MLS Hematology Questions with Correct Solutions Graded A+

Hematopoiesis - Production and development of blood cells normally occurring in the bone marrow Yolk sac - -the beginning of hematopoiesis -begins as early as the eighteenth day after fertilization Aorta-gonad-mesonephros (AGM) - -the beginning of intraembryonic hematopoiesis -beings at about four weeks of gestation Where is the location of hematopoiesis during the fetal development at the third month? - liver Bone Marrow - -the blood-forming tissue located between the trabeculae of spongy bone -location for formation and maturation of blood cells Two major departments of the bone marrow - -vascular compartment -endosteal compartment Vascular Compartment - composed of the bone marrow arteries and veins, stromal cells, and hematopoietic cells Endosteal Compartment - the primary site of bone remodeling but also contains hematopoietic stem cells (HSCs) Bone Marrow Hyperplasia - -an excessive proliferation of normal cells -occurs with all conditions of increased of ineffective hematopoiesis Extramedullary hematopoiesis - the formation and development of blood cells at a site other than the bone marrow Bone marrow is the site of cell development for ____________. - -myeloid cells -erythroid cells -megakaryocytic cells (mother cells) -lymphoid cells What are other sites of cell development for lymphoid cells besides the bone marrow? - -thymus -spleen -lymph nodes Bone Marrow Hypoplasia - -hematopoietic tissue becomes inactive -fat cells increase to offer a cushion for the marrow What are some causes for bone marrow hypoplasia? - Environmental factors -chemicals -toxins Genetically determined Blood Cell Passage - blood cells migrate from bone marrow to the vascular space What causes extramedullary hematopoiesis? - hyperplasia of the marrow does not meet the physiologic needs of the tissues Where does extramedullary hematopoiesis usually occur? - -liver -spleen Thymus - lymphopoietic organ -bilobular organ with an outer cortex and central medulla -supplies immunocompetent T lymphocytes to T-dependent areas What is inside the cortex of the thymus? - -small lymphocytes (thymocytes) -cortical epithelial cells -few macrophages What is inside the medulla of the thymus? - -mature thymocytes -medullary epithelial cells -dendritic cells -macrophages Hypersplenism - spleen may become enlarged -happens through the exaggeration of its normal activities of filtering and phagocytosis What does hypersplenism cause? - -anemia -leukopenia (decreased WBC) -thrombocytopenia (decreased platelets) -combinations of cytopenias (decreased cells) Splenectomy - removal of the spleen Splenectomy's effect of the lifespan of RBCs - stays the same Kupffer cells - -special macrophages that line the sinusoids -performs similar filtering functions as the phagocytes in the splenic cords and marginal zones What does acquired hyposplenism represent? - a complication in sickle cell anemia What does the lymphatic system consists of? - -lymph nodes -lymphatic vessels What is lymph formed from? - -blood fluid that escapes into connective tissues Lymphatic vessels - -carry lymph toward the ducts near the neck where lymph enters the blood -drains into the left and right lymphatic ducts Lymph nodes - -bean-shaped and occurs in groups or chains along the larger lymphatic vessels -contain an outer area called the cortex and an inner area called the medulla