blood cells lecture 1 Flashcards
(31 cards)
where are blood cells produced?
blood cells are produced in the haemopoietic tissue in the bone marrow.
what is haemopoitic tissue?
tissue which can give rise to any type of blood cell.
after centrifugation of a blood sample, what i the white ‘buffy coat’ composed of?
white blood cells and platelets
what are erythrocytes?
Red blood cells
what is the average lifespan of RBCS?
120 days
what is the name of newly formed erythrocytes?
reticulocytes
how long does it take for reticulocytes to mature into erythrocytes?
24 hours
how can reticulocytes be distinguished from erythrocytes in histology?
reticulocytes still contain some RNA in their cytoplasm which can be stained with CRESYL VIOLET and METHYLENE BLUE
what percentage of a normal blood sample would be composed of reticulocytes?
between 0.5 and 1%
graph of treatment of patient with B12 deficiency what are the key features of this graph?
the reticulocyte peak is early and rapid; slow recovery of RBCs level and Haemoglobin level to normal
what type of cells make up the granulocytes?
neutrophils, eosinophils and basophils
what are leucocytes?
white blood cells (granulocytes, monocytes and lymphocytes)
what is a differential cell count?
the proportions of different leucocytes in a blood sample
what are the physical features of a neutrophil?
segmented, multi lobed nucleus, most abundant leucocyte
what are the physical features of a eosinophil?
segmented nucleus, granulated cytoplasm
what are the features of a basophil?
very dense appearance, very rare, very granulated
what are the features of a monocyte?
bigger than other leucocytes, larger nucleus. Called macrophages when they migrate to other tissues. Have different names in different tissue types.
what are the features of lymphocytes?
mainly nucleus, little cytoplasm, no granules.
what are the functional properties of neutrophils?
neutrophils are the first line of defence of invading pathogens: they are highly phagocytic and are able to engulf very large cells. they have a very important role in the inflammatory response.
what are the functional properties of eosinophils?
contain many and several different types of granules which contain active agents to kill other cells. Involved in the destruction of parasites in the gut.
what are the functional properties of basophils?
Basophils are also full of granules. Secrete heparin to prevent clotting. Also involved in allergic reactions by the release of agents from the granules. Involved in athsma.
what is the lgE antibody?
an antibody that binds to receptors on the surface of mast cells or basophils, involved in allergic reactions. allergens bind to this antibody.
what are the most important chemical agents released form mast cells or basophils in an allergic reaction?
histamine, ECF-A (eosinophil chemotactic factor of anaphylaxis) and SRS-A (slow reactive substance of anaphylaxis)
what are the functional properties of monocytes?
migrate in the blood to different fixed tissues where they become macrophages. Involved in phagocytosis: clearing away necrotic tissue and dead cells.
