Cardiovascular Chapter

Cardiovascular & Respiratory Systems

Cardiovascular System Heart, vessels, fluid Transport system Gas exchange Nutrients & wastes Hormones Regulate body temperature Makes ………?

Cardiovascular System 3 main components: Pump- heart Beats approx 100,000 thousand times per day 8,000 liters of blood Vascular- blood vessels 60,000 miles Arteries- away from heart Veins- to the heart Fluid- blood & components Fluid= plasma Fluid connective tissue

Circulatory Systems Closed circulatory Capillary beds Pump, vascular, fluid= Cardiovascular system Closed space Continuous flow High pressure, more efficient Vertebrates Capillary beds anastomose

Blood Paths Double circulation system Pulmonary circuit Flow between heart & lungs Exchange of CO2 & O2 Systemic circuit Flow between heart & body Coronary circuit Flow to heart muscle

Pulmonary Circuit Movement to & from lungs Deoxygenated blood (70%) becomes oxygenated blood (98%) Right side of heart Pulmonary pump Pulmonary artery Blood to lungs Only artery with deoxygenated blood Pulmonary vein Blood to heart Only vein with oxygenated blood

Coronary Circuit

Figure: 12-01UN Title: Pathway of blood through the body. Caption:

Heart- Artery- Arteriole- Capillary- Venuole- Vein- Heart

Blood Mixture of components in solution Fluid component 5 Liters Fluid component Plasma Cellular component (formed elements) Erythrocytes Leukocytes Thrombocytes

Plasma 55% of blood Matrix of fluid connective tissue No protein fibers Dissolved proteins Plasma denser than water Contains Water 90% Electrolytes Calcium Proteins Serum Plasma minus clotting proteins (ie fibrinogens)

Plasma

Cellular Elements 45% of blood Erythrocytes Leukocyte Thrombocytes Red blood cells Leukocyte White blood cells Thrombocytes Platelets

Platelets Aka thrombocytes Anuclear Packets of cytoplasm Function in clotting response work with fibrinogen- fibrin Form blood clots Hemophilia Absence of clotting factors

Agglutination

Erythrocytes Bulk of blood cells (99.9%) Highly specialized Hematocrit % of RBC Highly specialized Hemoglobin on surface Transports gases via diffusion No organelles High sa/ volume No cell division

Erythrocytes Structure Concave surface maximizes surface area Maximizes ability to transport oxygen & carbon dioxide Hemoglobin Heme Provides flexible to fit through capillaries

Red Blood Cell Shape is distensible (Bendy!)

Anemia Deficiency in Red blood cells or in Hemoglobin Reduced ability to transport Oxygen to tissues Most common blood disorder Results from Loss of blood Injury, menstruation, rbc destruction Iron deficiency Sickle cell anemia Genetic abnormality of hemoglobin Causes abnormal shape in deoxygenated cells

Leukocytes Immune function Larger in size Contains organelles Fight pathogens Remove waste, toxins, & abnormal or damaged cells Larger in size Contains organelles Nucleus No hemoglobin Many different types Less abundant in blood stream

Leukocytes

Leukocytes Migrate in body Found in extracellular matrix Concentrated in area of infection or disease Amoeboid movement Migrate out of the bloodstream Attracted to chemical signals Generalized & specialized functions based on cell type Lymphocytes- specific immunity

Clean Up

Heart Muscular pump 4 chamber system Valves- regulate flow Prevents mixing of o/d blood 2 atria- receives 2 ventricles- pumps away Valves- regulate flow Uses pressure to circulate blood throughout body

Heart Structure 5” X 3.5” X 2.5” (3g) Located in thoracic cavity Mediastinum- space between pleural cavities Surrounded by pericardium Serous membrane Visceral pericardium Parietal pericardium Base Broad superior region Apex Pointed tip of heart

Thoracic cavity

Parietal Pericardium

Heart wall 3 layers Epicardium Myocardium Endocardium Aka visceral pericardium Outer surface Myocardium Muscular wall of heart Cardiac muscle tissue CT, blood vessels, nerves Concentric layers Endocardium Inner surface & valves Endothelium Serous membrane

Myocardium

Epicardium

Endocardium

Intercalated Disk

Heart structure Atria (atrium) Ventricles Superior chambers Smaller Thinner walls Receives blood Ventricles Inferior chambers Larger Thick walls Pump to body/lungs

Great Vessels of Heart Vena Cava Pulmonary artery & vein Aorta Returns blood to rt atrium Superior vena cava Inferior vena cava Pulmonary artery & vein Blood flow to & from lungs Aorta Blood to body Coronary arteries Blood to heart

Coronary Artery

Coronary Artery Supplies Myocardium

Valves Ensure 1 way flow through heart Allow pressure build up Open & close passively due to pressure changes Atrioventricular valves Valves between atrium & ventricle Semilunar valves Right & left (Pulmonary & aortic) Between ventricle & vessels

Heart Valves

Atrioventricular Valves Aka AV valves Right AV aka tricuspid Left AV aka Bicuspid Between atrium & ventricles Open when heart relaxes Held closed by Chordae tendinae during contraction Dense connective tissue Prevents prolapse Papillary muscle Heart murmur

Tricuspid

Chordae Tendinae & Papillary Muscle

Papillary Muscle Anchors Valve

Semilunar Valves Between r/l ventricles & arteries Pulmonary Semilunar valve Right ventricle to r/l pulmonary artery Aortic Semilunar valve Left ventricle to aorta Close when blood back flows

AV Valve Function Valves close via blood pressure Open when heart relaxed (Diastole) Close during ventricular contraction (Systole) Blood pushed up against valve

AV Valves Review

Semilunar Valve Function Semilunar valves Closed during heart relaxation (Diastole) Ventricular contraction (Systole) increases pressure opens valves Ventricular relaxation allows blood to fall back- cusp fills & seals valve

Semilunar Valve

Heart Sounds Systole Diastole

Heart Murmur

Valve Prolapse http://heart.healthcentersonline.com/heartvalve/mitralvalveprolapse2.cfm