Biomed Mod.15 obj.7-13

The flashcards below were created by user jnikrap on FreezingBlue Flashcards.

  1. Erythropoiesis
    • part of hematopoiesis, specifically relating to the production  and maturation of red blood cells
    • RBCs are produced continuously (approx. 2 million per sec.) to keep up with RBC destruction
  2. Hypoxemia
    • if the number of re cells lost exceeds the number made.(too little oxygen in the blood)
    • The lack of oxygen is not due to problems with breathing; there just isn't enough red cells to transport the available oxygen around the body.
    • the decreased oxygen is detected by the kidneys and they secrete erythropoietin
  3. Erythropoietin (EPO)
    • a hormone to increase the rate of erythropoiesis.
    • EPO increases the development of red cells in the bone marrow.
  4. RBC maturation
    • Nucleus is lost
    • Hemoglobin increases
    • Decreased cellular size
  5. True or False
    Early red blood cells are large, they have a nucleus, very little cytoplasm, and they lac hemoglobin.

    As a red blood cell matures, it becomes smaller, increases its hemoglobin content, and loses its nucleus.

    The loss of the nucleus results in the RBC gaining its biconcave shape

    it isn't mature yet; it still contains some mitochondria, ribosomes and sum ER .These are called reticulocytes
  6. Reticulocytes
    • An almost mature red blood cell
    • Theses are released into the bloodstream and will mature over the next 1-2 days.
    • Normally 0.5-1.5% of circulating RBCs are reticulocytes.
  7. Hematocrit (Hct)
    • this measures the relative amount of RBCs in the blood
    • it is the % of a patients whole blood that is occupied by red blood cells 
    • This averages about 45%, a little higher in men and a little lower in women.
  8. Polycythemia
    • the presence of too many red blood cells
    • increases the blood viscosity
    • it can manifest as a primary or secondary disease.
    • Primary polycythemia
    • Secondary polycythemia
  9. Primary polycythemia
    • Also known as polycythemia vera (PV)
    • An abnormality of the bone marrow causing and over production of RBCs
    • it may also result in an increase of WBCs and platelets 
    • The main problem is that it increases the viscosity of the blood, making the heart work harder and increase the likelihood of clotting.
  10. Secondary polycythemia
    • And increase in RBC numbers due to another condition.
    • Andy stimulus that causes hypoxemia can cause the bone marrow to increase the production of RBCs
    • Examples: smoking, sleep apnea, prolonged exposure to low atmospheric oxygen, dehydration, or heart disease.
  11. Erythropoiesis Imbalances
    • Anemia
    •   - a decrease in the normal number of RBCs
    •   -classified based on RBC size and hemoglobin content
    •      -Macrocytic, normocytic, and microcytic
    •      -Hypochromic and normochromic
    •   -Classified based on etiology
    •      -Iron deficiency, red cell destruction, autoimmune disease, hemorrhage, lack of production in the bone marrow.
  12. Types of Anemias 
    Low Hgb, Hct, and RBCs due to:
    • Hemorrhage anemia
    •   - due to bleeding

    • Hemolytic anemia
    •   -due to RBC lysis (descruction)

    • Aplastic anemia
    •   -lack of cell production in the bone marrow

    • Pernicious anemia
    •   -lack of vit. B12 absorption in GI tract

    • Iron deficiency anemia
    •   -lack of iron
  13. Leukocyte /Wight blood cells (WBCs)
    • are very different from RBCs
    • Larger then RBCs
    • Presence of nuclei
    • Lack of hemoglobin
    • there are two different kinds
    •   -Granulocytes and Agranulocytes
    •      -Apperance of granules
    •      -Staining characteristics
  14. True or false
    There are more WBCs circulating in the bloodstream then RBCs.

    There are fewer WBCs then RBCs.
  15. Granulocytic  Group
    • presence of cytoplasmic granules 
    • includes three specific WBCs (neutrophils, eosinophils, and basophils).
    • The names of these cells come from there staining characteristics
  16. Agranulocytes
    • contain some cytoplasmic granules but they are much less prominent and they don't stain as well as granulocytes.
    • Lymphocytes and monocytes are included in this group.
  17. Leukocytosis
    • an increase in the number of WBCs
    • within limits a normal physiologic response to diseases and conditions altering homeostasis
    •   -Pneumonia, appendicitis, abscess, leukemias, etc.
    • An increase in WBC numbers above 40,000 WBCs/mm3 is never a normal response.
  18. Leukemia
    • a cancer of the blood-forming cells, most often the WBCs
    • Levels above 40,000 would indicate an abnormal proliferation of white blood cells
  19. Leukopenia
    • a decrease in WBC numbers 
    • it is never a normal response
    • Causes can include: AIDS, chemotherapy, or bone marrow failure (aplastic anemia)
  20. When a patient has an increased _____ blood cell count a physician will frequently order a differential analysis.

    The physician wants to know the percentage of each of each type of white cell in the blood 

    This provides info relating to the patients condition
  21. Granulocytes:
    • Powerful phagocytes
    • Granular cytoplasm
    • Prominent in acute inflammation and bacterial infections
    • 60-70% of circulating WBCs
  22. Granulocytes:
    • Large red granules
    • Prominent in allergic responses and parasitic infections
    • 2-4% of circulating WBCs
  23. Granulocytes:
    • Large dark blue granules
    • Chronic inflammatory response
    • 0-1% of circulating WBCs
  24. Lymphocytes
    • Participate in specific cellular immunity
    • Major role in viral infections and cancer prevention
    • 20-25% of circulating WBCs
  25. Monocytes
    • Chronic inflammation and infection
    • 3-8% of circulating WBCs
    • Enlarge and mature into macrophages in various tissues of the body
  26. Platelets (Thrombocytes)
    • are cytoplasmic fragments of large cells in the bone marrow called megakaryocytes.
    • These are too large to leave the bone marrow and show up in the bloodstream (An individual megakaryocyte can release 2000-5000 platelets.)
    • platelets have a very short life span (5-9 days)
    • They help limit blood loss by forming a platelet plug, and releasing chemicals to encourage vasoconstriction and activate the clotting process.
  27. Hemostasis
    The overall process by which bleeding is stopped
  28. What are the three mechanisms involved in hemostasis?
    • Vascular spasm
    • Platelet plug formation
    • Coagulation (clotting)
  29. Vascular spasm
    • Smooth muscle contraction, reduces blood loss
    • Activated by chemicals from platelets, damage to smooth muscle and pain receptor reflexes.
  30. What are the three steps in which platelets form a plug?
    • 1. the platelets adhere to the wall of the blood vessel.
    • 2.  The platelets release their chemical contents.  This encourages further vasoconstriction and recruitment of other platelets.
    • 3.  The clumping of platelets is called platelet aggregation. with the activation of enough platelets, a loose platelet pug is formed.
  31. Coagulatoin
    taking that which is liquid (plasma) and make it a solid (clot)or at least a semi-solid.
Card Set:
Biomed Mod.15 obj.7-13
2013-02-21 05:22:09
Biomed Mod 15 obj 13

Biomed Mod.15 obj.7-13
Show Answers: