Assume that a 13 year old is studying blood in school, but has questions that haven’t been answered in class. These are some of the questions he asked you. Write a paragraph to answer his questions in language that will be understandable by a young teenager.
1. What is the significance of a lower than normal hematocrit? What is the effect of a bacterial infection on the hematocrit?
A significant drop in the hematocrit indicates anemia, a lower than normal number of red blood cells (RBCs). Lower values in women during their reproductive years also may be due to excessive loss of blood during menstruation.
A bacterial infection would increases the production the number of White Blood Cells (WBC), because the WBC are fighting off the infection may affect the hematocrit by lowering it.
2. Compare the development of lymphocytes with the development of the other formed elements?
Lymphocytes: produced in red bone marrow but lymphocytes can also be produced in lymphatic organs such as lymph nodes and spleen. Develop from lymphoid stem cells. B cells: Attack bacteria, viruses and toxins T cells: Acting directly against virus-infected cells and tumor cells Leucocytes: Only formed elements that are complete cells with a nucleus and usual organelles Develop from myeloid stem cells. Platelets: hemopoietic stem cells also differentiate into cells that produce platelets, under the influence of the hormone thrombopoietin, myeloid cells develop into precursor cells called megakaryoblasts that transform into megakaryocytes in the red bone marrow.
3. What is erythropoiesis? Which factors speed up and slow down erythropoiesis?
Erythropoiesis is the process of red blood cell formation or production which begins in the red bone marrow with a precursor cell called proerythroblast. It then divides several times until, producing cells that