ch 8 circulatory system Flashcards
functions of blood
transportation of dissolved gases, nutrients, hormones, & metabolic waste
regulation of pH and electrolyte composition of interstitial fluids throughout the body
defense against toxins and pathogens
composition of blood
erythrocytes - red blood cells
thrombocytes - blood platelets
leucocytes - white blood cells
agranulocytes
lymphocytes
monocytes
granulocytes -
(polymorphonucleocytes)
basophils
neutrophils
eosinophils
plasma proteins
albumins - most abundant; transports lipids and steroid hormones; produced by liver
globulins - transports metal ions, hormones & lipids; gamma globulins are antibodies; produced by plasma cells (WBCs)
fibrinogen and prothrombin - clotting system
functions of plasma carried out by plasma proteins
colloid osmotic pressure (oncotic pressure) - colloidal plasma protein maintain higher concentration and form osmotic pressure preventing loss of plasma from blood and maintain volume
buffering - controls pH
lipoprotein complexes
high density lipoproteins (HDL) - most protein, some phospholipids, and least cholesterol from the cell
low density lipoproteins (LDL) - less protein, some phospholipids, and more cholesterol to the cell
very low density lipoproteins (VLDL) - least protein, most lipid for energy
chylomicrons - produced by intestinal absorptive cells which transport triglycerides, cholesterol, and phospholipids
erythrocytes (RBCs)
no nucleus, mitochondria, or organelles
regularly has access to glucose
packed with hemoglobin
live 110 days
globin contains 4 hems
20% of blood heart pumps needs to be filtered, remaining 80% pumping throughout body; filtered by the kidney
synthesis (erythropoiesis) occurs in bone marrow (gives signal to make more RBCs)
oxygen carried by iron while hemoglobin grabs carbon dioxide
hemoglobin
4 heme groups with iron, which reversibly binds to oxygen; hemoglobin can carry up to 4 oxygens
4 peptide chains; 2 alpha, 2 beta
leukocytes (WBCs)
contain nuclei and organelles
immune system / defense system
fewer than RBCs
found in connective tissue or lymphatic system which use blood for transportation
cytokines - most body cells when under attack can release a chemical ‘signal’
diapedesis - WBCs migrate out of bloodstream by squeezing between endothelial cells to make way to infection
** types of WBCs (5) **
neutrophils (most abundant)
lymphocytes
monocytes
eosinophils
basophils (least)
neutrophil
50-70% of circulating WBCs
segmented nucleus; polymorphonuclear leukocytes
first to arrive at site of injury
live shorter during infection as actively fighting
eosinophils
increase in numbers during parasitic infection and during allergic reaction
macrophage/endocytosis [grabbing whole thing to bring into cell] - combines into one big ‘monster’
live 8 - 12 days
basophils
smaller
discharges at injury site to enhance local inflammation:
histamine - vasodilator and
increaser of capillary
permeability
heparin - anticoagulant (blood
thinners)
swells area of injury
monocytes
circulate bloodstream for 24hrs before entering peripheral tissue to become a tissue macrophage (aggressive phagocyte)
2 main functions in immune system:
normal - replenish macrophages &
dendritic cells
inflammation signals - move quickly
to sites of infection and divide
into macrophages & dendritic
cells to elicit immune response
can live several days or months depending on activity
lymphocytes
2 main classes:
T lymphocytes - defend against
foreign cells and tissues;
coordinate immune response
B lymphocytes - produce and
distribute antibodies (proteins
that attack foreign molecules)
hemostasis
prevents blood loss from damaged small vessels; maintains blood volume
if blood vessel has leak, losing blood pressure; heart cannot adequately pump to body extremities, damages tissue
fibrinogen turns into fibrin
fibrin - holds blood platelets
together in place until tissues are
healed and are rebuilt
