Lab 2 Flashcards
What is blood made up of?
plasma: fluid matrix in formed elements (blood cells) are suspended in
90% water which nutrients, gases, hormones, metabolites, protein and minerals are dissolved or suspended
formed elements: erythrocytes or RBC = gas transport, leukocytes or WBC = immune system, thrombocytes or platelets = hemostasis or coagulation
What is the sedimentation rate?
rate at which erythrocytes sink to the bottom of test tube = calculated at mm/hr and is a non specific test
varies between species and affected by agglutination of RBCs and plasma proteins
affected by presence of disease in individual
increased rate in general infections, malignancy, arthritis, anemia and pregnancy (since less RBCs so can coagulate faster)
What a general clotting mechanism overview?
complex series of reactions that convert soluble plasma protein fibrinogen to insoluble protein fibrin
strands of fibrin form dense network where RBCs are trapped
clot: serves as a plug in injured blood vessels until damaged tissue is repaired and clot is broken down by enzyme plasmin
How can coagulation be prevented and why?
since coagulation requires calcium ions, adding substances that binds calcium ions prevent coagulation.
eg. EDTA = adding calcium chloride replaces the EDTA effects
What is hematocrit?
concentration of RBCs = can determine if dehydrate or anemic
indirect method: centrifuging blood sample to separate cells and plasma => packed cell volume (PVC) as a percentage of total volume
What is the permeability of RBC membranes in terms of water and ions?
water: permeable
ions: relatively impermeable like Na Cl
What happens if cells are bathed in salt solution that have a higher osmotic pressure due to higher concentration of solutes than that of cytoplasm?
water moves out of cells into the salt solution with the gradient
What are solutions which are lower in solute concentration than cytoplasm called?
hypotonic
What is hyper tonic?
solutions which are more concentrated than cytoplasm
What is isotonic?
solutions with the same concentration as cells
What are the primary functions of WBCs?
neutrophils: phagocytosis - important during inflammation
eosinophils: break down blood clots and kill parasites
basophils: synthesize and store histamine (inflammatory) and heparin (anticoagulant)
monocytes: phagocytosis like macrophages in tissues
lymphocytes: immune response (including production of antibodies)
Where are leukocytes produced?
bone marrow and lymph tissue
How can we do a differential WBC count?
stained blood smear by counting 100 cells and classifying them according to type - results recorded as a percentage of total WBC population
What are the percentages of each WBC?
neutrophils: 62%
lymphocytes: 30%
monocytes: 5.3%
eosinophils: 2.4%
How can you distinguish a neutrophil from a lymphocyte?
agranulocyte: lymphocytes and monocytes vs. granulocytes: eosinophils, basophils, neutrophils
