Functional grammar is a linguistic theory that states all constituents, whether affixes, words, phrases, or sentences, have semantic, syntactic, and pragmatic functions.Functional grammarians can classify linguistics as semantic, pragmatic, morphosyntactic, or phonological.he most famous of these is Systemic Functional Grammar, which was first published by British linguist Michael Halliday in 1961. Other functional grammars include Danish Functional Linguistics, lexical functional grammar, and Role and Reference Grammar.
hematopoiesis. the formation and development of blood cells, usually taking place in the bone marrow. cyclic hematopoiesis of collies. see canine cyclic hematopoiesis.[hÄâ²mÉtÅpÅÂ·Äâ²sis, hemâ²-]. Etymology: Gk, haima + poiein, to make. the normal formation and development of blood cells in the bone marrow. In severe anemia and other hematologic disorders, cells may be produced in organs outside the marrow (extramedullary hematopoiesis).xtramedullary hematopoiesis. the formation of and development of blood cells outside the bone marrow, as in the spleen, liver and lymph nodes. fetal hematopoiesis. in embryogenesis migration of stem cells from the yolk sac blood islands sets up hematopoiesis in thymus, lymph nodes, liver and spleen.
Medical Definition of Hematopoiesis Hematopoiesis: The production of all types of blood cells including formation, development, and differentiation of blood cells. Prenatally, hematopoiesis occurs in the yolk sack, then in the liver, and lastly in the bone marrow. In the normal situation, hematopoiesis in adults occurs in the bone marrow and lymphatic tissues. All types of blood cells are derived from primitive cells that are pluripotent (they have the potential to develop into all types of blood cells).