What does the prefix 'angio-' refer to?; Vessel What is 'angiotensin'?; A substance that constricts blood vessels. What does the prefix 'ather-' refer to?; Porridge What is 'atherosclerosis'?; Deposits of plaque in arteries. What does the prefix 'brady-' refer to?; Slow What is 'bradycardia'?; Abnormally slow heartbeat. What does the prefix 'diastol-' refer to?; Dilation What is 'diastolic pressure'?; Blood pressure when the ventricle of the heart is relaxed. What does the prefix 'edem-' refer to?; Swelling What is 'edema'?; Accumulation of fluids in the tissues that causes them to swell. What does the suffix '-gram' refer to?; Something written What is an 'electrocardiogram'?; Recording of the electrical changes in the myocardium during a cardiac cycle. What does the prefix 'lun-' refer to?; Moon What is a 'semilunar valve'?; Valve with crescent-shaped flaps. What does the prefix 'myo-' refer to?; Muscle What is the 'myocardium'?; Muscle tissue within the wall of the heart. What does the prefix 'papill-' refer to?; Nipple What is a 'papillary muscle'?; Small mound of muscle projecting into a ventricle of the heart. What does the prefix 'phleb-' refer to?; Vein What is 'phlebitis'?; Inflammation of a vein. What does the prefix 'scler-' refer to?; Hard What is 'arteriosclerosis'?; Loss of elasticity and hardening of a blood vessel wall. What does the prefix 'syn-' refer to?; Together What is a 'syncytium'?; Mass of merging cells that act together. What does the prefix 'systol-' refer to?; Contraction What is 'systolic pressure'?; Blood pressure resulting from a single ventricular contraction. What does the prefix 'tachy-' refer to?; Rapid What is 'tachycardia'?; Abnormally fast heartbeat. How many liters of blood does the heart pump through the body each day?; 7,000 liters. How many times does the heart contract in an average lifetime?; 2.5 billion times. What is the order of blood flow through the blood vessels starting from the heart?; Arteries → arterioles → capillaries → venules → veins → back to heart. What components make up the cardiovascular system?; The heart and all blood vessels. What does the term 'cardiovascular' refer to?; Both heart and blood vessels. What is the function of the pumping action of the heart?; It transports blood through blood vessels. How many circuits do blood vessels form in the cardiovascular system?; Two circuits. What is the main function of the pulmonary circuit?; It transports oxygen-poor blood from the heart to the lungs and back to the heart. What happens to the blood in the lungs in the pulmonary circuit?; The blood picks up O2 and drops off CO2. What is the main function of the systemic circuit?; It transports oxygen-rich blood from the heart to all body cells and back to the heart. What does the blood deliver to cells in the systemic circuit?; Nutrients. What does the blood remove from cells in the systemic circuit?; Wastes. What type of blood does the left side of the heart contain?; Oxygen-rich blood. What type of blood does the right side of the heart contain?; Oxygen-poor blood. How many circuits does blood run through?; Two circuits. What are the two circuits blood runs through?; Pulmonary circuit to lungs and systemic circuit to body cells. What shape is the heart?; Cone-shaped. What type of pump is the heart?; A hollow, muscular pump. Where is the heart located?; In the mediastinum of the thoracic cavity, superior to the diaphragm. How many chambers does the heart have?; Four chambers. What are the upper chambers of the heart called?; Atria. What are the lower chambers of the heart called?; Ventricles. What is the function of the ventricles?; Pumping action. How does heart size vary?; Heart size varies with body size. Where does the heart lie?; The heart lies in the thoracic cavity. What is the average size of the heart?; The average size of the heart is 14 cm long and 9 cm wide. Where is the heart located in relation to the sternum?; The heart is posterior to the sternum. Where is the heart located in relation to the lungs?; The heart is medial to the lungs. Where is the heart located in relation to the vertebral column?; The heart is anterior to the vertebral column. Where does the base of the heart lie?; The base of the heart lies beneath the 2nd rib. Where does the apex of the heart lie?; The apex of the heart lies at the 5th intercostal space. What is the pericardium?; A covering over the heart and large blood vessels. What is the fibrous pericardium?; The outer layer that surrounds the double-layered serous membrane. Where is the parietal pericardium located?; Deep to the fibrous pericardium; it is the outer layer of the serous membrane. What is another name for the visceral pericardium?; Epicardium. What is the visceral pericardium?; The inner layer of the serous membrane attached to the surface of the heart. What are the three distinct layers of the heart wall?; Epicardium, Myocardium, Endocardium. What is another name for the Epicardium?; Visceral pericardium. Which layer of the heart wall is the outermost layer?; Epicardium. What is the composition of the Myocardium?; Cardiac muscle tissue. Which layer of the heart wall is the thickest?; Myocardium. What is the function of the Endocardium?; Forms the inner lining of all heart chambers. Which layer of the heart wall is the innermost layer?; Endocardium. What is the composition of the epicardium?; Serous membrane of connective tissue covered with epithelium and including blood capillaries, lymph capillaries, and nerve fibers. What is the function of the epicardium?; Forms a protective outer covering and secretes serous fluid. What type of tissue makes up the myocardium?; Cardiac muscle tissue separated by connective tissue and including blood capillaries, lymph capillaries, and nerve fibers. What is the primary function of the myocardium?; Contracts to pump blood from the heart chambers. What is the composition of the endocardium?; Membrane of epithelium and underlying connective tissue, including blood vessels. What is the function of the endocardium?; Forms a protective inner lining of the chambers and valves. How many chambers does the heart have?; Four chambers (2 atria and 2 ventricles). What are the characteristics of the atria?; Thin-walled upper chambers that receive blood returning to the heart. What are auricles in the heart?; Flap-like projections from atria that allow atrial expansion. What are the characteristics of the ventricles?; Thick-walled lower chambers that pump blood into arteries. What is the function of the right atrium?; Receives blood returning from the systemic circuit (from the superior and inferior vena cavae and coronary sinus); pumps blood to the right ventricle. What is the function of the right ventricle?; Receives blood from the right atrium; pumps blood to the lungs. What is the function of the left atrium?; Receives blood from the pulmonary veins; pumps blood to the left ventricle. What is the function of the left ventricle?; Receives blood from the left atrium; pumps blood to the systemic circuit. Where is the tricuspid valve located?; Right atrioventricular orifice. What is the function of the tricuspid valve?; Prevents blood from moving from the right ventricle into the right atrium during ventricular contraction. Where is the pulmonary valve located?; Entrance to pulmonary trunk. What is the function of the pulmonary valve?; Prevents blood from moving from the pulmonary trunk into the right ventricle during ventricular relaxation. Where is the mitral valve located?; Left atrioventricular orifice. What is the function of the mitral valve?; Prevents blood from moving from the left ventricle into the left atrium during ventricular contraction. Where is the aortic valve located?; Entrance to aorta. What is the function of the aortic valve?; Prevents blood from moving from the aorta into the left ventricle during ventricular relaxation. What is the function of the tricuspid valve in the human heart?; The tricuspid valve prevents backflow of blood from the right ventricle to the right atrium. What is another name for the mitral valve?; The mitral valve is also known as the bicuspid valve. Where is the aortic valve located?; The aortic valve is located between the left ventricle and the aorta. What is the role of the pulmonary valve?; The pulmonary valve controls blood flow from the right ventricle into the pulmonary arteries. What surrounds the origins of the pulmonary trunk and aorta, and the orifices between atria and ventricles?; Rings of dense connective tissue. What do the rings of dense connective tissue provide attachments for?; Heart valves and muscle fibers. What function do the rings of dense connective tissue serve during heart contraction?; They prevent excess dilation of heart chambers. What makes up the skeleton of the heart?; The rings of dense connective tissue along with other fibrous masses in the interventricular septum. What do the left and right coronary arteries supply blood to?; Tissues of the heart. What are the first two branches of the aorta?; The coronary arteries. What is the main topic of Figure 15.13?; Blood Supply to the Heart What is the cardiac cycle?; The events of a heartbeat. How do the heart chambers function during the cardiac cycle?; In a coordinated manner. What happens during atrial systole?; The atria contract while the ventricles relax (ventricular diastole). What happens during ventricular systole?; The ventricles contract while the atria relax (atrial diastole). How are heart actions regulated during the cardiac cycle?; Atria contract during atrial systole while ventricles relax, and then ventricles contract during ventricular systole while atria relax. What is a heart transplant?; Replacement of most of a failing heart with a donor heart. What is a Left Ventricular Assist Device (LVAD)?; A mechanical half-heart used temporarily until a donor heart is available. What is an implantable replacement heart made of?; Titanium and plastic. Who might receive an implantable replacement heart?; People who cannot have a heart transplant and do not have long to live. What does stem cell technology allow for in cardiac care?; Culturing of cardiac muscle tissue from altered somatic cells or stem cells. What future application may stem cell technology have in cardiac care?; Stem cell heart patches. What happens to the pressure in the heart chambers during a cardiac cycle?; It rises and falls. What causes the heart valves to open and close during the cardiac cycle?; Pressure changes. What happens to the ventricles during atrial systole and ventricular diastole?; The ventricles are relaxed. Which valves are open during atrial systole and ventricular diastole?; The A-V valves. Which valves are closed during atrial systole and ventricular diastole?; The semilunar valves. What percentage of blood flows passively from the atria into the ventricles during atrial systole and ventricular diastole?; About 70%. What happens to the remaining 30% of blood during atrial systole?; Atrial systole pushes it into the ventricles, causing ventricular pressure to increase. What happens to the A-V valves during ventricular systole and atrial diastole?; The A-V valves close. What prevents the cusps of the valves from bulging too far backward into the atria during ventricular systole?; The chordae tendineae. What happens to the atria during ventricular systole and atrial diastole?; The atria relax. Where does blood flow into the atria from during ventricular systole and atrial diastole?; From the venae cavae and pulmonary veins. What happens when the ventricular pressure increases during ventricular systole?; It opens the semilunar valves. Where does blood flow when the semilunar valves open during ventricular systole?; Into the pulmonary trunk and aorta. What causes the sounds of a heartbeat when heard through a stethoscope?; The closing of heart valves and vibrations associated with a sudden slowing of blood flow during contraction/relaxation of chambers. What is the first heart sound called and when does it occur?; The first heart sound is called 'lubb' and it occurs during ventricular systole. Which valves are associated with the 'lubb' sound?; The A-V valves. What is the second heart sound called and when does it occur?; The second heart sound is called 'dupp' and it occurs during ventricular diastole. Which valves are associated with the 'dupp' sound?; The pulmonary and aortic semilunar valves. What is a heart murmur?; An abnormal heart sound derived from incomplete closure of cusps of a valve. What does Figure 15.15 illustrate?; Regions at which sounds of heart valves can be heard. What do cardiac muscle cells form?; Branching networks. What is the function of intercalated discs between cardiac muscle cells?; They contain gap junctions that allow action potentials to spread through a network of cells. What is a functional syncytium in the context of cardiac muscle?; A mass of merging cells that function as a unit. How many functional syncytia exist in the heart and where are they located?; Two; one in the atrial walls called the atrial syncytium, and one in the ventricular walls called the ventricular syncytium. What is the cardiac conduction system?; A group of clumps and strands of specialized cardiac muscle tissue that initiates and distributes impulses throughout the myocardium. What is the function of the cardiac conduction system?; It coordinates the events of the cardiac cycle. What is the role of the SA (Sinoatrial) Node in the cardiac conduction system?; It acts as the pacemaker and initiates rhythmic contractions of the heart. What is the function of the Internodal Atrial Muscle?; It conducts impulses from the SA node to the atria. What do the Junctional Fibers do in the cardiac conduction system?; They conduct impulses from the SA node to the AV node. What is the role of the AV (Atrioventricular) Node?; It conducts impulses to the AV Bundle and delays the impulse so that the atria finish contracting before the ventricles contract. What is the function of the AV (Atrioventricular) Bundle (of His)?; It conducts impulses rapidly between the SA node and the bundle branches. What is the purpose of the Left and Right Bundle Branches?; They split off from the AV bundle and conduct impulses to the Purkinje fibers on both sides of the heart. What do the Purkinje Fibers do in the cardiac conduction system?; They are large fibers that conduct impulses to the ventricular myocardium. What is the primary function of the cardiac conduction system?; To coordinate the contraction of the heart muscle. What happens when Purkinje fibers stimulate muscle cells in the ventricles?; The ventricles contract with a twisting motion. What is the role of whorled networks of muscle in the walls of the ventricles?; They help the ventricles contract with a twisting motion when stimulated by Purkinje fibers. What is an electrocardiogram (ECG or EKG)?; A recording of electrical changes that occur in the myocardium during the cardiac cycle. What is the purpose of an electrocardiogram?; To assess the heart’s ability to conduct impulses. What does the P wave in a normal ECG represent?; Atrial depolarization; occurs just prior to atrial contraction. What does the QRS complex in a normal ECG represent?; Ventricular depolarization; occurs just prior to ventricular contraction. What does the T wave in a normal ECG represent?; Ventricular repolarization; occurs just prior to ventricular relaxation. Why is the record of atrial repolarization not visible in a normal ECG?; It is 'hidden' in the large QRS complex since ventricular depolarization is a much larger event. What node normally controls the heart rate?; The SA node. What fibers modify the heart rate in response to changing conditions?; Sympathetic and parasympathetic fibers. Name some conditions that can influence heart rate.; Physical exercise, body temperature, fight-or-flight response, and concentration of ions such as K+ and Ca2+. How do parasympathetic impulses affect heart rate?; Parasympathetic impulses via vagus nerves decrease heart rate by influencing the SA and AV nodes. How do sympathetic impulses affect heart rate?; Sympathetic impulses via accelerator nerves increase heart rate by influencing the SA and AV nodes, and the ventricular myocardium. Where do baroreceptor reflexes arise from?; From the cardiac control center in the medulla oblongata. What is the role of the cardiac control center?; It regulates autonomic impulses to the heart, balancing inhibitory and excitatory effects of parasympathetic and sympathetic fibers. What is the function of the baroreceptor reflex?; To regulate blood pressure by altering heart action. Which type of impulses alter heart action in the baroreceptor reflex?; Autonomic impulses. What type of reflex is the baroreceptor reflex?; A general reflex arc. What are arrhythmias?; Altered heart rhythms. What is fibrillation?; Uncoordinated, chaotic contraction of small areas of myocardium. Is atrial fibrillation life-threatening?; No, atrial fibrillation is not life-threatening, but ventricular fibrillation is often fatal. What is tachycardia?; Abnormally fast heartbeat, greater than 100 beats per minute at rest. What is bradycardia?; Abnormally slow heartbeat, less than 60 beats per minute at rest. What is a flutter in the context of heart rhythms?; Rapid, regular contraction of a heart chamber, 250-350 beats per minute. What is a premature beat?; A beat that occurs before expected in the normal cardiac cycle, often originating from ectopic regions of the heart. What is an ectopic pacemaker?; When damage to the SA node leads to the AV node taking over as a secondary pacemaker, with a rate of 40-60 beats per minute instead of 70-80. What is an artificial pacemaker?; A device used to treat disorders of the cardiac conduction system, implantable and battery-powered. What are blood vessels?; Organs of the cardiovascular system. What do blood vessels form?; A closed circuit, transporting blood from the heart to body cells (or lungs) and back to the heart. What is the function of arteries?; To carry blood away from the ventricles of the heart. What is the role of arterioles?; To receive blood from the arteries and carry it to the capillaries. What occurs at the capillaries?; Exchange of substances between the blood and the body cells. What is the function of venules?; To receive blood from the capillaries and conduct it to veins. What is the function of veins?; To receive blood from venules and carry it back to the atria of the heart. What is angiogenesis?; Formation of new blood vessels. What mainly controls angiogenesis?; Vascular Endothelial Growth Factor (VEGF). Why is angiogenesis regulated in the body?; Because excess, deficient, or inappropriate blood vessel formation can cause common diseases. How does the body promote angiogenesis in response to a blocked coronary artery?; The body secretes VEGF. What can be done if the body's secretion of VEGF is not sufficient to promote angiogenesis?; VEGF may be delivered in time-release capsules. Why do tumors secrete VEGF?; To nourish themselves. What are antiangiogenesis drugs used to treat?; Cancer and age-related macular degeneration. What are the three layers or tunics of arteries?; Tunica interna (intima), tunica media, and tunica externa (adventitia). What is the innermost layer of an artery called?; Tunica interna (intima). What is the middle layer of an artery composed of?; Smooth muscle and elastic tissue. What is the outer layer of an artery called and what is it made of?; Tunica externa (adventitia), made of connective tissue. How do the walls of arteries compare to the walls of veins?; The walls of arteries are thicker and stronger than the walls of veins. What is the function of arteries in terms of blood pressure?; Arteries transport blood under high blood pressure. What do arteries give rise to?; Arteries give rise to smaller arterioles. How do the walls of arterioles compare to those of arteries?; Arterioles have thinner walls than arteries. How many layers or tunics do arterioles have?; Arterioles have the same 3 layers or tunics as arteries. What happens to the walls of arterioles as they become smaller?; The walls of the middle and outer layers become thinner. What functions can both arteries and arterioles perform?; Both can undergo vasoconstriction and vasodilation. What do small arterioles contain in their walls?; A few muscle fibers. What are capillaries?; Capillaries are the smallest-diameter blood vessels. What do capillaries connect?; Capillaries connect the smallest arterioles and the smallest venules. What are capillaries extensions of?; Capillaries are extensions of the inner lining of arterioles. What do the walls of capillaries consist of?; The walls of capillaries consist of endothelium (simple squamous epithelium) only. Are capillaries permeable?; Capillaries are semi-permeable. How is capillary blood flow regulated?; Capillary blood flow is regulated mainly by precapillary sphincters. What are precapillary sphincters?; Precapillary sphincters are smooth muscle surrounding capillaries when they branch off arterioles or metarterioles. How are substances exchanged in capillaries?; By diffusion. Where are the thin slits in capillary walls found?; Where endothelial cells overlap. Do the sizes of openings in capillary walls vary?; Yes, the sizes of openings vary among tissues. What determines the permeability of capillaries?; The size of the slits. How does the metabolic rate of a tissue affect its capillary network density?; Higher metabolic rate results in denser capillary networks. Which types of tissues have a rich capillary supply?; Muscle and nerve tissues. Why do muscle and nerve tissues have a rich capillary supply?; Because they use a large amount of O2 and nutrients. What is the capillary density like in tissues with a lower metabolic rate?; They have fewer capillaries. Can you give an example of a tissue with a lower metabolic rate and fewer capillaries?; Cartilage. What do capillaries exchange between blood and tissue?; Gases, nutrients, and metabolic byproducts. What is the most important method of transfer in capillary exchange?; Diffusion. How do lipid-soluble substances diffuse in capillary exchange?; Through the cell membrane. How do water-soluble substances diffuse in capillary exchange?; Through membrane channels and slits. What forces molecules through the membrane during filtration in capillary exchange?; Hydrostatic pressure. From where is the pressure derived that forces molecules through the membrane during filtration?; Ventricular contraction. What creates osmotic pressure inside capillaries?; The presence of impermeant solute, such as plasma proteins. What does osmotic pressure do in capillary exchange?; It draws water into capillaries, opposing filtration. What happens at the arteriolar end of a capillary during capillary exchange?; H2O and other substances leave the capillary because hydrostatic pressure is greater than osmotic pressure. Why do H2O and other substances leave the capillary at the arteriolar end?; Because hydrostatic pressure is greater than osmotic pressure. What occurs at the venular end of a capillary during capillary exchange?; H2O enters the capillary because osmotic pressure is greater than hydrostatic pressure. Why does H2O enter the capillary at the venular end?; Because osmotic pressure is greater than hydrostatic pressure. What is the function of venules?; Venules transport blood from the capillaries to veins. How do the walls of venules compare to those of arterioles?; Venules have thinner walls and less smooth muscle than arterioles. How do the walls of veins compare to those of arteries?; Veins have thinner walls than arteries. How many layers or tunics do veins have?; Veins have 3 layers or tunics. How is the tunica media of veins different from that of arteries?; The tunica media is less developed in veins. Under what pressure do veins carry blood?; Veins carry blood under relatively low pressure. What is one of the functions of veins besides transporting blood?; Veins function as blood reservoirs. What special feature do many veins have to aid blood flow?; Many veins have flap-like valves. What proportion of blood is in veins and venules at any time?; About 2/3 of blood. What are the three layers of an artery wall?; An endothelial lining, a middle layer of smooth muscle and elastic connective tissue, and an outer layer of connective tissue. What is the function of an artery?; Carries blood under relatively high pressure from the heart to arterioles. How does the wall of an arteriole compare to that of an artery?; An arteriole has a thinner wall with three layers; smaller arterioles have an endothelial lining, some smooth muscle tissue, and a small amount of connective tissue. What is the function of an arteriole?; Connects an artery to a capillary and helps control the blood flow into a capillary by vasoconstricting or vasodilating. What is the structure of a capillary wall?; A single layer of squamous epithelium. What is the function of a capillary?; Allows nutrients, gases, and wastes to be exchanged between the blood and tissue fluid. How does the wall of a venule compare to that of an arteriole?; A venule has a thinner wall and less smooth muscle and elastic connective tissue. What is the function of a venule?; Connects a capillary to a vein. How does the wall of a vein compare to that of an artery?; A vein has a thinner wall with similar layers, but the middle layer is more poorly developed; some veins have flap-like valves. What is the function of a vein?; Carries blood under relatively low pressure from a venule to the heart; valves prevent a backflow of blood and it serves as a blood reservoir. What is atherosclerosis?; Deposits of cholesterol plaque form in the inner lining of walls of arteries. What causes an aneurysm?; A bulge in the wall of an artery formed when blood pressure dilates a weakened area of the vessel; it can burst the wall of the artery. What is phlebitis?; Inflammation of a vein; a common disorder. What are varicose veins?; Abnormal and irregular dilations in superficial veins, most common in the legs. What is blood pressure?; The force the blood exerts against the inner walls of the blood vessels. What role does blood pressure play in the circulatory system?; It circulates the blood. To which part of the circulatory system does the term 'blood pressure' most commonly refer?; Pressure in systemic arteries. Is there blood pressure throughout the entire vascular system?; Yes, there is blood pressure throughout the vascular system. How does blood move throughout the circulatory system?; Blood moves from higher to lower pressure throughout the system. When does arterial blood pressure rise?; When the ventricles contract. When does arterial blood pressure fall?; When the ventricles relax. What is systolic pressure (SP)?; The maximum pressure reached during ventricular contraction. What is diastolic pressure (DP)?; The minimum pressure remaining before the next ventricular contraction. What is pulse pressure (PP)?; The difference between systolic and diastolic blood pressures (SP - DP). What is mean arterial pressure (MAP)?; The average pressure in the arterial system; represents the average force driving blood to the tissues. How is mean arterial pressure (MAP) calculated?; MAP = DP + 1/3(PP). How is blood pressure typically stated?; As a fraction, such as 120/80. In what units is blood pressure measured?; mm Hg. What device is typically used to measure arterial blood pressure?; A sphygmomanometer. How does blood pressure change as the distance from the left ventricle increases?; Blood pressure decreases. What is the purpose of Figure 15.33 in the McGraw-Hill Education text?; To show the sites for measuring arterial pulse. What does Figure 15.33 illustrate?; The sites at which the pulse is most easily detected. What is stroke volume (SV)?; The volume of blood that enters the arteries with each ventricular contraction (~70 mL/beat). What is cardiac output (CO)?; The volume of blood discharged from a ventricle each minute. How is cardiac output (CO) calculated?; Cardiac output = Stroke volume × Heart rate (CO = SV × HR). What is the cardiac output if the stroke volume is 70 mL/beat and the heart rate is 72 beats/min?; 5,040 mL/min. How does blood pressure vary with cardiac output?; Blood pressure increases with an increase in cardiac output. What happens to blood pressure if stroke volume (SV) or heart rate (HR) increases?; An increase in SV or HR causes an increase in cardiac output (CO), which increases blood pressure (BP). What constitutes blood volume?; The sum of volumes of plasma and formed elements. What factors cause variation in blood volume?; Age, body size, and gender. What is the usual blood volume for adults?; About 5 liters, with 4 to 5 liters in females and 5 to 6 liters in males. What percentage of body weight does blood volume constitute?; 8% of body weight. How is blood pressure related to blood volume?; Blood pressure is directly proportional to blood volume. What happens to blood pressure if blood volume decreases?; Blood pressure decreases. What is an example of a condition that decreases blood volume and thus blood pressure?; Hemorrhage. What is Peripheral Resistance (PR)?; The force of friction between blood and the walls of blood vessels. What must blood pressure overcome in order to flow?; Peripheral Resistance (PR). What happens to blood pressure when factors change PR?; Blood pressure also changes. How does vasoconstriction of arterioles affect PR and blood pressure?; Vasoconstriction of arterioles increases PR, which increases blood pressure. What occurs when blood is pumped out of the ventricles?; Arteries swell; rapid elastic recoil sends the blood through the arteries, against PR in arterioles and capillaries. What is viscosity?; The difficulty with which molecules of fluid flow past each other. How does viscosity affect blood flow?; Greater viscosity increases resistance to blood flow. What increases the viscosity of blood?; Blood cells and plasma proteins. What happens to blood pressure when the resistance to blood flow increases?; Greater resistance to flow requires greater force to transport the blood, which increases blood pressure. How does altering the concentration of blood cells or plasma proteins affect blood viscosity?; Any factor that alters the concentration of blood cells or plasma proteins also alters blood viscosity. How does anemia affect blood viscosity and blood pressure?; Anemia lowers the concentration of blood cells, which lowers blood viscosity and thus lowers blood pressure. What determines blood pressure (BP)?; Cardiac output (CO) and peripheral resistance (PR). What is the formula for blood pressure?; BP = CO × PR What is required to maintain blood pressure?; Regulation of cardiac output (CO) and peripheral resistance (PR). What is hypertension?; Long-lasting elevated arterial blood pressure. What are some known causes of hypertension?; Increased Na intake, psychological stress, obesity, and kidney disease. Why is hypertension often referred to as the 'silent killer'?; Because it may not cause any direct symptoms. How does hypertension contribute to atherosclerosis?; By causing long-lasting elevated arterial blood pressure. What serious conditions can hypertension lead to?; Coronary thrombosis, embolism, cerebral thrombosis, embolism, hemorrhage, transient ischemic attack (TIA), and cerebral vascular accident (CVA). What are some prevention methods for hypertension?; Healthy diet and weight, regular exercise, and limiting Na intake. What treatments are available for hypertension?; Diuretics and sympathetic inhibitors. What happens to blood pressure as it moves through the arterial system into the capillary network?; Blood pressure decreases. How much pressure remains at the venous ends of the capillaries?; Little pressure remains. Is venous blood flow solely a direct result of heart action?; No, it is only partly a direct result of heart action. What are the factors that venous blood flow depends on?; Skeletal muscle contraction, breathing movements, and vasoconstriction of veins. How does skeletal muscle contraction affect venous blood flow?; It helps in the movement of blood through the veins. How do breathing movements influence venous blood flow?; Breathing movements assist in the return of blood to the heart. What role does vasoconstriction of veins play in venous blood flow?; Vasoconstriction of veins helps propel blood back to the heart. Where do all veins, except those returning from the lungs, drain?; Into the right atrium. What is the pressure in the right atrium called?; Central venous pressure. What factors influence central venous pressure?; Factors that alter the flow of blood into the right atrium. What does central venous pressure affect?; Pressure within the peripheral veins. What happens to central venous pressure when the heart beats weakly?; It increases. What is the result of an increase in central venous pressure?; Blood backs up into the peripheral veins. What condition can be caused by blood backing up into peripheral veins?; Peripheral edema. What increases blood flow to the right atrium and central venous pressure?; An increase in blood volume or venoconstriction. What are the benefits of regular aerobic exercise on the cardiovascular system?; Increased pumping efficiency, blood volume, hemoglobin concentration, and number of mitochondria. By how much can the heart enlarge due to regular aerobic exercise?; 40% or more. What happens to stroke volume as a result of regular aerobic exercise?; Stroke volume increases. How do heart rate and blood pressure change with regular aerobic exercise?; Heart rate and blood pressure decrease. To benefit the cardiovascular system, to what percentage of the maximum should the heart rate increase during exercise?; 70 to 85% of maximum (220 − your age). How long should each exercise session last to benefit the cardiovascular system?; 30 to 60 minutes. How often should you exercise each week to benefit the cardiovascular system?; At least 3 to 4 times per week. What are the two pathways that blood vessels form?; The pulmonary circuit and the systemic circuit. What circuit is responsible for carrying blood between the heart and the lungs?; The pulmonary circuit. What circuit is responsible for carrying blood between the heart and the rest of the body?; The systemic circuit. What is the path of blood flow in the pulmonary circuit starting from the right ventricle?; Right ventricle → pulmonary trunk → right and left pulmonary arteries → lobar branches, repeated divisions → pulmonary arterioles → pulmonary capillaries → pulmonary venules and veins → left atrium. What is the oxygen and carbon dioxide content in the blood of pulmonary arteries and arterioles?; Low in O2 and high in CO2. Where does gas exchange occur in the pulmonary circuit?; In the pulmonary (alveolar) capillaries. What is the oxygen and carbon dioxide content in the blood of pulmonary venules and veins?; Rich in O2 and low in CO2. Where does oxygen-rich blood move from and to in the systemic circuit?; From the left atrium to the left ventricle. What happens when the left ventricle contracts?; It sends blood into the systemic circuit. What is the path of blood flow in the systemic circuit starting from the left ventricle?; Left ventricle → aorta → all arteries and arterioles leading to body tissues → systemic capillaries → systemic venules and veins → right atrium. What effect does high osmotic pressure in interstitial fluid have on alveoli?; It draws water out of alveoli. What is the largest artery in the body?; The aorta. What does the aorta supply blood to?; All of the systemic arteries. What organs are supplied by the right and left coronary arteries from the ascending aorta?; The heart. What does the celiac artery from the abdominal aorta supply?; Organs of the upper digestive tract. Which artery supplies the right upper limb and right side of the head?; The brachiocephalic trunk from the arch of aorta. What does the phrenic artery supply?; The diaphragm. Which artery supplies the left side of the head?; The left common carotid artery from the arch of aorta. What organs are supplied by the superior mesenteric artery?; Portions of the small and large intestines. What does the left subclavian artery supply?; The left upper limb. Which artery supplies the adrenal gland?; The suprarenal artery from the abdominal aorta. What does the renal artery supply?; The kidney. Which artery supplies the bronchi?; The bronchial artery from the thoracic aorta. What organs are supplied by the gonadal artery?; The ovary or testis. What does the pericardial artery supply?; The pericardium. Which artery supplies the lower portions of the large intestine?; The inferior mesenteric artery. What does the esophageal artery supply?; The esophagus. Which artery supplies the posterior abdominal wall?; The lumbar artery. What does the mediastinal artery supply?; The mediastinum. Which artery supplies the sacrum and coccyx?; The middle sacral artery. What does the posterior intercostal artery supply?; The thoracic wall. Which artery supplies the lower abdominal wall, pelvic organs, and lower limb?; The common iliac artery. Which arteries supply blood to the brain, head, and neck?; Branches of the subclavian and common carotid arteries. What does the cerebral arterial circle (circle of Willis) join?; The carotid and vertebral artery systems. What is the function of the arteries connected by the cerebral arterial circle?; They supply blood to the brain. What is the benefit of the arrangement of the cerebral arterial circle?; It provides alternate pathways for blood to reach the brain. From where do the cerebral arteries emerge to supply blood to brain tissues?; From the cerebral arterial circle (circle of Willis). What does the subclavian artery do in the neck?; It gives off branches. Where does the subclavian artery continue after giving off branches in the neck?; Into the arm. Which arteries supply blood to the thoracic wall?; Branches of the subclavian artery and the thoracic aorta. What does the abdominal aorta divide into?; The common iliac arteries. What regions do the common iliac arteries supply blood to?; The pelvic organs, gluteal region, and lower limbs. Into what arteries does the common iliac artery divide?; The internal iliac artery and external iliac artery. Which areas does the internal iliac artery supply blood to?; The pelvic and gluteal areas. What arteries provide the major blood supply to the lower limbs?; The external iliac arteries. What does systemic venous circulation do?; It returns blood to the heart after the exchange of gases, nutrients, and wastes between blood and cells. How do vessels of the venous system originate?; From the merging of capillaries into venules, venules into small veins, and small veins into larger ones. Why are venous pathways difficult to follow compared to arterial pathways?; Due to irregular networks and unnamed tributaries. What do the pathways of larger veins usually parallel?; They usually parallel arteries of the same name. Where do all systemic veins converge?; Into the superior and inferior venae cavae. Through which part of the heart do systemic veins return blood?; Through the right atrium. What do the external jugular veins drain blood from?; The face, scalp, and superficial neck. What do the internal jugular veins drain blood from?; The brain, and deep portions of the face and neck. What are the two systems of veins that drain the upper limb and shoulder?; Deep set of veins and superficial set of veins. What is the flow of blood in the deep set of veins from the upper limb and shoulder?; Digital veins → radial and ulnar veins → brachial veins. What is the flow of blood in the superficial set of veins from the upper limb and shoulder?; Anastomoses in palm and wrist → basilic and cephalic veins. Which vein does the basilic vein join?; The brachial vein. Which vein does the cephalic vein join?; The axillary vein. Which veins drain the abdominal and thoracic walls?; Tributaries of the brachiocephalic and azygos veins. Into which vein does the azygos vein drain?; The superior vena cava. What is unique about portal veins?; They do not transport blood directly to the heart. What is the name of the venous pathway that drains the abdominal viscera?; The hepatic portal system. Which organs' capillaries drain into the hepatic portal vein?; The stomach, intestines, pancreas, and spleen. Where does the hepatic portal vein transport blood for processing?; To the liver. After processing in the liver, where is the blood delivered?; To the inferior vena cava. What is unique about portal systems like the Hepatic Portal System and the Renal Portal System?; They filter blood through 2 sets of capillaries instead of the usual 1 set. How many sets of capillaries do portal systems filter blood through?; 2 sets of capillaries. What unique function does the second set of capillaries in portal systems perform?; The second set of capillaries performs a unique function in the body. Into what groups do veins from the lower limb and pelvis drain?; Deep and superficial groups of veins. What is the sequence of deep veins from the foot to the external iliac vein?; Veins in foot → anterior and posterior tibial veins → popliteal vein → femoral vein → external iliac vein. What is the sequence of superficial veins from the foot?; Veins in foot → small and great saphenous veins. Which vein is the longest in the body?; The great saphenous vein. What happens to cholesterol in the blood vessels as people age?; Cholesterol deposition increases. What change occurs in coronary arteries with aging?; Coronary arteries become narrowed. How may the heart size change due to aging?; The heart may shrink slightly or enlarge due to disease. What happens to the proportion of the heart consisting of cardiac muscle with aging?; It declines. What increases in the heart as people age?; Fibrous connective tissue and adipose tissue. What changes may occur to the heart valves and left ventricular wall with aging?; They may thicken. What happens to systolic blood pressure with aging?; It increases. What happens to the resting heart rate with aging?; It decreases. What happens to the lumens of large arteries as people age?; They narrow as arterial walls thicken. What happens to arterial elasticity with aging?; It decreases. What factors contribute to cardiovascular disease?; Both environmental and hereditary factors. What is Marfan syndrome?; A connective tissue defect involving an abnormal type of the protein fibrillin. How does Marfan syndrome affect the cardiovascular system?; It can weaken the wall of the aorta, leading to the risk of the aorta bursting and sudden death. What is familial hypertrophic cardiomyopathy?; An inherited condition caused by an abnormal myosin chain in cardiac muscle, leading to overgrowth of the myocardium. What can familial hypertrophic cardiomyopathy result in?; It can result in sudden death. What happens in the inherited deficiency of a mitochondrial enzyme that breaks down fatty acids?; Heart failure results from the inability to break down long-chain fatty acids and use them for energy. Why is the ability to break down long-chain fatty acids important for cardiac muscle?; Cardiac muscle uses long-chain fatty acids as a primary energy source. What is familial hypercholesterolemia?; A condition where abnormal LDL receptors on liver cells do not take up cholesterol from the blood. What are the consequences of familial hypercholesterolemia?; It results in high cholesterol and coronary artery disease. What is Coronary Artery Disease (CAD)?; A disease involving the deposition of cholesterol plaque on the inner walls of coronary arteries. What does Coronary Artery Disease lead to?; Obstruction of coronary arteries and O2 deficiency in cardiac muscle. What conditions are often accompanied by Coronary Artery Disease?; High serum cholesterol and hypertension. What is the chest pain caused by exertion in Coronary Artery Disease called?; Angina pectoris. What major event can Coronary Artery Disease contribute to?; Myocardial infarction (heart attack). What are two treatments for Coronary Artery Disease?; Percutaneous transluminal coronary angioplasty (PTCA) and coronary bypass surgery. Where is the aortic valve best heard?; In the second intercostal space right of the sternum. Where is the pulmonary valve best heard?; In the second intercostal space left of the sternum. Where is the tricuspid valve best heard?; At the fifth intercostal space left of the sternum. Where is the mitral valve best heard?; In the fifth intercostal space on the left at the nipple line. Where can the pulse for the temporal artery be taken?; Anterior to the ear. Where can the pulse for the carotid artery be measured?; In the inferior medial portion of the neck. Where can the pulse for the brachial artery be taken?; In the distal brachial region on the anterior side. Where can the pulse for the radial artery be measured?; On the lateral side of the wrist on the anterior side. Where can the pulse for the femoral artery be taken?; In the inguinal region. Where can the pulse for the popliteal artery be measured?; In the popliteal region. Where can the pulse for the dorsalis pedis artery be taken?; In the anterior ankle. Where can the pulse for the posterior tibia artery be measured?; In the posterior ankle. What are the functions of the organs of the cardiovascular system?; The organs of the cardiovascular system function to transport nutrients, oxygen, and hormones to cells throughout the body and remove metabolic wastes. What are the coverings of the heart?; The coverings of the heart include the pericardium, which consists of the fibrous pericardium and the serous pericardium. What are the layers that compose the wall of the heart?; The heart wall is composed of three layers: the epicardium (outer layer), myocardium (middle layer), and endocardium (inner layer). Can you identify and locate the major parts of the heart?; The major parts of the heart include the atria (upper chambers), ventricles (lower chambers), valves (tricuspid, pulmonary, mitral, and aortic), and major blood vessels (aorta, superior and inferior vena cava, pulmonary arteries, and veins). What is the function of each part of the heart?; The atria receive blood returning to the heart, the ventricles pump blood out of the heart, the valves prevent backflow of blood, and the major blood vessels transport blood to and from the heart. Can you trace the pathway of blood through the heart?; Blood flows from the body into the right atrium, through the tricuspid valve to the right ventricle, through the pulmonary valve to the pulmonary arteries, to the lungs, back through the pulmonary veins to the left atrium, through the mitral valve to the left ventricle, and then through the aortic valve to the aorta and out to the body. What is coronary circulation?; Coronary circulation refers to the movement of blood through the vessels that supply the heart muscle (myocardium) with oxygen and nutrients. What is the cardiac cycle?; The cardiac cycle is the sequence of events that occur with each heartbeat, including systole (contraction) and diastole (relaxation) of the atria and ventricles. How are heart sounds produced?; Heart sounds are produced by the closing of the heart valves: the 'lub' sound is caused by the closure of the atrioventricular valves, and the 'dub' sound is caused by the closure of the semilunar valves. What are the parts of a normal ECG pattern?; The parts of a normal ECG pattern include the P wave, QRS complex, and T wave. What is the significance of a normal ECG pattern?; A normal ECG pattern indicates the electrical activity of the heart and helps in diagnosing various cardiac conditions. How is the cardiac cycle controlled?; The cardiac cycle is controlled by the sinoatrial (SA) node, atrioventricular (AV) node, and the autonomic nervous system. What are the major types of blood vessels?; The major types of blood vessels are arteries, veins, and capillaries. How do the structures of the major types of blood vessels differ?; Arteries have thick, elastic walls to handle high pressure; veins have thinner walls with valves to prevent backflow; capillaries are thin-walled to allow exchange of substances. How are substances exchanged between blood in capillaries and the tissue fluid surrounding body cells?; Substances are exchanged through diffusion, filtration, and osmosis across the thin walls of capillaries. How is blood pressure produced?; Blood pressure is produced by the force of the heart pumping blood through the arteries and the resistance of the arterial walls. How is blood pressure controlled?; Blood pressure is controlled by the autonomic nervous system, hormones, and the kidneys. What mechanisms aid in returning venous blood to the heart?; Mechanisms include the skeletal muscle pump, respiratory pump, and valves in veins. What are the two main circuits of the cardiovascular system?; Pulmonary and systemic circuits. What is the function of the pulmonary circuit?; To carry blood from the heart to the lungs and back to the heart. What is the function of the systemic circuit?; To carry blood from the heart to the rest of the body and back to the heart. What are the major arteries in the human body?; Aorta, carotid arteries, subclavian arteries, renal arteries, and femoral arteries. What are the major veins in the human body?; Superior vena cava, inferior vena cava, jugular veins, subclavian veins, and femoral veins. What are some common changes in the cardiovascular system with aging?; Thickening of the arterial walls, decreased elasticity of blood vessels, reduced cardiac output, and increased blood pressure. How does the elasticity of blood vessels change with age?; The elasticity decreases, making the vessels stiffer. What impact does aging have on cardiac output?; Cardiac output generally decreases with age.