what are MHC (major histocompatibility antigens)?
surface proteins in leukocytes and erythrocytes that are used to identify tissue
lifespans of WBCs
hours or days
what occurs during leukocytosis?
increase in # of WBCs during infection or leukemia
leukopenia
abnormally low # of WBCs
what do leukocytes do?
combat inflammation & infection
what is emigration?
WBCs leaves blood vessel and goes to tissue
chemotaxis
chemical attraction of WBCs to a disease or injury site
what is diapedisis
blood cells squeezing through small holes in capillaries
structure and function of neutrophils
perform phagocytosis and produce defensins
multi-lobed nucleus
70% of WBC
what do defensins do?
pierce the membrane of pathogens in blood stream
is a natural antibiotic
structure and function of eosinophils
help with inflammation in allergic reactions (parasite)
red granules with headphone shape
1-3% WBC
structure and function of basophils
releases histamine, heparin, seratonin which intensify the inflammatory response
dark granules
1-5% WBC
total # of WBCs
5000-10000
what is heparin responsible for?
blood clotting at injury site
structure and function of lymphocyte (2)
large nucleus
B lymphocyte: differentiate into antibodies in response to antigens, develop in bone marrow
T lymphocytes: destroy antigens, develop in thymus gland, develop into macrophages when they leave circulation
differential WBC count
diagnostic test in which specific WBCs are listed
what do cytotoxic T cells do?
kills foreign cells by attaching and injecting with lymphotoxin
what does transfer factor do?
convert T lymphocytes to killer cells
what doe smacrophage chemotaxic factor do?
attracts macrophage to site of infection
helper T cells
help B cells form antibodies
suppressor T cells
inhibit antibody formation from B cells
memory T cells
cause faster response if the same antigen attacks body later
structure and function of monocytes
clean site of infection after neutrophils agranular U shaped nucleus develop from monoblasts form macrophages when leave capillaries 3-8% WBC
process of thrombopoietin
megakaryoblasts form into magakaryocytes which fragment–> each fragment (enclosed by cell membrane) has purple stain (granulomere) and blue stain (hyalomere)
what do platelet granules have that help blood clotting?
thromboplastin
what is hemostasis?
stoppage of bleeding in damages blood vessel
3 hemostatic mechanisms of hemostasis
vascular response, platelet response, plasma response
vascular response
smooth muscle of blood vessel wall contracts decreasing blood flow (loss)
platelet response
release of thromboplastin and seratonin accelerate the formation of a platelet plug
plasma response
blood clot is made when formed elements become trapped (possible bc of fibrin)
what are coagulation factors?
made, found, released by?
chemicals that clot
made in liver by vitamin K
found in blood plasma
released by platelets + damaged tissue cells
what initiated blood clotting?
extrinsic pathway (outside blood) intrinsic pathway (inside blood)
what is hemophilia?
inherited disease in which blood doesn’t clot
what is thrombis, thrombosis?
thrombis: clot in vessel
thrombosis: clotting unbroken vessel
embolis
clot that moves from origin
what are agglutinogens/isoantigens?
lie on surface of RBCs
genetically determined blood group antigens
what are agglutinins?
antibodies contained in plasma
either anti-a or anti-b
react with agglutinogens
what is hemolytic disease in newborns?
disorder caused by Rh incompatibility btwn mother/fetus
