THE CARDIORESPIRATORY SYSTEMChapter 9Cardiorespiratory SystemWhat are the functions of the cardiorespiratory system?–Transport O2 to tissues and removal of waste–Transport of nutrients to tissues–Regulation of body temperatureCardiorespiratory SystemWhat are the components of the cardiorespiratory system?Cardio-Heart = a pump between external and internal respirationBlood Vessels = transportationRespiratoryLungs = gas exchangeCardiovascular SystemHeartBlood vesselsTHE HEARTPULMONARY CIRCUITSYSTEMIC CIRCUITTHE HEARTFOUR CHAMBERS2.Right atria - blood from systemic system to...3.Right ventricle - blood to pulmonary system and then to...4.Left atria - blood from pulmonary system to...5.Left ventricle - blood to systemic system and then to...right atria (and repeat)Cardiovascular SystemSystemic circuit" Which side of the heart is part of the systemic circuit?" What is the oxygen content of the blood as it leaves the heart (high or low)?Pulmonary circuit" Which side of the heart is part of the pulmonary circuit?" What is the oxygen content of the blood as it leaves the heart (high or low)?•Blue section shows blood flow through the right side of the heart•Red section shows blood flow through the left side of the heartBLOOD FLOW THROUGH THE HEARTMYOCARDIUMor Cardiac MuscleWhat is the myocardium?Why is the left ventricle the most powerful and largest of the chambers?Right LeftWall WallMYOCARDIUM Intercalated disksWhat are they?What is their function?CONTROL OF THE HEART - INTRINSICCONTROL OF THE HEARTWhat part of the heart is referred to as the pacemaker of the heart?What is the function of the A-V node?What is an electrocardiogram?Electrocardiogram (ECG or EKG)TERMSDepolarization: stimulation of the myocardiumRepolarization: recovery of the myocardium from stimulationCONTROL OF THE HEART - ECGMEDULLAControl Center1.Neural input to medullaHigher brain centersReceptorsBaroreceptors (blood vessels)Stretch receptors (heart)Chemoreceptors (blood vessels)Mechanoreceptors (muscles/joints)2.Neural output from the medullaSympathetic nervous systemParasympathetic nervous systemMEDULLAControl CenterCONTROL OF THE HEARTNEURAL CONTROL•Parasympathetic Nervous System acts through the vagus nerve. •What affect does the vagus have on heart rate?•What affect does the Sympathetic Nervous System have on heart rate?HORMONAL CONTROL•What affect do the hormones epinephrine and norepinephrine have on heart rate?HEART FUNCTION - Heart RateHeart RateDefinition?What is a typical resting heart rate?HEART FUNCTION - Cardiac Cycle Cardiac Cycle: Events that occur between two consecutive heartbeats (systole to systole) What is Diastole? What is Systole?HEART FUNCTION - Cardiac CycleHEART FUNCTION - Heart RateWhy does heart rate increase during exercise?How is heart rate increased?HEART FUNCTION – Stroke VolumeWhat is stroke volume?What happens to stroke volume during exercise?How is stroke volume increased?HEART FUNCTION - Cardiac Output (Q)What is cardiac output?Cardiac Output = Heart Rate x Stroke VolumeExample: HR of 72 beats/minute x SV of 70 mL/beat[the beat(s) cancel out] Therefore, Q = 72 x 70 or 5,040 mL/min or 5.040 L/minHEART FUNCTION•Heart Rate•50-75 beats per minute•Stroke Volume (SV)•60-100 milliliters per beat (ml/beat)•Cardiac Output (Q)•4500-5000 milliliters per minute•4.5-5 liters per minute (L/min)How is cardiac output increased during exercise?Why is cardiac output increased during exercise?HEART FUNCTION - Cardiac Output (Q)a-v O2 DifferenceOxygen Extraction at RestArteries20 ml or oxygen in every 100 ml of arterial bloodVeins15 ml/100 ml of blood.How much oxygen did the muscles use?This amount is call the a-vO2 difference.THE VASCULAR SYSTEM (Circulation) Arteries Arterioles Capillaries Venules & VeinsTHE VASCULAR SYSTEM - ArteriesHow do arteries differ from other blood vessels?THE VASCULAR SYSTEM - ArteriolesUnique?Smooth muscle sphinctersFunction?Blood distributionVasodilationVasoconstrictionTHE VASCULAR SYSTEM - CapillariesWhat makes capillaries unique from other blood vessels?THE VASCULAR SYSTEM - VeinsWhat makes veins unique from other blood vessels?Muscle PumpMuscle PumpBLOOD PRESSURESystolic is the pressure in the __________ when the heart is __________.Diastolic is the pressure in the __________ when the heart is __________.What is a normal resting blood pressure?What happens to systolic blood pressure during exercise? Why?Why is high blood pressure at resting unhealthy?BLOOD PRESSURETHE BLOOD Transportation: gas, nutrients, and wastes Regulates temperature Others What are some of the functions of the blood?THE BLOOD – FORMED ELEMENTSRed blood cells. What do they do?White blood cells. What do they do?Platelets. What do they do?THE BLOOD – BLOOD VOLUMETHE BLOOD - HematocritWhat is Hematrocrit?Ratio of formed elements (mostly RBC) to the total blood volume What is a typical