Peripheral Blood Flashcards
What kind of tissue is blood?
Specialized connective tissue
What is the approximate volume of blood in the average person?
5-6 L
What are the main functions of blood?
Transport of oxygen, nutrients, hormones, etc.; transports of waste products away from tissues; maintenance of homeostasis; immune activity
What are the layers that result from blood centrifugation?
Plasma, buffy coat, and erthyrocytes
What are the major components of the plasma?
Mostly water, albumin, globulins, fibrinogen, electrolytes
What is the function of albumin in the plasma?
Maintenance of colloid osmotic pressure in vessels and acts as a transport protein
What is the major difference between serum and plasma?
In plasma, the blood is mixed with anticoagulants and so clotting factors are present in the plasma. No anticoagulants are used with serum and so blood is allowed to clot and, therefore, serum is devoid of most clotting factors
What are the formed elements of the blood?
RBCs, WBCs, and platelets
What is the typical lifespan of a red blood cell?
120 days
How are senescent RBCs removed from circulation?
Macrophages of the spleen, liver, or bone marrow
What is the shape of the typical, healthy red blood cell? What causes this shape? What is the physiologic advantage of this?
Biconcave discs due to lack of nuclei and organelles; this increases their surface area, which is beneficial for gas exchange and allows the RBCs to deform themselves to pass through very small capillaries
What specialized feature is found on the inner surface of the RBC? What is the most abundant cytoskeletal protein in this feature? What proteins anchor this feature to the membrane?
A filamentous network of proteins; Spectrin; Ankyrin, band 3, glycophorin C, and protein 4.1
What are spherocytes?
Small, sphere-shaped red blood cells that are more fragile than normal RBCs
What are elliptocytes?
RBCs that are elliptical in shape that may be more fragile
What chains compose fetal Hb? Hb A1? Hb A2?
2 alpha and 2 gamma; 2 alpha and 2 beta; 2 alpha and 2 delta
What mutation results in Hb S?
Single substitution of valine for glutamic acid in the beta chain
What are symptoms of sickle cell disease crisis?
Fatigue, anemia, pain from ischemia and infarction, microvascular blockages affecting organs of the body
What causes the development of spherocytes and elliptocytes?
Defects in cytoskeletal proteins of the RBC
What is hematocrit?
the % of whole blood volume that is made up of RBCs
What is anemia? What can cause it?
A condition in which there is decreased RBCs or hemoglobin in the blood; may be due to blood loss, decreased RBC production or increased RBC destruction
What are the 4 RBC indices?
Mean corpuscular volume; mean corpuscular hemoglobin; mean corpuscular hemoglobin concentration; and red cell distribution width
What is the term used to described mean corpuscular volumes above normal? Below normal?
Macrocytic and microcytic
What terms are used to describe high and low hemoglobin content (MCH and MCHC)?
Hyperchromic or hypochromic
On what criteria are anemias classified?
According to the cause and according to the RBC size and Hb concentration
What is aniscytosis? Poikilocytosis?
Variation in size of RBCs; variation in shapes of RBCs
What is polycythemia/ erthyrocytosis?
A condition with an elevated RBC count
What are the antigens of the ABO blood group system?
A and B antigens
What kind of blood does a person with both A and B antibodies have?
Type O
What is a transfusion reaction? What symptoms are associated with one?
When a patient receives incompatible blood and their antibodies attack the RBCs; allergic, febrile, and hemolytic
Besides the ABO group, what is the other clinically significant blood group system? What antigen is associated with Rh + blood?
Rh group; D antigen
What is erythroblastosis fetalis?
Occurs when an Rh negative mother becomes pregnant with their second Rh + child and has developed antibodies that attack the child
What are the subclassifications of leukocytes? What are these classifications based on?
Granulocytes or agranulocytes; based on the presence of specific granules in the cytoplasm
What leukocytes contain nonspecific azurophilic granules?
All of them
Which leukocytes are granulocytes? agranulocytes?
Neutrophils, Eosinophils and Basophils are granulocytes; lymphocytes and monocytes are agranulocytes
What are nonspecific (azurophilic, primary) granules?
Lysosomes present in all leukocytes containing proteases and antibacterial proteins
What are specific granules?
Granules specific to the function of neutrophils, eosinophils and basophils
What additional information does a CBC with differential contain?
Percentages of the different types of WBC’s in the blood
What is leukocytosis? How is it classified? In what conditions is it seen?
An increase in WBC count- usually classified according to cell type increased (e.g., neutrophilia, eosinophilia); Seen in infections, allergic reactions, malignancies
What term describes a decrease in WBC count? What leukocyte is most commonly reduced? What can cause this?
Leukopenia; Neutrophils; Chemotherapy, radiation therapy, steroids, malignancies
How are lymphocytes classified?
Classified as small, medium, or large with relation to the size of RBCs
A viral infection would mostly cause elevation of what kind of leukocyte?
Lymphocytes
What are the different lymphocytes?
Include B,T, and NK cells
What is the size of the nucleus of the lymphocyte relative to the size of the cell?
The nucleus nearly fills the cell
What are the largest white blood cells?
Monocytes
What cell serves as the precursor for macrophages, osteoclasts, and other cells of the mononuclear phagocyte cystem?
Monocytes
At what point do monocytes become macrophages?
When they migrate into tissues
What are the functions of monocytes?
Function in phagocytosis and antigen presentation as well as secretion of inflammatory cytokines
What is the most numerous white blood cell?
Neutrophils
In which leukocytes are Barr bodies visable?
Neutrophils
What granules do neutrophils contain? What does each contain/what is each used for?
Azurophilic- contain myeloperoxidase and defensins which function in killing bacteria; secondary- contain lysozyme, lactoferrin, and collagenase which function to kill and degrade microbes; and teritiary- adhesion molecules and metalloproteinases such as gelatinase which assist in migration
What is diapedesis?
The migration of WBC out of vasculature and into tissues
What are the “first responders” of the immune system?
Neutrophils
What is the typical morphology of an eosinophil nucleus?
Usually bilobed
What are the functions of eosinophils?
Defense against parasitic infections, modulatory role in allergic and inflammatory reactions
Why are eosiniphilic granules distinctive on electron microscopy?
They have crystalline cores containing major basic proteins
What are the functions of basophils?
Release histamine, heparin, and other mediators in allergic reactions, modulate inflammation, and play a role in type 1 hypersensitivity
What are platelets? From what cell type are they derived?
Small, non-nucleated fragments of cytoplasm released from megakaryocytes
What is the primary function of platelets?
Coagulation
What is the outer, light-staining portion of platelets? The inner dark staining portion?
Hyalomere and granulomere
What structures are included in the hyalomere of platelets?
Marginal band, dense tubular system, open canalicular system
What granules are contained in platelets? What are the functions/contents of each?
Alpha granules (proteins related to adhesion, clotting and repair) and dense granules (ADP, ATP, serotonin, and histamine for adhesion and vasoconstriction)
What is thrombocytopenia? Thrombocytosis? What are the possible consequences of each?
Low platelet count- easy bruising, prolonged bleeding; excessive platelet count- stroke or heart attack
