Review… Let’s look at… Figure 1-8 Figure 1-13 Figure 1-9 Figure1-10

The CIRCULATORY system… “Closed”… an understanding achieved by William Harvey in the seventeenth century. Circulates blood. Blood is a tissue. What is a tissue, what is in this tissue, and how do we know?

Definition… ( examine it critically )

Blood: the fluid that circulates in the heart, arteries, capillaries, and veins of a vertebrate animal carrying nourishment and oxygen to and bringing away waste products from all parts of the body Lymph: a pale, coagulable fluid that bathes the tissues, passes into lymphatic channels and ducts, is discharged into the blood by way of the thoracic duct, and consists of liquid portion resembling blood plasma and containing white blood cells but normally no red blood cells. Plasma: the fluid part of blood or lymph as distinguished from suspended material Serum: The watery portion of an animal fluid remaining after coagulation.

“Formed elements” = cells There are two types of cells: red blood cells (or erythrocytes) white blood cells (or leukocytes) –There are two types of leukocytes: »Granulocytes (70%) »Agranuloctyes (30%)

Granulocytes are: neutrophils, eosinophils, & basophils Agranulocytes are: lymphocytes & monocytes

“THE CENTRAL CELL OF THE IMMUNE SYSTEM IS THE LYMPHOCYTE, WHICH ACCOUNTS FOR ROUGHLY 25% OF WHITE BLOOD CELLS IN THE BLOOD AND 99% OF THE CELLS IN THE LYMPH.”

An average sized, adult, human male has about 6 quarts (5.6 liters) of blood. RBC: about x 10 6 / cubic millimeter; exchange O 2 and CO 2 ; develop in bone marrow; 120 day life time; destroyed in spleen... leukocytes: about 5, ,000/ cubic millimeter; (the number increases with infection) leukemia: an extraordinary and prolonged proliferation of leukocytes; usually fatal... leukopenia: a sharp decrease in number of leukocytes; also fatal due to a loss of defense...

Note these equivalencies… 1 liter = 1000 cubic centimeters = 1000 milliliters 1 milliliter = 1 cubic centimeter 1 milliliter = 1000 cubic millimeters 1 microliter = 1 cubic millimeter

OK… that’s who the cells are… But where do they originate?

Stimuli Multi Lineage Colony Stimulating Factor (Multi-CSF) a.k.a. IL-3 (interleukin-3) Granulocyte-Macrophage Stimulating Factor (GM-CSF) Macrophage Colony Stimulating Factor (M-CSF) Granulocyte Colony Stimulating Factor (G-CSF) ErythroPOietin ( EPO )

Where do the cells go?