Cardiovascular II Flashcards
(124 cards)
Functions of blood
-transport dissolved gases, nutrients, hormones and metabolic wastes
-regulating pH, ion composition of interstitial fluids
-restricting fluid loss at injury sites by clotting
-defending against toxins and pathogens
-stabalizing body temp`
characteritistics of blood
-38 degrees
-high viscosity
-slightly alkaline
whole blood
-plasma + formed elements
plasma
-mostly water
-contains dissolved plasma proteins and other solutes
-similar in composition of interstitial fluid because water and ions
plasma proteins
-albumins
-globulins
-fibrinogen
albumin
-transport of FA, thyroid hormones, some steroid hormones
-major contribtors to plasma osmolarity
globulins
-antibodies
-transport gloobulins incluidng hormone binding proteins, lipoproteins and steroid binding proteins
fibrinogen
-soluble protein that functions in clotting
-fibrin is the insoluble form of fibringogen
formed element
-RBC
-WBC
-cell fragments
hemopoiesis
-process of producing formed elements
red blood cells
-99% of the formed elements
-contain hemoglobin that transport O2 and CO2
-dont have nuceluas, mitochondria or ribosomes
hematocrit
-percentage of blood sample that contains RBC
packed cell volume
-percentage of blood that contains all formed elements
structure of RBC
-small, highly specialized
-biconcave
important effects of RBC structure on function
-large SA:V ratio to quickly absorb and release oxyen
-stacks of RBC called roleux that smooth blood flow through vessels
-can bend and flex when entering small capillaries
hemoglobin
-proteins that transport respiratory gases
-four subunits: each contain 1 heme, 1 iron and each heme can bind to one O2 molecule
oxyhemoglobin
-hemoglobin bind/loaded with oxugen to form oxyhemoglobin
deoxyhemoglobin
-hrmoglobin and oxygen dissociated and unloaded to form deoxyhemoglobin
anemia
-results when hematocrit or Hb content of RBC’s is reduced
-interferes with oxygen delivery to peropheral tissues
erythropoeisis
-RBC formation
-in adults it occurs in myeloid tissue of certain bones
-a reticulocyte is a immature RBC thate scapes from bone marrow into blood
erythropoeitin
-when oxygen in peripheral tissues is low, kidneys secrete Eythropoeitin
-stimulates erythropoeisis
hemoglobin recycling
-macrophaes enguld aged RBC
-remove Hb molecule from ruptured RBC
-breach Hb down into iron and other components
-iron is removed and formed into biliverdin
-biliverdin is converted to bilirubin
-bilirubin is excreted by liver in bile
when iron is removed how is it transported/stored
-is bound and stored in phagocytotic cell or released into bloodstream
-in bloodstream iron is bound to transferrin
transferrin
-in developing RBCs in red bone marrow absorb transferrings and use them to synthesize Hb
-excess transferrins are removed in liver and spleen storing iron in ferritin and hemosiderin