Blood and Hematopoiesis Flashcards
Hematopoiesis
Process of blood cell development
Hematopoietic tissues
Fetus- liver is primary site, with some occurring in the thymus, spleen, and lymph nodes;
Infancy through adulthood- bone marrow is primary site; If marrow is compromised can make blood cells in liver, spleen and nodes again.
Formed element
RBCs, WBCs, platelets
Formed elements of blood
%
%RBCs (aka hematocrit): 3 times hemoglobin males=41-53 %; females=36-46% %WBCs: 1% %Plasma: 49-64%
Characteristics of plasma
liquid extracellular component. 90% water, 7% protein, .9% inorganic ions, remaining: nutrients, blood gases, hormones
Major plasma proteins
Albumin (increases osmotic pressure, protein carrier, most abundant),
Globulin (alpha/beta: protein carriers, clotting factors, lipoproteins. gamma: immunoglobulins)
Fibrinogen and Prothrombin (clot formation)
Serum
Clear yellow supernatant remaining after blood coagulates and centrifuge
Contains factors released from platelets and most of the components of plasma except: clotting factors, platelets, cells.
Erythrocytes
Red blood cell, bi-concave, non-nucleated, contains hemoglobin
Macrocyte
RBC > 9 micrometers diameter.
Low levels of B12 and folate interfere with DNA synthesis, cellular formation takes longer, but hemoglobin synthesis kept going.
Microcyte
RBC:
Reticulocyte
Immature RBC that has entered circulation.
1-2% of RBCs in circulation, still has some RNA which stains as blue aggregations
Concentration of RBCs in blood of adult male/female
Male:41-53%
Female: 36-46%
RBC life span and function
Lifespan: ~120 days
Function: transport O2 to tissues and carry CO2 away
Major classes and types of leukocytes, lifespan, and %
Granulocytes: Neutrophils- 50-70% of leukocytes in circulation; lifespan of 1-4 days Eosinophils- 1-3%; 6 days Basophils- less than 0.3%; 1-2 days Agranulocytes: Monocytes: 2-8 %; \_\_\_ days Lymphocytes: 18-42%; \_\_\_\_ days
Types of cells associated with each class of leukocyte and their function
Neutrophils: Formed in bone marrow, stored in medullary, live in CT before dying by apoptosis, phagocytize bacteria and small particles in tissue. First responders to inflammation & infection.
Eosinophils: epithelia tissue of bronchi, GI tract, uterus, and vagina. Down regulators in allergic reactions, produce histamine and arylsulfatase to break down histamine and leukotrienes released by other cells. Indicates helminth infection (peroxidases to kill worm)
Basophils: release heparin, histamine, peroxidase, leukotrienes, and eosinophilic chemotactic factor. Become mast cells when they enter CT. Elicit allergic symptoms
Lymphocyte: T cells, B cells, involved in humoral immunity and the precursors to plasma cells, which form antibodies. Natural killer cells (kill virus infected cells & some tumor cells
Monocyte: precursor for mononuclear phagocytotic system, when they enter CT, they become macrophages
Concentration of leukocytes/microliter blood
Neutrophils: 1800-7700/ microliter blood Eosinophils: 600/microliter blood Basophils: 200/microliter blood Lymphocyte: 1000-4800/microliter blood Monocyte: 900/microliter blood
Relationship between leukocytes and connective tissue
Neutrophils: Live in CT for 1-4 days before before apoptosis
Eosinophils:
Basophils: Become mast cells when they enter CT
Lymphocytes:
Monocytes: precursor cells for mononuclear phagocytotic system, and become macrophages when the enter CT
Compartments a neutrophil passes through during maturation
Formed in red bone marrow in medullary cavity, undergo mitosis in mitotic compartment (3 days), progress to maturations compartment (4 days) while they finish developing. Fully matured they are moved to medullary storage where they can be released in large numbers if needed.
Origin and role of band neutrophils
Immature granulocytes, indicate infection when elevated in the blood. Bands are in the development stage following a metamyelocyte and have a curved, elongated nucleus.
Function of Eosinophils
Surround parasitic worms (granules containing major basic protein, cationic protein, and peroxidase kills worms)
Down-regulate inflammation (histamines and arylsulfatase granules inactivate histamine and leukotrienes, phagocytose antigen-antibody complexes)
Conditions under which eosinophil numbers increase
Allergic reaction, helminthic/parasitic infection
Two major classes of lymphocytes and the ways in which they are distinguished
T cells: 60-80% of lymphocytes, originate in bone marrow, mature in thymus, DNA rearrangement confers antigen diversity, circulate among secondary lymphatic tissues, cell mediated immunity, helper T cells activate B cells
B cells: 20-30%, originate and mature in bone marrow, DNA rearrangement confers antigen diversity, circulate via lymph and blood, humoral (fluid based) immunity, activated by specific antigen AND helper T cell, precursor to plasma cells