1. HEMATOLOGY
STRUCTURE

2. iNTRODUCTION Adult’s body has 8-10 pints of blood on average
A loss of more than 2 pints at one time leads to a serious condition
How much blood is “taken” when you donate blood?
1 pint which equals approx. 1 pound

3. COMPOSITION Blood is made of: Plasma Serum Cellular components
Liquid portion of blood without its cellular elements
Serum
Name given to plasma after a blood clot is formed
Serum = plasma – (fibrinogen + prothrombin)
What are fibrinogen and prothrombin? (clue…look in your book!)
Cellular components
Erythrocytes, leukocytes, thrombocytes
What are each?

4. Cellular elements of blood (look at figure 12-1 pg 242 also)

5. Blood plasma Straw-colored Comprising about 55% of the blood volume!
Contains 6 substances:
Water
Plasma proteins (all are formed in the liver)
Nutrients
Electrolytes
Hormones, vitamins, and enzymes
Metabolic waste products

6. Realistic view of blood sample

7. water Makes up about 92% of the total plasma volume
Maintained by the kidneys and by water intake and output

8. Plasma proteins 3 proteins: Fibrinogen Serum albumin Serum globulin
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
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

9. Nutrients electrolytes
Absorbed from the digestive tract
Glucose, fatty acids, cholesterol, and amino acids are dissolved in the blood plasma
Most abundant are sodium chloride and potassium chloride
Come from foods and chemical processes occurring in the body

10. Hormones, vitamins, enzymes waste products
Found in very small amounts in the blood plasma
Generally help the body control its chemical reactions
All of the body’s cells are actively engaged in chemical reactions to maintain homeostasis
Waste products are formed and subsequently carried by the plasma to the various excretory organs
What are the excretory organs?

11. Erythrocytes Shape: biconcave discs, donut-shaped
Normal count ranges from for men and for women
Erythropoiesis: manufacture of RBCs
Vitamin B12 , folic acid, copper, cobalt, iron, and proteins are needed for production
Live for 120 days and broken down by the spleen and liver
Hemoglobin: breaks down into globin (protein) and heme (iron)
Provides the characteristic red color
Transports oxygen to the tissues and some carbon dioxide away
Normal levels are for men and for women

12. leukocytes Larger than RBCs and granular or agranular
Normal count averages from 3,200-9,800
Manufactured in bone marrow and lymphatic tissue
Body’s natural defense against injury and disease
2 major groups of cells:
Granulocytes – live only a few days
Agranulocytes – live for a few days to several years

13. granulocytes Neutrophils Eosinophils Basophils
Phagocytize bacteria with lysosomal enzymes
Phagocytosis: process where WBCs surround, engulf, and digest harmful bacteria
Eosinophils
Phagocytize the remains of antibody-antigen reactions
Increase in great numbers in allergic conditions, malaria, and in parasite or worm infestations
Basophils
Activated during an allergic reaction or inflammation
Produce histamine and heparin
Histamine and heparin do what?

14. agranulocytes Lymphocytes Monocytes B-lymphocytes: made in bone marrow
T-lymphocytes: made in the thymus gland, lymph nodes, and spleen
Both help the body by making and releasing antibody molecules and by protecting against the formation of cancer cells
Monocytes
Formed in the bone marrow and spleen
Assist in phagocytosis and are able to leave the bloodstream and attach to tissues (where they become tissue macrophages or histiocytes)
Histiocytes help wall off and isolate infected areas

15. To summarize leukocytes, they help to protect the body from injury and infection by:
Phagocytosis and destruction of bacteria
Synthesis of antibody molecules
“cleaning up” of cellular remnants at the site of inflammation
Walling off of the infected area
See tables 12-2 and 12-3 pg 245

16. Thrombocytes (Blood platelets)
Smallest of the solid components of the blood
Not cells but fragments of the megakaryocytes (see figure 12-1 again)
Normal count ranges from 250,000 to 450,000
Function in the initiation of the blood clotting process
When a cut or wound occurs, platelets are stimulated to produce sticky projecting structures, that create a “platelet plug” to stop the bleeding