Blood notes PLATELETS PHYSIOLOGY OF BLOOD Human Blood

Blood notes PLATELETS & PHYSIOLOGY OF BLOOD

Human Blood Fact There about 5 liters or 1. 3 gallons of blood in the average adult body.

Why are red blood cells shaped like donuts without the hole in the middle? the dents in the cells add to the surface area, allowing more oxygen and carbon dioxide to pass in and out of the cell.

Review What is another name for a rbc? erythrocyte A wbc? leukocyte What are the formed elements? living blood cells in plasma – rbc’s (erythrocyte), wbc’s (leukocyte), platelets Which blood cell carries O 2 ? erythrocyte (rbc)

What is hematopoiesis? erythrocyte (rbc) production What controls erythrocyte production? erythropoietin Where is erythropoietin made? kidneys when O 2 level is low What does Hb do? carries O 2 in rbc What is it called when a wbc squeezes through a capillary? diapedesis

What are the 3 types of granulocytes? neutrophils, basophils, eosinophils What are the 2 types of agranulocytes? monocyte, lymphocyte What is responsible for an organ transplant rejection? lymphocyte

• PLATELETS • aka: THROMBOCYTES • inactive platelets • activated platelets

• 250, 000 – 500, 000/mm 3 • essential for clotting • life span: 10 – 12 days, removed by phagocytes

• NON LIVING PARTS OF BLOOD • PLASMA PROTEINS (3) • 90% water, transparent, amber color 1. ALBUMIN: osmotic pressure 2. GLOBULIN: transports lipids 3. FIBRINOGEN: clotting

• ELECTROLYTES (salts/minerals) • must have these for cells to function • sodium, potassium, calcium, magnesium, chloride, phosphate • NUTRIENTS • glucose, amino acids, lipids, vitamins • WASTE MATERIALS • sent to kidneys • RESPIRATORY GASES • CO 2 & O 2 • OTHER • enzymes, hormones

• PHYSIOLOGY OF BLOOD • HEMOSTASIS • stopping bleeding – clotting – reaction to injury/wound • keeps us from bleeding to death internally & externally • Multi step process 1. Vascular Phase • cutting blood vessel wall triggers SEROTONIN to cause a contraction in the tunica media – smooth muscle • contraction is called a VASCULAR SPASM – can last 30 minutes

2. Platelet Phase • platelets begin to stick to endothelium and each other • a platelet plug is formed

3. Coagulation Phase – a. k. a. “Blood Clotting” • begins about 30 seconds after injury • involves a series of steps in which blood cells and platelets are trapped in a protein mesh forming a BLOOD CLOT

• Wound healing • wound is sealed & then healed by regeneration • using pressure and/or dressings speeds up wound healing