Lec 12- Blood composition and hemostasis Flashcards
Formed elements
cellular elements of the blood
Plasma
A medium for materials being carried in the blood.
90% water.
Albumin
1 of 3 large plasma proteins.
60-80% (7-9% of plasma)
Creates colliod osmotic pressure that draws H2O from the interstitial fluid into capillaries to maintain blood volume and pressure.
Globulin
carry lipids.
gamma globulins are antibodies found in blood.
Fibrinogen
when activated (as fibrin) serves as a clotting factor.
Fibrin
Activated, clotting factor.
Serum
Fluid left when blood clots
Chylomicron
From small intestine to Apo B-48.
Transport cholesterol and lipids form intestine to liver and tissues via blood.
LDL (low density lipoprotein)
From liver to Apo B-100.
Transports cholesterol and lipids form liver to tissue.
Too much is bad, leads to build up and plaque.
HDL (high density lipoprotein)
Tissue and blood vessels - Apo A-1.
Transport excess cholesterol from tissues and delivers it to the liver.
Hematopoiesis
formation of blood cells from stem cells in bone marrow
Erytrhocytes (RBC’s)
red blood cells
Erythropoeisis
formation of RBCs
Erythropoietin (Epo)
From kidneys, stimulates erythropoeisis
Bone marrow
creates new RBC’s
Heme group
iron core attracts oxygen
Folic acid
required for adequate DNA replication
B12
required for adequate DNA replication
Hemoglobin (Hb)
conatins heme group that carries Oxygen
Bilibrubin
Break down product of hemoglobin
ABO system
Blood types
Antigen
A substance (toxin, enzyme, or protein) that stimulates the production of antibodies.
Antibody
Attack antigens
Agglutinate/Agglutination
If different blood types are mixed, antibodies will cause mixture to agglutinate.
Universal donor
Type O
Lack A and B antigens.
Universal recepient
Type AB
Doesn’t make anti-A or anti-B bodies.
Rho(D)/Rh factor
Another type of antigen found on RBC’s.
Erythroblastosis fetalis
When Rh- mother has Rh+ babies.
Mom may be exposed to fetal Rh+ blood, first time.
In later pregnancies mom may produce Rh antibodies.
Antibodies cross placenta causing hemolysis of fetal RBC’s.
Leukocytes (WBCs)
WBC’s
Diapedesis/Extravasation
WBC, the ability to squeeze through capillary walls.
Leukopoiesis
a form of hematopoiesis in which white blood cells (WBC, or leukocytes) are formed in bone marrow located in bones in adults and hematopoietic organs in the fetus.
Megakaryocyte
its fragments form platelets
Thrombocytes/Platelets
smallest formed elements, constitute most of mass of blood clot
Granular leukocytes
Help detoxify foreign substances and release heparin.
Includes; eosinophils, basophils, and neutrophils
Eosinophils
1-3% of leukocytes.
Attack pathogens that cause allergies.
Basophils
1 % of leukocytes.
Release heparin.
Neutrophils
50-75% of leukocytes
Wrap around and phagocytize bad cells.
Agranular leukocytes
Either destructive and/or phagocytic or produce antibodies.
Include; lymphocytes and monocytes.
Monocytes - Macrophages
2-10%.
Become macrophages.
Phagocyte/Phagocytosis
Destroy multicellular substances.
Lymphocytes
Become either T or B cells.
Cell-mediated immunity
When T cells attack infected host cells, cancer cells, and foreign cells.
T cells
Do NOT secrete antibodies.
Attack infected host cells, cancer cells, and foreign cells.
Thymus
Develops T cells.
B cells
Mature in bone marrow.
Fight infections by secreting antibodies into blood and lymph.
Provide humoral immunity.
Humoral immunity
From B cells.
Fight infections by secreting antibodies into blood and lymph.
Hematocrit (~45%)
Packed cell volume.
Includes RBC’s, WBC’s and platelets.
Anemia
Hematocrit = 30%.
Polycythemia
Hematocrit = 70%
Buffy coat
Platelets and leukocytes
Hemostasis
cessation of bleeding.
NO (nitric oxide)
Keeps clots from forming and are vasodilators.
Keep platelets from sticking.
Collagen
Binds to platelets under the right circumstances to create clot.
von Willebrand factor
Damage to endothelium allows platelets to bind to exposed collagen.
Increases bond by binding to both collagen and platelets.
Platelet plug
ADP and thromboxane A2 cause other platelets to become sticky and attach and undergo platelet release reaction.
This constitutes until platelet plug is formed.
Plug contraction
When clot contains platelets, fibrin, and trapped RBC’s.
Platelet plug undergoes plug contraction to form more compact plug
Intrinsic pathway
clots damaged vessels and blood left in test tube.
Initiated by exposure to negatively charged surface of glass or blood vessel collagen.
Factor XII (Hageman factor)
Starts the intrinsic pathway.
Extrinsic pathway
Damage outside blood vessels releases tissue thromboplastin that triggers a clotting shortcut.
Tissue thromboplastin
Trigger clotting shortcut.
Very quick activation step.
Prothrombin
Ca 2+ and phospholipids convert prothrombin to thrombin.
Thrombin
converts fibrinogen to fibrin which polymerizes to form a mesh.
Kallikrein
When damage is repaied, activated factor XII (Hageman factor) cause activation of kallikrein, which is necessary to start the process to dissolve clots.
It converts plasminogen to plasmin.
Plasmin
digests fibrin, dissolving clot.
TPA (tissue plasminogen activator)
Tissue plasminogen activator.
Plasminogen can be converted to plasmin by kallikrein.
Ca2+ chelators
Anticoagulant.
Prevents clotting.
E.g. sodium citrate or EDTA.
Sodium citrate
Anticoagulant.
is a Ca2+ chelator.
Prevents clotting.
EDTA
Anticoagulant.
is a Ca2_ chelator.
Prevents clotting.
Heparin
Anticoagulant.
Activates antithrombin III (blocks thrombin)
Coumarin
Anticoagulant.
Type drugs block clottin indirectly reducing effects of Ca2+ (through Vit K pathway) which results in slower clotting times)
i.e. warfarin, coumadin
