Blood notes PLATELETS & PHYSIOLOGY OF BLOOD

Human Blood Fact There are 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 O2 ? erythrocyte (rbc)

What is hematopoiesis? erythrocyte (rbc) production What controls erythrocyte production? erythropoietin Where is erythropoietin made? kidneys when O2 level is low What does Hb do? carries O2 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/mm3 essential for clotting life span: 10 – 12 days, removed by phagocytes

NON LIVING PARTS OF BLOOD PLASMA 90% water, transparent, amber color PLASMA PROTEINS (3) 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 CO2 & O2 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

begins about 30 seconds after injury 3. Coagulation Phase – a.k.a. “Blood Clotting” 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