EXAM 3: HEMATOLOGY STUDY GUIDE (BASED ON EXAM REVIEW SLIDES)

EXAM 3: HEMATOLOGY STUDY GUIDE (BASED ON EXAM REVIEW SLIDES)Exam 3: Hematology Study Guide (Based on Exam Review Slides) Hematology: Erythropoiesis: Erythrocyte Differentiation • Erythropoiesis: formation of new RBCs only (subset of hematopoiesis) • Start w/ erythroid progenitor cell and then w/ erythropoietin (which is synthesized and released by the kidney), its an exocrine hormone, that then helps convert erythroid progenitor cell (stem cell) to a proerythroblast (committed progenitor cell) and then that morphs into a normoblast and then that morphs into a reticulocyte and then that differentiates into an erythrocyte so we’ve got several stages of development • Key points: 1. As the progression goes from left to right the cell becomes much more functional and effective ▪ For ex: the reticulocyte phase, the phase before the differentiation (maturation) into a true erythrocyte (mature cell), is far less effective. It’s not an adult, grown-up, fully functional RBC (like erythrocytes are). 2. The nucleus of the cell shrinks as it moves through this maturation pathway to the point where the reticulocyte no longer has a cell nucleus (it’s a baby cell, it’s still undergoing growth and development) so idk why the nucleus dissolves, but the ribosomes remain, so they are capable of generating globulin and heme (mitochondria are still in the reticulocytes so they are still able to generate Hemoglobin (Hgb)) so the development of Hgb continues even though there’s no nucleus w/in the reticulocyte (Hgb: iron-containing oxygen-transport metalloprotein in RBCS; in the blood it carries oxygen from the lungs to the rest