Proerythroblasts, lymphoblasts, myeloblasts, monoblasts, and megakaryoblasts share what precursor cell type?
Pluripotent hematopoietic stem cells
Reticulocytes are precursors for what type of blood cell?
Lymphoblasts are the precursors for what two blood cell types?
B cells and T cells
When B cells and T cells mature, what do they become, respectively?
B cells mature into plasma cells whereas T cells become activated T cells
Monocytes develop from what immediate precursor blood cell type?
What precursors indicate that a stem cell has differentiated into the platelet lineage?
Megakaryoblasts, which become megakaryocytes that form platelets
Neutrophils, eosinophils, and basophils differentiate from what common precursor blood cell type?
Promyelocytes, myelocytes, metamyelocytes, and stab cells are precursors for what three granulocytes?
Neutrophils, eosinophils, and basophils
In a normal blood sample, name the differential of white blood cells from most to least numerous.
Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils (remember: Neutrophils Like Making Everything Better)
What feature of the erythrocyte structure permits easy gas exchange of oxygen and carbon dioxide?
The biconcave disc shape permits a high surface area to volume ratio and facilitates gas exchange
What molecule do erythrocytes depend upon exclusively for energy?
Glucose; remember, they cannot use ketones for energy
What is the average lifespan of an erythrocyte in a normal human host?
Where does an erythrocyte obtain the adenosine triphosphate that it needs for energy?
Glucose: 90% is anaerobically degraded to lactate, whereas 10% goes to the hexose monophosphate shunt
What role does the erythrocyte play in acid/base physiology?
Erythrocytes carry carbon dioxide from the periphery to the lungs for elimination
How do erythrocytes facilitate transport of carbon dioxide away from the peripheral tissues?
The chloride-bicarbonate antiport produces a physiologic chloride shift, resulting in cellular loss of chloride and gain of bicarbonate (and thus carbon dioxide)
How would you describe a peripheral blood smear that shows an increased number of red blood cells and numerous immature red blood cells?
There is an erythrocytosis or polycythemia (increased number of cells) and a reticulocytosis (increased immature cells)
How would you describe a peripheral blood smear showing red blood cells of varying sizes and of varying shapes?
This smear exhibits anisocytosis (varying sizes) and poikilocytosis (varying shapes)
How do mature platelets form from large megakaryocyte precursors?
Small portions of cytoplasm fragment off of megakaryocytes
What is the role of platelets immediately following an injury such as a laceration?
Primary hemostasis; for example, they help prevent leakage of red blood cells from damaged vessels
What happens to platelets when they are in the presence of damaged endothelium?
Platelet activation; sticky platelets aggregate and interact with fibrinogen to form a hemostatic plug
What two types of granules do platelets contain?
Dense granules and alpha granules
What are the contents of the dense granules of platelets?
Adenosine diphosphate, calcium
What are the contents of the granules of platelets?
von Willebrand's factor, fibrinogen
Where in the body would you typically find the most platelets at any one time?
Approximately one third of the platelet pool is stored in the spleen
What is the life span of a platelet?
You note multiple small red lesions on the skin of a patient that do not blanche with pressure; what are two possible etiologies of these lesions?
These are petechiae, which can be caused by a low platelet count (thrombocytopenia) or dysfunctional platelets
Granulocytes and mononuclear cells are what kind of blood cells?
Leukocytes (leuk = white; cyte = cell)
Name three types of granulocytes.
Basophils, eosinophils, and neutrophils
Name two types of mononuclear cells.
Lymphocytes and monocytes
What is the main function of leukocytes?
To defend against infection