Hemocytoblasts membrane receptor cells respond to specific hormones or growth factors that push a cell towards this.
This begins when a hemocytoblast descendant called a myeloid stem cell is transformed into a proerythroblast.
The process of erythropoiesis, from hemocytoblast to reticulocyte takes how many days?
Process of erythropoiesis:
Hemocytoblast (stem cell)
Proerythroblast (committed cell)
Phase 1 of development? (early erythroblast)
Phase 2? (late erythroblast/normoblast)
Phase 3? (normoblast/reticulocyte)
Phase 1: ribosome synthesis
Phase 2: hemoglobin accumulation
Phase 3: ejection of nucleus
Hormones and levels of iron, amino acids, and certain B vitamins can affect this.
This glycoprotein hormone is produced by the kidneys (and small amount by liver)and circulates in blood at all times and sustains RBC production at a basal rate.
4 triggers for EPO formation
drop in O2 levels
reduced RBC due to hemorrhage or excessive destruction
insufficient hemoglobin per RBC (iron deficiency)
reduced availability of O2 (high altitudes, pneumonia)
Controls the absorption of iron from diet in response to changing body stores.
Appx. 65% of the body's iron supply is in this. Iron is also found in the liver, spleen, and bone marrow.
Iron is stored inside cells as protein-iron complexes such as these two.
Transport protein that loosely binds to iron in the blood. Erythrocytes take up the iron to form hemoglobin.
RBC disorder in which blood has a low oxygen-carrying capacity.
Three common causes of anemia.
insufficient number of RBCs (hemorrhagic, hemolytic, aplastic)
low hemoglobin content (nutritional)
abnormal hemoglobin (genetic)
Anemia typically in mediterranean people. A globin chain is absent or faulty, RBC are thin, delicate, hemoglobin deficient.
Abnormal hemoglobin that result in one change of the 287 amino acids in a beta chain of a globin. Low O2 = stiff rods form making hemoglobin spiky and sharp. RBCs become crescents.
Abnormal excess of RBCs. Increases blood viscosity. Severe cases are treated with blood dilution (removing blood, replacing with saline)
Type of polycythemia. A bone marrow cancer. Causes dizziness, hematocrit up to 80%, may double blood volume, and high RBC count (8-11 million)
Type of polycythemia. Less available O2 or increased EPO production. High altitudes, a normal physiological respose, RBC count of 6-8 million.
The only formed elements that are complete cells. Crucial to defense against disease. Move by amoeboid motion. Destroy foreign substances or dead cells (endocytosis).
WBCs slipping out of the capillary blood vessels for inflammatory or immune responses is called...
WBCs following the trail left by damaged or infected cells.
The production of WBCs.
These are larger, spherical, short-lived leukocytes with lobed nuclei, granules, and are phagocytes.
50-70% of WBCs. Neutral-loving granulocyte. Granules contain enzymes and defensins. 3 to 6 lobes. Kills by respiratory burst (releases bleach, hydrogen peroxide, defensin). Numbers increase during bacterial infections.
2-4% of WBC. Dark red nucleus with 2 lobes. Granules contain unique digestive enzymes. Attack parasitic worms. Lessen severity of allergies.
Rarest WBC, up to 1%. Granules contain histamine. U or S shaped nucleus. Base loving.
Two types of agranulocytes (lack granules).
Agranulocyte that is 25% or more of WBCs. LARGE dark purple nucleus. Rest in lymphoid tissues (lymph nodes, spleen, etc). T cells (vs. virus-infected and tumor cells) and B cells (give rise to plasma cells to produce antibodies).
3-8% of WBC. Largest leukocytes. U or kidney shaped nucleus. Enter the tissues to form highly mobile macrophages. Macrophages activate lymphocytes to mount the immune response.
Overproduction of abnormal leukocytes occurs in these two disorders.
Disorder - underproduction of abnormal leukocytes. Abnormally low WBC count. Induced by drugs (glucocorticoids, anticancer agents)
Disorders involving cancerous conditions involving WBCs. Bone marrow is totally occupied by cancerous leukocytes and immature WBCs flood into bloodstream. WBCs are nonfunctional. Death by internal hemorrhage and serious infections.
Two types of leukemias:
Leukocyte disorder caused by the Epstein-Barr virus. Excessive numbers of atypical agranulocytes. Highly contagious viral disease, seen in young adults. Low fever, chronic sore throat, tiredness, achiness.
Are cytoplasmic fragments of large cells, megakaryocytes. Purple staining granules contain chemicals for clotting (serotonin, Ca, enzymes, ADP, and PDGF). Anucleate, degenerate in 10 days if not involved in clotting.
Platelets circulate freely and are kept mobile but inactive by molecules (nitric oxide, prostacyclin) secreted by these type of cells lining the blood vessels.