HEMATOLOGY
FUNCTIONS
FOUR MAIN FUNCTIONS:
• Transport oxygen, nutrients, cellular waste products
and hormones
• Nutrients from digestive tract to cells, waste products to
excretory organs, and hormones from secreting cells to
other parts of the body
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Aids in distribution of heat
Regulates acid-base balance
Helps protects against infection
BLOOD IS A VITAL FLUID TO OUR LIFE AND HEALTH
Read table 12-1 pg. 241
PLASMA
• Discussed in previous power point
• Liquid part of blood
• What makes up blood?
• What is the purpose of each substance?
• Plasma proteins
• Which are…
REMEMBER?
BLOOD PLASMA
• Straw-colored
• Comprising about 55% of the blood volume!
• Contains 6 substances:
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Water
Plasma proteins (all are formed in the liver)
Nutrients
Electrolytes
Hormones, vitamins, and enzymes
Metabolic waste products
AND…
PLASMA PROTEINS
• 3 proteins:
• Fibrinogen
• Necessary for blood clotting; without, a small cut or wound
would bleed profusely
• Serum albumin
• Most abundant of all the plasma proteins
• Helps to maintain the blood’s osmotic pressure and volume by
providing “pulse pressure” needed to hold and pull water from
the tissue fluid back into the vessels
• Serum globulin
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Also formed in the lymphatic system
Gamma globulin: helps in the making of antibodies
Prothrombin: helps blood coagulate
Vitamin K is necessary in aiding the process of prothrombin
synthesis
ERYTHROCYTES
• Also previously discussed
• Contains hemoglobin
• Transports O2 to tissues and CO2 away from cells
• Red cells travel to lungs to get O2 and give up CO2, then to
tissues to deliver O2 and pick up CO2
• Erythropoiesis
• Manufacture of red cells in bone marrow
• Hematopoiesis
• Formation of blood cells
• Occurs in what part of long bones?
• All blood cells develop from stem cells (hematocytoblasts)
• What was the life span of RBCs?
CONTINUED
• Oxyhemoglobin
• Formed when O2 combines with hemoglobin
• Carbaminohemoglobin
• Blood cells in the veins which are responsible for the dark,
reddish-blue color
• Hemolysis
• Rupture of erythrocytes from blood transfusion or disease
• CO poisoning
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Serious and sometimes fatal
Compete with O2 when attaching to hemoglobin
Causes the cells to be _______________________________.
Symptoms: HA, dizziness, drowsiness, and unconsciousness
LEUKOCYTES
• Do you remember covering this? You should… 
• Fight infection
• Phagocytosis – white cells surround, engulf and
digest harmful bacteria
• Basophils produce heparin – an anticoagulant
• Diapedesis – when white cells move through
capillary walls into neighboring tissues
INFLAMMATION
• Body’s reaction to chemical and physical trauma
(cut or heat)
• Pathogenic – disease producing microorganisms
that can cause infection
• Examples: bacteria, fungi, protozoa, and viruses
• Symptoms – redness, local heat, swelling, and pain
• Why? Due to irritation by bacterial toxins, increased
blood flow, congestion of blood vessels, and
collection of plasma in tissues (edema)
• See figure 12-2 pg. 246
INFLAMMATION TERMS
• Pus
• Cream-colored liquid formed from a combination of dead tissue,
dead and living bacteria, dead leukocytes, and blood plasma
• Abscess
• Pus-filled cavity below the epidermis
• Pyrogens
• Chemicals release when there is inflammation
• Circulate to the hypothalamus and affect the temperature control
center
• Pyrexia
• Raise in body temperature (fever) caused by pyrogens
• Leukocytosis
• Increase in the white blood cell count, above 10,000
• Leukopenia
• Decrease in the normal amount of WBCs
THROMBOCYTES
(PLATELETS)
• Again, covered previously
• Synthesized in red marrow
• Necessary for the initiation of the blood clotting
process
• What is the normal count?
• Is it the smallest or largest of the solid components
of blood?
• What is a “platelet plug”?
COAGULATION
• Blood clotting
• Depends on thrombocytes
• Clotting must occur to stop bleeding when there is a cut or
other injury
• When a blood vessel or tissue is injured, platelets and injured
tissue release thromboplastin
• Chain reaction follows and involves the release of
thromboplastin, prothrombin, thrombin and fibrinogen
• Fibrin creates a mesh that traps red blood cells, platelets and
plasma, creating a blood clot
• Anticoagulants prevent blood clotting and must be
neutralized
• Antithromboplastin and antiprothromin (heparin)
• *Prothrombin and fibrinogen are manufactured in the liver so
serious liver disease may interfere with blood clotting process*
CLOTTING TIME
• Time it takes for blood to clot
• Clotting time for humans is from 5-15 minutes
• Useful to know a patient’s clotting time before
surgery
• See figures 12-3 and 12-4 on pages 248 and 249
regarding clotting.
BLOOD TYPES
• Four major types, determined by presence or absence of an
antigen on the surface of the red blood cell
• A, B, O, AB
• Inherited from parents
• Determined by the presence (or absence) of the blood protein
antigen (found on the surface of RBCs)
• Type O has neither A or B and AB has both
• Antibody – a protein in the plasma that will inactivate a foreign
substance that enters the body
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Someone with type A blood has B antibodies
Type B blood has A antibodies
Type AB blood has no antibodies
Type O blood has A and B antibodies
• Universal donor: O• Universal recipient: AB+
• See table 12-4 page 249
RH FACTOR
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Red cells may also contain Rh factor
Rh positive (+) are those with the factor
Rh negative (-) are those without Rh factor
85% or North Americans are Rh +
• READ Rh Factor page 248-249