Hematopoiesis Flashcards
What is a poikilocyte?
An erythrocyte with an abnormal shape (i.e. sickle cell, ect.)
What is pyknosis?
The process of nuclear shrinkage observed in erythropoiesis. Results in a dense nucleus which is extruded from cell.
What are the erythrocyte progenitors?
proerythroblast, basophilic erythroblast, polychromatophilic erythroblast, orthochromatophilic erythroblast, polychromatophilic erythrocyte (reticulocyte), erythrocyte (mature RBC).
What causes basophilic staining in some erythrocyte progenitors?
The presence of large amounts of RNA.
What causes polychromatophilic staining in some erythrocyte progenitors?
The presence of RNA as well as hemoglobin.
What are the characteristics of proerythroblasts?
Large (12-15 μm) cells with a large, round nucleus. Are mildly basophilic.
What are the characteristics of basophilic erythroblasts?
Are smaller than proerythroblasts and possess a smaller, more dense nucleus. Have a very basophilic cytoplasm.
What are the characteristics of polychromatophilic erythroblasts?
They are the last cells capable of mitosis, and their nuclear membrane is course and easily seen. Hemoglobin production begins which results in a grey/lilac cytoplasm. Are smaller than basophilic erythroblasts.
What are the characteristics of orthochromatophilic erythroblasts?
Possesses a small, deeply stained nucleus (ready to be extruded). Begins to acquire acidophilia but is still retains slight basophilia.
What are the characteristics of polychromatophilic erythrocytes? (i.e. reticulocytes)
The nucleus has been extruded. Has an acidophilic cytoplasm with traces of the earlier gray (RNA remnants).
What are the characteristics of erythrocytes?
They are 7.5 μm in diameter and possess a biconcave disk shape. Have an acidophilic cytoplasm.
What are the progenitors of thrombopoiesis?
megakaryoblast, promegakaryocyte, and mature megakaryocvte
What are the progenitors of granulocytopoiesis?
Myeloblast, promyelocyte, myelocyte, metamyelocyte,, stab cell, and mature granulocyte. The myelocyte stages and onward have specific versions based on what granulocyte they will become (neutrophil, eosinophil, basophil).
What are the largest leukocytes in the blood?
Monocytes (12-20 μm in diameter)
What transcription factors does monocyte maturation require?
PU.1 and Egr-1
