PUMP IT UP NCSO Coaches Clinic THE HEART ANATOMY OF THE HEART Base - Superior end Apex - Inferior pointed end (left ventricle); rests on the diaphragm ANATOMY OF THE HEART • Pericardium – tough serous (connective tissue) membrane surrounding the heart HEART WALL • Three layers: – Epicardium/ Visceral pericardium • Outer connective tissue layer (protection) – Myocardium: • Thick middle layer • Cardiac muscle: contracts to pump blood ENDOCARDIUM – Thin inner layer composed of simple squamous epithelium - reduces friction for easier blood flow HEART CHAMBERS • Left & Right Atrium (Atria): Receiving chambers – Smaller with less muscle • Left & Right Ventricles: discharging chambers – Left has thicker muscle layer than right HEART VALVES • Valves open as blood is pumped through • Close to prevent backflow • Two types are structurally different ATRIOVENTRICULAR (AV) VALVES • Right AV- Tricuspid Valve- three cusps of endocardium • Left AV – Bicuspid/ Mitral valve – two cusps of endocardium Right AV Valve Left AV Valve CORDAE TENDINAE • Hold the AV valves in place • Also called the “heart strings” SEMILUNAR VALVES • PULMONARY - junction of right ventricle and pulmonary arteries • AORTIC - junction of left ventricle and aorta THE CARDIAC CYCLE • Produces the “lub-dup” sounds of a heartbeat • “lub” = closing of AV Valves • “dup” = closing of semilunar valves BLOOD PATHWAY THROUGH THE HEART • Pulmonary Circulation: between heart and lungs • Systemic Circulation: between heart and capillary beds BLOOD PATHWAY THROUGH THE HEART • Deoxygenated blood from body enters right atrium via the superior/ inferior vena cava • R. Atrium R. AV valve R. Ventricle pulmonary semilunar valve pulmonary trunk branches into left and right pulmonary arteries (4 total) to the lungs While in the lungs CO2 diffuses out of the blood and oxygen diffuses into the blood and is transferred to RBC’s BLOOD PATHWAY THROUGH THE HEART • L&R Pulmonary veins (4 total) deliver oxygenated blood to the left atrium • L. Atrium L. AV valve L. Ventricle aortic semilunar valve oxygenated blood to the body via the aorta BLOOD COMPOSITION • Hematocrit –volume percentage (%) of red blood cells • Plasma - 46-63% • Formed elements – 37-54% PLASMA • Non – living fluid matrix – 92% water – 7% plasma proteins – 1% other solutes • pH 7.35 to 7.45 – slightly alkaline RED BLOOD CELLS (ERYTHROCYTES) • About 1/3 of all body cells are RBC’s •Outnumber WBC’s 1000 to 1 •One drop of contains ~ 260 million •Males have higher numbers than females – androgens promote RBC production RBC STRUCTURE • Small size and “doughnut” shape provide large surface area to volume ratio – Increases gas transport and diffusion rate – Flexibility to squeeze through capillaries • Lack organelles – cannot undergo cell division – Life span about 120 days RBC FUNCTION - Contain ~ 250 million hemoglobin molecules – iron bearing protein that transports the bulk of the oxygen WHITE BLOOD CELLS (LEUKOCYTES) – Account for less than 1% of total blood volume – Contain a nucleus – Defend against bacteria, viruses, parasites and cancer cells WBC CHARACTERIS TICS – Diapedesis - ability to slip in and out of blood vessels – Positive chemotaxis – ability to locate areas of tissue damage and infection by responding to chemicals diffused from the damaged cells WBC TYPES Granular leukocytes Agranular leukocytes Most numerous Found in lymphoid tissue Numbers increase during prolonged infections Least numerous • Needed for blood clotting PLATELETS(T HROMBOCYTE • Megakaryocytes - platelets break off from the S) larger cell • Typical platelet count ~ 300,000/mm3 RED BLOOD CELLS (ERYTHROCYTES) • About 1/3 of all body cells are RBC’s • Outnumber WBC’s 1000 to 1 • One drop of contains ~ 260 million • Small size and “doughnut” shape provide large surface area to volume ratio – Increases gas transport and diffusion rate – Flexibility to squeeze through capillaries RED BLOOD CELLS • Lack organelles – cannot undergo cell division – Life span about 120 days • Contain ~ 250 million hemoglobin molecules – iron bearing protein that transports the bulk of the oxygen SICKLE CELL ANEMIA • Genetic disorder • Highest incidence in people of African descent • Evolutionary adaptation for surviving malaria –RBC’s have shorter life span, less flexible, can’t carry as much oxygen, “sickle shaped” • People are generally tired and have painful attacks • Limited activity WHITE BLOOD CELLS (LEUKOCYTES) – Account for less than 1% of total blood volume – Contain a nucleus – Defend against bacteria, viruses, parasites and cancer cells WBC CHARACTERISTICS – Diapedesis - ability to slip in and out of blood vessels – Positive chemotaxis – ability to locate areas of tissue damage and infection by responding to chemicals diffused from the damaged cells Most numerous Found in lymphoid tissue Numbers increase during prolonged infections Least numerous PLATELETS(THROMBOCYTES) • Needed for blood clotting • Megakaryocytes - platelets break off from the larger cell • Typical platelet count ~ 300,000/mm3 TYPES OF BLOOD VESSELS Arteries: Vessels that carry blood away from the heart *High pressure Veins: Vessels that return blood to the heart *Valves to prevent backflow *Low pressure TYPES OF BLOOD VESSELS • Arterioles – branch off arteries – Provide blood to more than 10 million capillaries • Venules – formed as capillaries join together as they leave the tissues TYPES OF BLOOD VESSELS • Capillaries – ~ diameter of one RBC – Capillary beds supply tissues of the body with gases & nutrients ATHERSCLEROSIS • Build up of cholesterol as a plaque in artery/ arteriole walls • May lead to heart attack or stroke/ high blood pressure MYOCARDIAL INFARCTION (HEART ATTACK) • Lack of blood flow through coronary arteries causes death of heart tissue RESPIRATORY FUNCTION • Oxygenates blood for delivery to the cells • Removes carbon dioxide (waste product) from blood • The Nose – only externally visible part of the system • Nostrils (external nares) – air enters the body FUNCT IONAL ANATO MY OF TRACHEA • Also called the windpipe • Lined with ciliated mucosa to propel mucus loaded with dust and other foreign bodies away from the lungs and to the throat • Rigid walls enforced with C – shaped rings of hyaline cartilage • Keeps trachea open during the pressure changes that occur during breathing LUNGS • Relatively large organs which occupy the thoracic cavity • Soft and spongy • Apex – located near clavicle • Base – rests on the diaphragm RESPIRATORY ZONE • Only site of gas exchange in the lungs • Structures include the alveoli, alveolar ducts, alveolar sacs and respiratory bronchioles MECHANICS OF BREATHING RESPIRATORY MEMBRANE • Also called the air-blood barrier • Gas flows past one side and blood past the other • Gas exchange occurs by diffusion through this membrane • Oxygen passes from the alveolar air into the RBC’s and carbon dioxide enters the alveoli from the blood COPD - (CHRONIC OBSTRUCTIVE PULMONARY DISEASE) COPD – COMMON FEATURES • History of smoking • Dyspnea – labored breathing that gets progressively worse • Coughing/ frequent pulmonary infections • Ultimately develop respiratory failure EMPHYSEMA • Lung tissue weakened and destroyed • Air spaces become larger • More difficult for air to be exchanged in the lungs • Lungs become less elastic • Over time it becomes more difficult to release carbon dioxide and to obtain oxygen. CHRONIC BRONCHITIS • • • • • Cough – 3 months to 2 yrs Increased mucus in lumen Chronic inflammation Chronic thickening of the bronchial walls Narrowed passageways ASTHMA • Chronically inflamed, hypersensitive bronchial passages • Respond to multiple irritants with coughing, wheezing and dyspnea (labored breathing) CYSTIC FIBROSIS • Defective gene causes mucus secretions to become thick and sticky disrupting breathing & digestion LUNG CANCER • Most preventable (over 70% of cases are caused by smoking) • High mortality rate after diagnosis