BMTCN Review 2023/2024 updated to pass

BMTCN ReviewWhy are cell renewal mechanisms important? - correct answer Because of senescence, utilization, and emigration What is the objective of hematopoiesis? - correct answer Maintain peripheral blood with a constant level of different types of blood cells What is immune function partially dependent on? - correct answer Hematopoiesis Define innate immunity: - correct answer These responses occur naturallyand utilize phagocytic cells that release inflammatory mediators as well as nature killer (NK) cells. Define acquired immunity: - correct answer The responses involve antigen specific B and T cells and are either humoral or cell mediated. When do problems arise in the immune system? - correct answer Problems arise when there is overwhelming infection, inherited genetic mutations, acquired disorders, aging, and medications that interfere with normal immune function Red Bone Marrow - correct answer Consists of HSCs and originates in flat and long bones. At birth, BM is red and converts to yellow as one ages. Yellow Bone Marrow - correct answer Consists of fat cells and resides in the hollow interior of the middle portion of long bones. At birth, BM is red and converts to yellow as one ages. BM during fetal development: - correct answer Hematopoiesis occurs in the liver and yolk sac. 20th week of gestation, BM begins to produce blood cells, and by week 30, BM has achieve normal cellularity. 90% at birth. BM during childhood: - correct answer Hematopoiesis occurs in the long bones. BM at age 30: - correct answer Hematopoiesis occurs exclusively in the axial skeleton, pelvis, vertebrae, ribs, sternum, and skull. Cellularity is at 50% BM at age 70: - correct answer Declines to 30% cellularity Define extramedullary hematopoiesis: - correct answer If BM injury occurs, hematopoiesis can resume in the liver and spleen What plays a critical role in the immune system by developing and training T cells for adaptive immune function? - correct answer Thymus When is the thymus most active? - correct answer From birth through puberty What happens to the thymus during puberty? - correct answer Anatomically reduces in size and is replaced with fatty tissue; this results in a decline in hematopoietic tissue as well as adaptive immunity In healthy individuals, what is the circulation of HSCs? - correct answer Peripherally 0.06% and BM is 1.1% Why do HSCs spend a majority of their time outside of the cell cycle? - correct answer Quiescent; they are activated for the purpose of homeostasis or tissue repair How often do HSCs regenerate? - correct answer Every two to three months Why can progenitor cells not renew? - correct answer They always commit to one specific cell differentiation pathways that lead to the production of specific blood cells What two pools do HSCs belong to? - correct answer One that is dormant and proliferates every few months while maintaining self-renewal potential. The other is activated and proliferates every thirty days. This pool does not have self-renewal abilities