Ch.17 Flashcards
Blood travels:
leaves arteries that branch until they become capillaries.
Bloods function:
carry oxygen, removes waste, transport metabolic waste, releases CO2. (Distribution, Regualtion, Body protection)
Blood pumped through:
pulmonary circuit (going to lungs) and systemic circuit (rest of body)
blood leaving heart is what type of blood vessels?
arteries. Returning to heart is veins.
Composition of blood:
plasma, formed elements (erythrocytes, leukocytes, platelets) and hematocrit
hematocrit
percentage of RBCs out of total blood volume
erythrocytes
red blood cells
leukocytes
white blood cells (buffy coat)
Blood structure:
sticky, opaque, scarlet (oxygen-rich) to dark red (oxygen poor)
blood distribution: (transportation)
oxygen to lungs, nutrients from digest. tract., metabolic wastes
regulation:
body temp by absorbing and distrib. heat, normal pH (7.45) in tissues, adequate water content in circulatory syst.
body protection
prevent blood loss, activating plasma proteins, clot formation, prevent infection (activating WBCs to fight against foreign material)
blood plasmsa:
protiens, albumin, globulins, fibrinogen (clotting proteins), hormones
gamma
immunity for defense
albumin
contributor to osmotic pressure. 60% plasma proteins
globulins (2):
(alpha, beta, gamma) transport proteins that bind to lipids. 36% plasma proteins.
formed elements (3):
erythrocytes, leukocytes, platelets
Erythrocytes :
(RBCs) No nuclei or organelles. (not complete) Filled with hemoglobin 97% (protein that functions in gas transport). Plasma membrane protein spectrin (felxibilty to change shape).
Erythrocytes function:
transporting gas, composed of protein globin (two alpha/ two beta chains) bound to heme group. Heme group bind to oxygen molecule.
Hemoglobin:
(transport up to 4 oxygen molecules.) O2 loading in lungs Produces Oxyhemoglobin (ruby red). O2 unload in tissues produce deoxyhemoglobin (dark red). Carbaminohemoglobin (CO2 loading in tissues)
Hematopoiesis
produce Red Bone Marrow of: Axial skeleton, Epiphyses. Hemocytoblasts give rise to form elemnts. Eventually form to RBC’s.
Erythropoiesis:
Production of blood cells. (homeostasis of RBCs). Balance of RBC.
Balance of RBC’s:
hormonal controls, adequate Iron, amino acids, B Vit.
Erythropoietin:
hormone, stimulating RBCs, Hypoxia (not enough RBCs)
RBCs die:
after 4 months. Lose shape, macrophages engulf them, spit them out, cellular debris. (can reuse) Heme and globin seperate. (Iron reuse).
Heme
degrade to bilirubin. Liver secretes into intestines where it metabolizes into Uribilinogen.
Globin
metabolized into amino acids and released into circulation.
never let monkeys eat bananas (most abundant)
neutrophils, lymphocytes, monocytes, eosinophils, basophils.
granulocytes (3):
neutrophils, eosinophils, basophils.
neutrophils:
pink, multiple lobes leukocytes. (PMNs). Hydrolizing enzymes and defensins. Bacteria slayers.
eosinophils:
red, lysosome like. specialize on infections from parasitic worms. lessen severity of allergies.
basophils:
U or S shaped. Histamine.
lymphocytes:
close to RBC size, nucleus take up most of cell. B lymphocytes give off antibodies.
Monocytes:
horse shoe shaped. Macrophages digest/ engulf. protect against parasites and infections.
platelets
blue staining outer region. HMPMP hemocyto-blast, megakaryoblast, promegakaryocyte, megakarocyte. –> platelets. Clotting mechanism.
hemostasis
forming blood clot. 3 steps: Vascular Spasm, Platelet plug formation, coagulation. (VPC)
vascular spasm (1):
smooth muscle contracts causing vasonstriction.
Platelet plug (2):
platelets release chemicals that make nearby platelets sticky and platelet plug fomrs.
coagulation (3):
(blood clotting). Fibrin forms a mesh that traps RBCs and platelets forming the clot.
coagulation:
prothrombin activator leads to clot formation. (after platelets/ mesh network). INTRINSIC (factors present inside blood) EXTRINSIC (factors outside blood). –> lead to prothrombin -> thrombin -> fibronogen ->fibrin-> cross linked fibrin mesh.
clot retraction:
stabilizes clot. Actin & myosin in platelets contract. (PDGF), fibrinolysis
Platelet-derive growth factor (PDGF):
rebuild blood vessel wall.
fibronolysis:
removes unneeded clot after healing.
thromboembolic disorders:
undesirable clot formation. (thrombus, embolus, embolism). Aspirin/ Heparin (blood thinners)
thrombus:
clot that develops unbroken blood vessels
embolus:
thrombus freely floating in blood stream
embolism:
embolus obstructing a vessel.
Thrombocytopenia:
deficient # of circulating platelets. (Petechiae -> hemorrhage due to destruction of red bone marrow)
Hemophilia:
Hereditary bleeding disorder, can’t generate platelets.
