Blood • Blood can actually be considered one of your body’s tissues . – Formed elements • all the blood cells – red blood cells (RBCs) (erythrocytes) » transport O 2 – white blood cells (WBCs) (leukocytes) » immune response • and the platelets – membrane sacs that help seal broken blood vessels – Plasma • proteins used for blood clotting and osmotic pressure • Serum » nutrients (glc, aas, fats) » waste (mostly urea) » dissolved gases (O 2 , CO 2 , N 2 ) » electrolytes (Na + , K + , Cl - )
Blood. Blood can actually be considered one of your body’s tissues . Formed elements all the blood cells red blood cells (RBCs) (erythrocytes) transport O 2 white blood cells (WBCs) (leukocytes) immune response and the platelets membrane sacs that help seal broken blood vessels Plasma - PowerPoint PPT Presentation
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Blood• Blood can actually be considered one of your body’s tissues.
– Formed elements
• all the blood cells
– red blood cells (RBCs) (erythrocytes)
» transport O2
– white blood cells (WBCs) (leukocytes)
» immune response
• and the platelets
– membrane sacs that help seal broken blood vessels
– Plasma
• proteins used for blood clotting and osmotic pressure
• Serum
» nutrients (glc, aas, fats)
» waste (mostly urea)
» dissolved gases (O2, CO2, N2)
» electrolytes (Na+, K+, Cl-)
Blood
Blood - hemopoiesis• production of blood cells
– erythropoiesis -RBCs
• kidneys produce erthropoietinwhen O2 levels drop
• new RBCs produced inred bone marrow
• negative feedback loop• production of blood cells
– leukopoiesis -WBCs
• triggered by infections or other attacks on the body
• production of blood cells
– leukopoiesis -WBCs
• triggered by infections or other attacks on the body
Blood - hemopoiesis• production of blood cells
– erythropoiesis -RBCs
• kidneys produce erthropoietinwhen O2 levels drop
• new RBCs produced inred bone marrow
• negative feedback loop
• production of platelets
– thrombopoiesis
• megakarocytes
– bone marrow
– lungs
• pinches off pieces of cytoplasm
Blood - erythrocytes• Red blood cells transport O2
(and some CO2)
– hemoglobin
• 4 protein chains (globins)
– 2 alpha chains
– 2 beta chains
• 4 heme groups
– site where O2 molecules bind
• Polycythemia
– too many red blood cells
• increase blood volume
• increase blood viscosity
• increase blood pressure
– heart over worked
– can lead to embolism, stroke, heart failure
• Anemia
– too few blood cells carrying O2
– hemorrhagic anemia - excessive blood loss
– hemolytic anemia - destruction of RBCs or too little erythropoiesis
– sickle-cell anemia and thalassemia
• both caused by abnormal hemoglobin
Blood - erythrocyte disorders
• All cells have membrane proteins that label the cell as “friend” or “foe” to the immune system
– antigens
– allow your immune system can differentiate your body cells from foreign or infected cells
• Antigens on RBCs called agglutinogens
– react with antibodies in blood called agglutinins– mismatched transfusions cause agglutination (transfusion reaction)
• agglutinins bind toagglutinogens and linkRBCs together
• cause RBCs toform “clumps” (agglutination)
Blood Types
• ABO blood groups
– type A and type B agglutinogens (antigens)• just A type agglutinogens - type A blood
• just B type agglutinogens - type B blood
• both agglutinogens - type AB blood
• no agglutinogens - type O blood
– transfusion rxns can occur because you also have agglutinins (antibodies)
• type A blood - antiB agglutinins
• type B blood - antiA agglutinins
• type AB blood - no agglutinins
• type O blood - both agglutinins
Blood Types
• ABO blood groups
– type AB blood• no agglutinins - sometimes called universal recipient
• what about agglutinins in donor’s blood?
– type O blood - both agglutinins• no agglutinogens - universal donor?
• But has both types of agglutinins
Blood Types
• Rh group
– Rh+ have the Rh agglutinogen– Rh- do not have Rh agglutinogen
• will produce antiRh agglutinin if exposed to Rh+ blood
Blood Types
• Rh- Mom exposed to Rh+ blood of newborn at birth
• no problem during first pregnancy
Blood Types - hemolytic disease of the newborn (HDN)
• Mom produces antiRh agglutinins
Blood Types - hemolytic disease of the newborn (HDN)
• Mom’s antiRh agglutinins attack Rh+ RBCs of fetus in next pregnancy
Blood Types - hemolytic disease of the newborn (HDN)
• Can be prevented by treating with RhoGAM
Hemostasis• The stoppage of bleeding (3 ways)
– 1) Vascular Spasm• constriction of the injured blood vessel via:
– pain receptors
– smooth muscle damage
– serotonin (released from platelets)
– 2) Platelet plug formation• platelets react with collagen