The Blood

QuickTime™ and a decompressor

are needed to see this picture.

Functions• Transport & Exchange

• Temperature Regulation

• Defense Against Disease (Immunity)

• pH Balance

• Fluid Volume Balance

Composition of the Blood• 8% of body weight• 55% fluid & 45% solid(formed

elements)

• Hematocrit - percent of RBC’s to total blood volume

• Normal value: ~45%

QuickTime™ and a decompressor

are needed to see this picture.

Composition of the Blood

Physical Characteristics of Blood

• pH = 7.35 - 7.45 (slightly alkaline)

• Viscosity = 5x more viscous than water

• Dissolved salts = salty fluid

QuickTime™ and a decompressor

are needed to see this picture.

Plasma• Content: 90 - 92% water + electrolytes, buffers, hormones, enzymes, pigments, & vitamins

QuickTime™ and a decompressor

are needed to see this picture.

Plasma

Plasma Proteins• Albumins - maintain viscosity & water

balance between tissues & blood

*large proteins cannot pass through capillaries but are able to take up water soluble wastes, therefore, food & oxygen leave capillaries while proteins stay and osmotic pressure is maintained

Plasma Proteins• Globulins - aid in defense against disease; associated with antibodies

• Lipoproteins - bind to fats and transport them around the body

Plasma Proteins

• Fibrinogen - changes from soluble to insoluble form during the clotting reaction

Plasma Proteins• Serum - plasma that has had fibrinogen (clotting proteins) removed

• Edema - fluid retention by tissues (swelling) often caused by abnormal loss of plasma proteins from bloodstream due to kidney problems

Solid Parts of the Blood• Erythrocytes =

RBC’s (red blood cells)

• Leukocytes = WBC’s (white blood cells)

• Thrombocytes = platelets

QuickTime™ and a decompressor

are needed to see this picture.

QuickTime™ and a decompressor

are needed to see this picture.

QuickTime™ and a decompressorare needed to see this picture.

Hematopoiesis• Process of blood cell formation

• Occurs in the red marrow

• Hematocytoblast = stem cell from which all formed elements of blood originate

Hematopoiesis

Hematopoiesis• RBC’s survive ~120 days

• Reticulocytes = immature red blood cells that still contains a nucleus & organelles

• Reticulocytes make up ~0.8% of all circulating RBC’s

Hematopoiesis• Hemoglobin - protein/pigment found in rbc’s that binds to oxygen

Hematopoiesis

• Erythropoietin - hormone that stimulates the bone marrow to produce more RBC’s; produced in the kidneys & released when oxygen levels in the blood decline

Erythropoietin & Blood Doping

QuickTime™ and a decompressor

are needed to see this picture.

Conditions that require more RBC’s

• Strenous muscular exercise

• Ascending to high altitudes

• Rise in environmental temperature

The End