Lab 2- Blood Flashcards
Functions of Blood
Transport system
– Oxygen (RBCs)
– Nutrients
– Hormones
– Carbon dioxide
– Waste products
-Regulates body pH, and ion concentration
(e.g. Ca+ and K+)
-Protects against fluid (blood) loss by
repairing blood vessels and clotting
(platelets)
Protects against disease (WBCs)
‒ Phagocytosis (nonspecific immunity)
‒ Produces antibodies (specific immunity)
Regulates body temperature
Composition of Whole Blood
Adult males: 5 – 6L
Adult females: 4 – 5L
—Fluid connective
tissue:
Plasma = nonliving fluid(extracellular) matrix
Formed elements = living
cells and fragments suspended in the matrix
—When a clot forms you can
see the fibrin threads, which are the fiber component of the matrix
RBC’s
-contain hemoglobin
-transport oxygen and some carbon dioxide
-most numerous blood cell type
-no nucleus
-no repair or reproduction
-produced in red bone marrow
-biconcave disk (stack and squeeze through capillarues)
-
Platelets
-Small (2-4μm), irregular shaped, cell fragments from large cells in bone
marrow called megakaryocytes
-Form a platelet plug and
promote clotting when
blood vessels are damaged
-Stain dark
-Normal clotting time = 2 to 6
minutes
-150,000 – 400,000/mm
Leukocytes – White Blood Cells (WBCs)
-5 types
-immune system function (non specific and specific
-nucleated
-agranulocytes and granulocytes
agranulocytes
-no visible granules
-more numerous in the tissues than in the blood
granulocytes
-conspicous granules
neutrophil
– Dark multilobed nucleus with
strands
lymphocyte
– Relatively small
– Dark nucleus fills cell, rimmed by
light cytoplasm
monocyte
– Large
– Dark kidney-shaped nucleus
eosinophil
– 2-lobed nucleus with a strand
connecting
– Pink granules
basophil
– Nucleus obscured by dark purple
granules
White Blood Cells
Identifying characteristics
- Relative abundance and
size
‒ Nucleus shape
‒ Colour when stained
‒ Shape of granules
‒ Amount of cytoplasm
leukemia
- Excessive number of one type of leukocytes due to mutation and loss of growth control
- Cells are often also immature – blast type cells
- 4 types: chronic vs acute; lymphocytic vs myeloid
– CLL; CML
– ALL: AML
Agglutination
-Antibodies in plasma (proteins) develop according to blood type after birth
-Antibodies react with antigens on RBCs of foreign blood
-Antibodies bind to opposing antigens and cause agglutination (clumping) - occurs if a person is given mismatched blood during a transfusion
Rhesis (Rh) Factor
-85% of North America population
-no pre formed antibodies in plasma of Rh but can form antibodies if exposed
-transfusion reaction occurs if second exposure of Rh- person to Rh+ blood (important during pregnancy)
m
Hematocrit (Hct)
– Percentage of total blood volume
occupied by RBCs
Same as Packed cell volume (PCV)
– Normal in men: 45 to 52%
– Normal in women: 37 to 48%
– Relative measure of RBC count -
should remain steady
– Affected by hydration status
– Collect blood in a capillary tube,
centrifuge to separate RBCs and
WBCs from plasma - Demo
Anemia
– Hematocrit (RBC count) or hemoglobin abnormally low
– Decrease in oxygen-carrying capacity due to a decrease in the total
number or size of RBCs in the blood or a decrease in the quality or
quantity of Hb.
– Many types but the mechanisms causing anemia can be classified
as follows:
‒ Impaired RBC production
‒ Blood loss
‒ Increased RBC destruction
‒ Iron deficiency
‒ Vitamin B12 or folic acid deficiency
Polycythemia
– Hematocrit abnormally high (> 65%)
– Increased blood viscosity (HBP, stroke)
– Any condition causing dehydration (relative increase of RBCs) or
increased number of RBCs produced
e.g. bone marrow disorders such as cancer, high altitude exposure, doping
Leukopenia
– A decrease in the number of WBCs
– Occurrence due to prolonged stress, severe
infections, bone marrow depression
Leukocytosis
– An abnormally high number of WBCs
– Occurrence due to inflammation, allergies,
acute (early stage) infections
