MLS 301 Lecture Notes - Lecture 4: White Pulp, Yolk Sac, Lymphopoiesis
Document Summary
Objectives: upon completion of this lesson, the student will be able to: Cell production, maturation, destruction occurs in reiculeoendothelial system(res): function is hematopoiesis, phagocytosis, immune defense. Extramedullary hematopoiesis: blood cell production in hematopoietic tissue other than bone marrow. Liver and spleen can take over blood needs of tissues if bone marrow is affected due to hematologic disorders. Identify phases and site of origin for cellular development of active hematopoetic tissue. Explain the role of other organ systems in hematopoiesis. The yolk sac is the start of the embryo (18th day after) first blood vessels. Liver becomes the major site of blood(few months in) Hepatic phase: produces erythroid cells, myeloid and lymphoid cells. Spleen, kidney, thymus, lymph nodes and bone marrow is primary site of hematopoiesis: Medullary phase( 6th month of gestation and continues after birth) Explain the development of blood cells, including the sites of active hematopoiesis, through normal human development from the embryo to the newborn including the following:
