Chapter 11 - Blood Flashcards
five functions of blood
- transportation of gases, nutrients, hormones, and wastes
- regulation of pH and interstitial fluids
- restriction of fluid losses at injury sites
- defense against toxins and pathogens
- stabilization of body temperature
formed elements
blood cells and cell fragments (platelets) suspended in plasma make up 45% of blood volume, 99.9% of which is RBC
erythrocytes
red blood cells transport oxygen life span of 120 days
leukocytes
white blood cells function as body’s defense mechanisms
platelets
small, membrane-enclosed packets of cytoplasm that contain enzymes and factors important to clotting remain in circulation for 9-12 days (thrombocytes)
whole blood
plasma + formed elements
fractionated
separation of blood
venipuncture
puncture of a vein to remove blood, instill a medication, or start an IV
plasma
Fluid portion of blood; 55% of volume; water accounts for 92% of plasma
albumins
-major contributors to osmotic pressure of plasma
-transport lipids, steroid hormones
-60% of plasma proteins
globulins
-transport proteins
-immune function (antibodies)
-35% of plasma proteins
-lipoproteins-involved in lipid transport
-can bind to lipids, fatty acids or cholestrol
fibrinogen
-essential component of clotting system; can be converted to insoluble fibrin to form clot
-4% of plasma proteins
immunoglobulins
antibodies attack foreign proteins and pathogens; produced by plasma cells of the lymphatic system
serum
the fluid left after the clotting proteins are removed
hemopoiesis
process by which formed elements are produced; liver and spleen are primary sites during development but in adults primary site is bone marrow
Hemocytoblast
-“pluripotent stem cells”
-produce myeloid stem cells and lymphoid stem cells
hemoglobin
-binds and transports oxygen
-accounts for over 95% of RBC’s intracellular proteins
-lack of hemoglobin = anemia
hematocrit
percentage of RBCs is 46 in males; 42 in females
heme
iron-based, pigment part of hemoglobin
anemia
reduced hemoglobin content
hemoglobinuria
large numbers of RBCs break down in circulation, urine can turn reddish/brown
biliverdin
a green bile pigment produced from hemoglobin breakdown; made when heme molecule is stripped of its iron
bilirubin
orange-yellow pigment made from biliverdin
transferrin
binds to iron in bloodstream and transports to bone marrow
Erythropoiesis
-production of red blood cells
-requires amino acids, iron, and vitamins (specifically B12, B6, and folic acid)
myeloid tissue
red bone marrow
erythroblasts
very immature red blood cells that actively synthesize hemoglobin (make hemoglobin)
reticulocyte
erythroblast that has shed its nucleus
-24hrs+ in circulation become indistinguishable from RBCs
vitamin B12
necessary for production of blood cells
type A blood
A antigens and anti-B antibodies
type b blood
B antigens and anti-A antibodies
AB blood
A and B antigens, no antibodies
universal recipient
O blood
no antigens, A and B antibodies
universal donor (most common blood type in US)
agglutination
clumping of red blood cells
granulocytes
A group of leukocytes containing granules in their cytoplasm; neutrophils, eosinophils, basophil
Agranulocytes
A group of leukocytes without granules in their nuclei; lymphocytes, monocytes
neutrophils
-50-70% of circulating WBCs; granules are chemically neutral
-usually the first RBC to arrive at an injury site
-active phagocytes; specialize in attacking bacteria
eosinophils
2-4% of circulating WBCs; stain from red dye = “eosin”attack antibody-labeled materials through release of cytotoxic enzymes and/or phagocytosis numbers increase dramatically during parasitic infection
basophils
smaller, rare (<1%)accumulate within damaged tissues, release heparine, histamine
heparine
prevents blood clotting
monocytes
2-8% of circulating WBC; twice size of RBC”free macrophages”; aggressive phagocytes
lymphocytes
20-30% of circulating WBCs provide defense against specific pathogens
leukopenia
Abnormally low white blood cell count
leukocytosis
excessive numbers of white blood cells
leukemia
cancer of white blood cells
lymphopoiesis
production of lymphocytes
thrombocytes
platelets
megakaryocyte
large platelet precursor cell found in the bone marrow
hemostasis
stoppage of bleeding
3 phases
-vascular phase
-platelet phase
-coagulation phase
coagulation
blood clotting
clotting factors
calcium ions, vitamin K and 11 different plasma proteins
intrinsic pathway
-activation of proenzymes
-proceeds with assistance of a platelet factor;
-after a series of linked reactions including Ca+
-clotting proteins form an enzyme capable of activating Factor X
clot retraction
after coagulation, platelets contract pulling torn blood vessel together
fibrinolysis
gradual dissolving of the clot
plasminogen
a plasma protein that is converted to plasmin by streptokinase
plasmin
converted from plasminogen by streptokinase; dissolves the fibrin of blood clots
endothelial layer
area of a blood vessel that is responsible for the majority of clotting
aspirin
inhibits platelet aggregation, antipyretic, blocks the formation of thromboxane A2
embolism
clots that move and suddenly block a blood vessel
Thrombi
blood clots
blood
connective tissue
pH of blood
7.35-7.45
-penia (suffix)
lack or deficiency
prothrombin
precedes thrombin; synthesized in the liver in a process that requires vitamin K
universal donor
O
