The River of Life- Blood

Blood – Did You Know… An average adult has approximately 4.7 L (5 quarts) of blood. Blood comprises about 8% of a person’s total body weight. Blood travels 60,000 mi (96,540 Km) per day in your body. 15 million blood cells die every day and have to be replaced.

What is the Composition of Blood? Blood is about 78% liquid and 22% solids Four Major Components of Blood –Plasma –Red Blood Cells (RBC) –White Blood Cells (WBC) –Platelets

Is Blood a Tissue??? What is the definition of a tissue? –An integrated group of cells with a common function, structure, or both. How is blood considered a tissue?

Blood Plasma—The Liquid of Life Composition: – 90% water –Ionic salts (electrolytes) –Soluble proteins Functions: –Helps maintain homeostatic balance –Allows for the correct function of muscles and nerves –Transports soluble substances –Carries factors needed for blood clotting

Plasma Transports: Nutrients Electrolytes Hormones Antibodies Clotting factors Metabolic wastes Dissolved Gases: oxygen and carbon dioxide

Red Blood Cells (Erythrocytes) Most abundant blood cell 1 Billion per drop of blood or 5,200,000,000 per mL Mature cells lack a nucleus Average Lifespan: 120 Days Used with permission of Brian Garrigan

Red Blood Cell Facts Can be frozen for ten years Hemoglobin makes up 33% of cell mass Primary function is to carry oxygen Helps to remove carbon dioxide Produced in bone marrow Travel single file inside capillaries

White Blood Cells (Leukocytes) Types –Monocyte –Neutrophil –Lymphocyte –Basophil –Eosinophil See Pictures of These Cells

White Blood Cell Facts Largest of the blood cells Normally 5000 to 10,000 per mL Variable life span – from a few days to years Produced in bone marrow Part of the immune system Increase in number when infection is present

NEUTROPHIL MOST OF YOUR WBCS ARE NEUTROPHILS BONE MARROW PRODUCES TRILLIONS OF THEM EVERYDAY, THEY GENERALLY LIVE LESS THAN A DAY ATTRACTED TO FOREIGN PARTICLES, INFLAMMATION, AND BACTERIA SEARCHES OUT AND DESTROYS! WHAT DO YOU THINK PUS IS?

MONOCYTES MONOCYTES END UP BEING CALLED A VARIETY OF NAMES SUCH AS MACROPHAGES AND DENDRITES THESE WBCS LIKE TO CLEAN UP THEY INGEST BACTERIA, MICROBES, DUST, SMOKE, DEAD NEUTROPHILS - PHAGOCYTOSIS ANIMATION t/cellstructures/cell.swfhttp:// t/cellstructures/cell.swf

White Blood Cells—Functions Monocytes and Neutrophils: Fight bacteria and other foreign materials Signal other immune cells that foreign material is inside body

EOSINOPHILS AND BASOPHILS MUCH LESS COMMON EOSINOPHILS FOCUS ON PARASITES! BASOPHILS CARRY HISTAMINE AND HELP CAUSE INFLAMMATION WHY WOULD INFLAMMATION HELP AN INFECTION?

White Blood Cells—Functions Eosinophils Kill multicellular parasites (e.g. blood fluke) Basophils Involved in development of allergies

White Blood Cells—Functions Lymphocytes: Destroy abnormal cells Produce antibodies Moderate immune response

Invader antigens are everywhere! What does it need to get by? Skin! neutrophils Monoctyes (macrophages) T - Helper lymphs More T - Helper lymphs! Cytotoxic T lymphs B lymphs Memory B cells Plasma B cells Antibodies!! Invader dies! Invader dies!! Invader dies!!

Platelets (Thrombocytes) Formed in bone marrow Not cells, are fragments of precursor cells Lifespan—10 Days Help blood clot by forming “platelet plugs.” Stimulate other clotting factors Approximately 250,000 per mL of blood Lack a Nucleus

View of a simulated blood smear Used with permission of Ken Hoge

Questions 1. What is the general composition of human blood? 2. Why is blood classified as a tissue? 3. What are the characteristics and function of red blood cells? 4. What are the characteristics and functions of white blood cells? 5. What are the characteristics and function of platelets?