440 likes | 560 Views
Principles of Animal Physiology. Circulatory Systems. Introduction. Components of circulatory systems Fluid - contains transport molecules and cells (blood or hemolymph) Pump - to move the fluid around Conduits (vessels) - to carry the fluid between pump and body tissues.
E N D
Principles of Animal Physiology Circulatory Systems Introduction • Components of circulatory systems • Fluid - contains transport molecules and cells (blood or hemolymph) • Pump - to move the fluid around • Conduits (vessels) - to carry the fluid between pump and body tissues
Principles of Animal Physiology Circulatory Systems Introduction • Types of circulatory systems
Principles of Animal Physiology Circulatory Systems Introduction • Open and Closed systems • Open circulation • Contains Hemolymph • Hemolymph moves from vessels to extracellular spaces among tissues • Hemocoel - extracellular spaces containing hemolymph • Hemolymph may be moved by body movements, cilia or flagella, or by hearts
Principles of Animal Physiology Circulatory Systems Introduction • Circulation in an open system
Principles of Animal Physiology Circulatory Systems Introduction • Open and Closed systems • Colsed circulation • Contains Blood • Blood moves through vessels but not among tissues • Capillaries - exchange of materials occur • Blood moved about the body by the heart or by body movements
Principles of Animal Physiology Circulatory Systems Introduction • Ciruclation in a closed system
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • Two components to circulatory fluids • Plasma • Watery, containing dissolved and dispersed molecules • Cellular elements • In hemolymph • Hemocytes - various cell types • Responsible for immune functions, clotting, oxygen transport • Blood • Erythrocytes - red blood cells for transporting oxygen • Leukocytes - white blood cells for immune response • Thrombocytes for platelets - for clotting
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • The Hematocrit • Percent of packed cell volume in whole blood • Human - 45% in males; 42% in females • White whale - 53% in females; 52% in males • Pekin duck - 45% at seal level; 56% at high altitude • Sriped bass - 39% at 5°C; 53% at 25°C
Principles of Animal Physiology Circulatory Systems Introduction • Plasma and Hematocrit volumes
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • Plasma in Circulatory Fluids • Contains 90% or more water • A medium for carrying organic and inorganic substances • Plasma proteins - 6-8% of plasma weight -osmotic pressure and buffering • Most abundant electrolytes - Na+, Cl-, HCO3-, K+, and Ca++ • Nutrients - glucose, amino acids, lipids, and vitamins • Waste - creatinine, bilirubin, urea • Dissolved gases • Hormones
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • Erythrocytes • Transport oxygen • Transport carbon dioxide • Oblong oval or biconcaved flattened discs • Flexible • Contain no nucleus, orgennelles, or ribosomes • Contain plasma and hemoglobin • Does not use the oxygen that they carry • Lifespan - 100 to 120 days
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • Erythrocytes
Principles of Animal Physiology Circulatory Systems Circulatory Fluids • Blood Cell Production (Hemopoiesis)
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Pumps • Flagella • Fluid moved by beating epithelial cells • Extrinsic muscle or skeletal pumps • Fluid moved by motion of skeletal muscles • May occur during locomotion • Peristaltic muscle pumps • Occurs during contraction of vessel muscle walls • Chamber muscle pumps • Hearts • Most have at least two chambers
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Types of pumps in animals
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Two chambered heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Dual Pumps in Avian and Mammalian Hearts • 4 chambers - 2 atria and 2 ventricles • Atria receive and store blood • Ventricles pump blood away from the heart • Veins return blood to the heart • Arteries take blood away from the heart • Septum is muscular tissue that separates the two sides of the heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Dual Pumps
Principles of Animal Physiology Circulatory Systems • Atria - holding chambers • Ventricles - produce pressure to drive blood through system • Arteries - low-resistance, little pressure loss, pressure resevoirs • Arterioles - high resistance, regulate blood pressure, distribute blood to various organs • Capillaries - site for nutrient and waste product exchange • Venules - nutrient and waste product exchange, regulates capillary blood pressure • Veins - low resistance conduits, facilitates flow back to the heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Heart Valves Ensure Unidirectional Blood Flow
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • The Mammalian Heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Blood flow through mammalian heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • The Mammalian Ventricles • Myocardium • Epicardium • Epicardium
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Mechanism of Valve Action
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Organization of Mammalian Cardiac Muscle Fibers • Intercalated discs • Desmosomes • Gap junctions • Functional syncytium • Myoglobin
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Conducting Pathway in Mammalian Heart • SA node • Internodal pathway • AV node • Bundle of His • Left & Right bundle branches • Purkinje fibers
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Conducting Pathway in Mammalian Heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Pacemaker Activity in Cardiac Autorhythmic Cells • Pacemaker cells • SA node • AV node • Bundle of His • Purkinje fibers • Pacemaker potential • Decrease in outward K+ current • Constant inward Na+ current • Increase in inward Ca++ current • Depolarization • Continued inward Na+ current • Influx of Ca++
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Pacemaker Activity of Cardiac Autorhythmic Cells
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Action Potential of Contractile Cardiac Muscle Cells • RMP about -90 mV • Rising phase - influx of Na+ • Initial repolarization - ↓PNA+; ↑PCa2+; ↓PK+ • Plateau - slow inward Ca2+ current; decreased K+ efflux • Repolarization - inactivation of Ca2+ channels; increase outward K+ current
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Action Potential and Tension Development in Cardiac Contractile Muscle Cell • Refractory period • Tetanus
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Action Potential of Contractile Cardiac Muscle Cells
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Comparison of action potential in different regions of the heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • The Electrocardiogram
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Mechanical Events of Mammalian Cardiac Cycle
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Mechanical Events of Mammalian Cardiac Cycle • Early Ventriclular Diastole • Late Ventricular Diastole • End of Ventricular Diastole - end-diastolic volume • Onset of Ventricular Systole • Isovolumetirc Venticular Contraction • Ventricular Ejection • End of Ventricular Systole - end systolic volume • Onset of Ventricular Diastole • Dicrotic notch • Isovolumetric Ventricular Relaxation • Ventricular Filling
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • The Cardiac Output • Cardiac out (CO) = volume of blood pumped by each ventricle per minute CO = HR x SV, HR = heart rate, SV = stroke volume Starling’s law of the heart • Increased filling pressure (volume) leads to increased cardiac output • If HR = 72 beats/min, SV= 0.07L/beat, then CO = 72 beats/min X 0.07L/min = 5.0 L/min
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • Autonomic innervation of the heart
Principles of Animal Physiology Circulatory Systems Circulatory Pumps • ACh • ↑APs interval of pacemaker cells →↓ HR • Negative chronotropic effect • ↓Velocity of conduction, may lead to AV • block → ectopic pacemaker • Nor(epinephrine) • ↑ heart rate via pacemaker cells • Positive chronotropic effect • ↑ strength of contraction (myocardial cells) • Positive inotropic effect
Principles of Animal Physiology Circulatory Systems • Autonomic control of SA node activity and heart rate
Principles of Animal Physiology Circulatory Systems • Control of cardiac output
Principles of Animal Physiology Circulatory Systems • Summary of factors influencing cardiac output
Principles of Animal Physiology Circulatory Systems • Blood pressure in various blood vessels of the systemic circulation
Principles of Animal Physiology Circulatory Systems • Relation btw. Velocity of blood flow and Xsectional area of vascular tree