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Human Physiology Lecture Unit 3 Exam Study Guide Chapter 14: Cardiovascular Physiology Review the anatomy of the heart. It will help you understand the physiology. Read through and understand pages 436 – 440, Pressure, Volume, Flow, and Resistance What is a pressure gradient and how does it a...
Human Physiology Lecture Unit 3 Exam Study Guide Chapter 14: Cardiovascular Physiology Review the anatomy of the heart. It will help you understand the physiology. Read through and understand pages 436 – 440, Pressure, Volume, Flow, and Resistance What is a pressure gradient and how does it affect flow? A pressure gradient is the difference in amount of pressure between two areas. Flow is directly related to the pressure gradient so if there is an increase in pressure gradient there is an increase in flow rate How does distance affect pressure of a fluid in motion? The longer the distance the more friction there will be, this will cause more resistance. Pressure decreases with resistance How does resistance affect flow? Resistance opposes flow so if resistance is increased flow is decreased How does viscosity affect resistance and flow? Increased viscosity then increased resistance , increased viscosity then decrease in flow How does the vessel radius affect resistance and flow? The radius is the main factor for flow, the bigger the radius the less resistance and more flow and vice versa i. Vasoconstriction/vasodilation? Vasodilation decreases resistance and increases flow , vasoconstriction increases resistance and decreases flow f. What is the difference between flow rate and velocity? Flow rate is the volume that passes in time and velocity is the speed per time What is the relationship between flow rate and velocity? Velocity and flow rate are directly related What is the relationship between velocity and the cross-sectional area of the tube? It is inversely related What is Poiseuille’s Law? All about resistance. What increases resistance and decreases and what opposes flow. What is the difference between the autorhythmic and contractile cells? Autorhythmic generate action potentials and make up less than 2 % of the cells in the heart. Contractile cells are cells that contract and make up 98% of the cells in the heart How does the contractile cardiac cell contract? Action potential enters from adjacent cells into the t tubule, calcium voltage channels open and calcium enters the cell, calcium release through ryr channels, this causes a calcium spark, creates calcium signal and then calcium binds to troponin to initiate contraction, relaxation occurs when calcium unbinds from troponin. Calcium is pumped back into the sarcoplasmic reticulum for storage. Calcium is also exchanged between the icf and the ecf via the NCX. the ncx is an antiport in the sarcolemma. 3 sodium ions from the ecf are exchanged for a calcium ion from the icf Pages 446 – 448 and figure 14.10 Understand the steps Know the steps of an action potential of a cardiac contractile cell rmp starts at -90mV and there is no threshold. Ap comes from the autorhythmic cells. Sodium voltage gates open at depolarization and sodium voltage gates close at max depolarization (20mV) repolarization starts at depolarization and fast potassium gates close then the calcium voltage gates open and creates a plateau , calcium voltage gates close and slow potassium gates open then repolarization resumes Page 449 and figure 14.11 Know the membrane potential, threshold, when the gates are opened and closed, etc rmp is -90 and there is no threshold. The sodium voltage gates open at depolarization, at max depolarization the sodium voltage gates close, repolarization calcium open fast potassium is closed but slow potassium is open What is the plateau and why is there one? A plateau is when fast potassium voltage gates close and the calcium voltage gate opens. This allows time for the calcium to bind to troponin and prevents tetanus Compare refractory times between cardiac contractile cells and skeletal muscle cells. Cardiac refractory period is longer than skeletal muscle and this is due to plateau and there is no tetanus i. Why is that important? Allows for a complete contractile cell to contract and relax Know the steps of an action potential in a cardiac autorhythmic cell there is no rmp and hovers around -60 mV. (this is called pacemaker potential) If the channel is open it opens to sodium and there is an influx of sodium into the cell. Threshold is at -40 mV and the calcium channels open and cause depolarization. The calcium voltage gates will time out and there is no set max depolarization. The potassium voltage gates open for repolarization and there is no hyperpolarization Pages 450 – 451 and figure 14.13 Know the pacemaker potential, what gates are involved and when they open/close, threshold, etc. there is no rmp instead it is called the pacemaker potential and it hovers around -60 mV. If the channel opens it opens to sodium at -60 mV threshold is at -40 mV and calcium channels open and sodium closes. At depolarization the ca voltage gate closes and there is no set max depolarization. K voltage is open at repolarization Table 14.3, page 452, compares the difference between action potentials of skeletal muscle, cardiac contractile cells, and cardiac autorhythmic cells. The conducting system of the heart: See figure 14.15. Know the steps. This will mean you will need to know the anatomy of the cardiac conduction system. Sa node depolarizes and electrical activity goes rapidly to av node through internodal pathways. Depolarization spreads slowly across the atria and conduction slows through the av node. Depolarization moves rapidly through the ventricular conduction system to the apex of the heart. Depolarization wave spreads upward from the apex i. AV node located in the lower right atrium at introventricular septum and contracts ventricles, SA node is located in the upper right atrium is also called the pacemaker and sets overall hr , AV bundle is located at the upper interventricular septum , internodal pathway is located at the atrial wall 10.Know the waves of the ECG and what they represent. P wave - represents atrial depolarization and leads to atrial contraction. Qrs complex represents ventricular depolarization and leads to ventricular contraction. T wave represents ventricular repolarization and leads to ventricular filling a. Page 455 and figure 14.16f 11.Know the correlation between an ECG and electrical events in the heart a. Page 458, figure 14.17 12.Know the mechanical events of the cardiac cycle 1. Atrial filling. The av valves are open(when martial pressure is higher than ventricular pressure) and ventricles are filling. 80% of this is done passively. 2. Atrial systole . the atria contracts driving the last 20% of blood into the ventricles. 3. Ventricular systole . the av valves close and there is vibrations following closure.vrntricular isovolumic contraction occurs The atria relaxes and blood flows into the atria. Edv occurs 4. Ventricular ejection . slv open and blood is ejected into the arteries. 5. Ventricular relaxation. Arterial blood flows back towards the heart and the slv shut. Ventricular muscles relax and pressure drops. No blood enters or exits.isovolumic ventricular diastole occurs Av valves open when ventricular pressure drops below atrial pressure. Esv and isovolumic ventricular relaxation occurs 13.Pages 459 – 461 and figure 14.18 (a and b) Pay attention to what happens during atrial/ventricular diastole/systole, isovolumic contraction/relaxation, etc. atrial diastole is filling. Ventricular diastole is filling. Atrial systole is contraction and ventricular systole is contraction. Isovolumic contraction when all the heart valves are closed isovolumic relaxation all the heart valves are closed. Edv is end diastolic volume this is the volume in the blood after ventricular diastole (filling) When do the valves open and close? The av valve opens during atrial filling. The slv valve is open during late ventricular systole 14.What is stroke volume? The amount of blood ejected from the ventricle in one heartbeat a. How is it calculated? Edv - esv 15.What is cardiac output? Amount of blood ejected per min from the ventricle a. How is it calculated? Sv x hr 16.Compare/contrast ANS control of the heart rate parasympathetic decreases the heart rate by hyperpolarizing the pacemaker. It opens potassium channels and closes calcium. Sympathetic increases heart rate by depolarizing the membrane. Open calcium and sodium channels a. Figure 14.20, page 465 16.What are the different factors that influence stroke volume? Contractility, venous return, frank starling law of the heart, Pages 466 – 470 Length-tension relationship? Determined by the volume of blood at the begging of a contraction. Degree of stretch is called Preload - the amount of blood in the ventricle before contracting Frank-Starling Law of the Heart - amount of blood entering the heart is the same amount that is ejected. Stroke volume is directly proportional to the edv 17.What are inotropic effects? They are anything that affects contractility. Negative means it decreases contractility and positive inotrope means it increases the contractility How do they influence stroke volume? Contractility is directly proportional stroke volume. They increase calcium availability by opening calcium channels and this increases the calcium concentration gradient. Figure 14.22 18.What are the factors that affect venous return to the heart? Skeletal muscle pump, respiratory pump, and sympathetic nervous system. Chapter 15: Blood Flow and Transport Review the anatomy of the blood vessels. Artery - blood vessel, conducts blood away from the heart. Aka pressure reservoirs. Conduct blood at the highest pressure and have the most elastic content Ateriols- smaller arteries aka variable pressure vessels and made of mostly smooth muscle. Met arteriole - located at the center of the capillary bed and controls the blood flow into cap bed. Cappillaries - are the smallest and thinnest exchange vessels. Pericytes - cells around capillaries also control exchange. Venules - small veins veins can do some exchange but much veins- conduct blood at the lowest pressure to the heart. Aka volume reservoirs. Mostly made of tunica externa and have large lumes. 60% of total blood circulation are found in systemic veins Understand figure 15.1, page 477 figure 15.1 is showing that each side of the heart works independently. Compare the structures of the 5 different blood vessels, figure 15.2 artery have the most elastic content. Arteriols are mostly smooth muscle ans still elastic but not as much as an artery. Capillaries are made from endothelium. Venules are made of endothelium and fibrous tissue and veins are mostly tunica externa and are slightly elastic What are metarterioles, precapillary sphincters, and pericytes? Pericytes are the cells around capillaries, metarterioles are located in the center of every capillary bed and precapillary sphincters open and close to direct blood flow to capillaries or venous circulation Blood pressure: Pages 481 – 485 *Table 15.1* says that blood flows if a pressure gradient is present and blood flows from areas of higher pressure to lower pressure. Blood flow is opposed by resistance of the system and the three factors that oppose blood flow is radius and length of the blood vessels and viscosity of the blood What is systolic pressure and diastolic pressure? Systolic blood pressure is the working pressure. It is the pressure that is exerted onto the arterial walls during ventricular contraction. diastolic pressure is the resting pressure. The pressure that is being exerted on wall during ventricular filling. What is pulse and pulse pressure? Pulse is feeling pressure of the heart beat in specific areas. Pulse pressure is used to figure out the map of a blood pressure What is MAP?mean arterial pressure. The average arterial pressure and the driving force of blood MAP = diastolic pressure + ⅓ pulse pressure How does cardiac output and peripheral resistance affect MAP? If co is increased then the map is increased if resistance is increased then the map increases How do changes in blood volume affect blood pressure?if blood volume increases then resistance increases and map increases What factors influence MAP? See figure 15.8b, page 485 fluid intake and losee, heart rate, stroke volume, diameter of the arterioles or veins What are the compensation mechanisms for increased blood volume? Decrease co which decreases the stroke volume or heart rate, decrease resistance by using vasodilation, renal system can increase urine production which gets rid of excess fluid and decrease blood volume Page 486, figure 15.9 fast response is done by the cardiovascular system and it causes vasodilation and decreased cardiac output which makes the blood pressure normal. The slow response is done by the kidneys and it excretes fluid out in the urine deceases blood volume and makes blood pressure normal What is myogenic autoregulation? Smooth muscle has calcium mechanical gates in the cell membrane. When the smooth muscle stretches calcium mechanical gates open and there is an influx of calcium to bind to troponin which causes the filament to slide and stretch Compare mechanisms of active and reactive hyperemia. Hyperemia increase in blood flow to the tissues due to a metabolic need, active hyperemia increase in blood flow reacting to blood occlusion How does the sympathetic branch control most vascular smooth muscle? By tonic control. If the sympathetic nervous system increases the frequency of action potentials to the vessel it causes vasoconstriction if the sympathetic nervous system decreases the frequency of ap to the vessel it dilates Read page 489 and look at figure 15.11. What is the baroreceptor reflex? What are the steps? It helps maintain blood pressure at a normal level. Baroreceptors allow for information about blood pressure to be sent to the medulla. If the map increases then the baroreceptors will increase the frequency of signals to the cvcc. This will start the process of compensation (decreasing the hror decreasing resistance via vasodilation) if the map decreases then the baroreceptors will decrease the frequency of signals to the cvcc. This will start the process of compensation (incraseing the hr or increasing resistance via vasoconstriction Figure 15.14, pages 492 – 494 Exchange at the capillaries: Know the difference between the 3 kinds of capillaries continuous is the most common and has intercellular clefts. Found in skeletal muscle and skin is the least permeable. Fenestrated capillaries have larger intercellular clefts and have fenestrations. Found in the intestines and kidneys. Sinusoids are the most permeable have the largest intercellular cleft and largest fenestrations. Whole cells are able to pass through the fenestratinos and found in the liver bone marrow and spleen Why is the velocity of blood flow lowest in the capillaries? It is slowest in the capillaries because velocity is inversely proportional to the total cross sectional ar ea and even though capillaries are small they are found all over the body this makes the cross sectional area big and the bigger the area the slower the velocity What are the methods of capillary exchange? Compare them. i. Diffusion, transcytosis using vesicular transport like endocytosis and exocytosis, bulk flow is moving down the concentration gradient,. Paracellular between cells and transcellular through cells filtration in the capillary beds is moving fluid from the plasma through the endothelium and into the tissues and is driven by hydrostatic pressure. Aboroption is the movement of fluid from the tissues to the plasma and it is drive by osmotic pressure d. What is colloid osmotic pressure? How does it affect capillary exchange? It is pressure due to solute and fluids move toward higher osmotic pressure. Osmotic pressure drives absorption. 10.Know figure 15.18.hydrostatic pressure is higher at the arterial end and osmotic pressure is higher than hydrostatic at the venular end. Filtration is prevalent at the arterial end and absorption is prevalent at the venular end Take this picture seriously. I could ask so many questions from this figure. I’m not kidding. 11.What are the functions of the lymphatic system? Drain excess tissue fluid, clean lymph, and transport fats from the intestines What is edema?swelling What are 3 factors that disrupt normal balance between capillary filtration and absorption? High hydrostatic pressure (blood pressure) , decrease in osmotic pressure, tissue osmotic pressure from leaked proteins i. Page 500 Chapter 16: Blood What are the components of plasma? Water (92%) proteins (7%) remaining (1%)- ions, organic molecules, gases, trace elements, vitamins Know the functions of the plasma proteins.albumin- main plasma protein and creates osmotic pressure the largest of plasma proteins globulins generic antibodies it is going to bind to try and destroy any cells it does recognize fibrinogen - inactive protein enzyme, secreted in the inactive form so it doesnt break down our own tissues. When activated it creates a blood clot. Only happens when there is damage to the blood vessel wall. Transferrin - transports iron. Albumin and globulin also transport lipids ( fats) See figure 16.1, page 512. What are the functions of the blood cells? Erythrocytes (RBC) they carrier gasses. Hemoglobin in rbc binds to gases. Platelets also called thrombocytes are used to make a blood clot. Luekocytes are also called white blood cells they either have granules or they do not. Erythrocytes, leukocytes (all 5), and thrombocytes neutrophils - do not stay a specific color they are neutral. They are small phagocytes they digest or engulf small things that do damage to the body ex bacteria . most common white blood cell. Eosinophil red white blood cells. They are granulocytes. They are anti parasitic cells and fight and digest parasites in the blood and body. Also get rid of allergens and their by-products. Basophils - granules that stain dark blue. Also known as mast cells they are the least common if the patient is healthy. They also fight against allergens. They create inflammation and prevent blood from clotting. Basophils/mast cells secrete histamine (causes inflammation) and heparin (anticoagulant). Monocytes - largest of the wbc . they are macrophages, they leave the circulation and become part of your tissues. They use diapedesis? phagocytes . lymphocytes - smallest wbc, antibodies. They become t cells and b cells. What are the 3 cytokines involved in hematopoiesis, and what do they influence?Hematopoiesis is the formation of blood cells that comes from the bone marrow. Cytokines control the production of blood cells. Colony stimulating factor - increase leukopoiesis (formation of white blood cells) thromobipoetin controls formation of thrombocytes erythopoeitin regulates red blood cell productin comes mainly from the kidneys and stimulates bone marrow to make rbc Table 16.1, page 515 What is a CBC? Complete blood count What is it? They take a drop of blood and put it under the microscope and there is a grid and they count the cells and do math and calculate. What are the general normal values (I will cover the specifics in class) Know the steps of hemoglobin metabolism/ synthesis hemoglobin is the protein found in red blood cells that binds to oxygen. One hemoglobin can bind to 4 oxygen. You need iron to make hemoglobin 1. Iron is ingested from the diet 2. Iron absorbed by active transport 3. Transferrin protein transport iron in plasma. (iron can either go to the liver and be stored as ferritin or taken to the bone marrow) 4. Taken to the bone marrow and forms hemoglobin 5. Goes inside of red blood cell 6. Rbc lives for 120 days and then red blood cell goes to the spleen and it breaks down the worn out rbc. 7. Made into bilirubin is changed into bile by the liver and bile is stored in the gallbladder. 8. Can be metabolized in urine or can be excreted into the intestines and metabolizes in the feces Figure 16.6c, page 520 What are the steps of hemostasis? 1. Vasoconstriction 2. Forming a platelet plug 3 then forming a clot Chapter 17: Mechanics of Breathing You will need to know the anatomy of the bronchial tree and lung to understand the physiology. What are the 4 primary functions of the respiratory system? Exchange gases between the atmosphere and the blood, regulation of body pH, protection from inhaled pathogens and irritating substances, vocalization a. Page 533 What is the importance of the pleural sac? It is a double layered membrane around the lungs. The pleural fluid between the layers lubricates the layers to prevent friction and pain. It also keeps the lungs inflated What are the cells of the alveolar sacs? Type one (flat squamous cell) is used for respiration/gas exchange. Type 2 (cuboid cell) secretes surfactant and alveolar macrophage is for immunity What are the parts of the respiratory membrane? Alveolar type 1 cell, basement membrane and this makes pulmonary capillary endothelium What is the pathway of the pulmonary circulation? Right ventricle - pulmonary trunk - pulmonary arteries - pulmonary arteries - pulmonary capillaries pulmonary venules - pulmonary veins - left atrium How does the mucociliary escalator work? It traps pathogens and gets rid of them. The layer of mucous traps the pathogens and the saline layer separates the mucous from the cilia and the cilia moves the mucous towards the oral cavity the pcce will also secrete saline, the cells have a cftr channel that secretes chloride into the lumen and sodium and water will following using a paracellular pathway which makes saline What is Dalton’s law? The sum of partial pressures in a container add up to the total gas pressure What is partial pressure? In a mixture of gasses each gas exerts partial pressure on a container wall What is the mechanism on how gas particles move?fluids move down a concentration gradient 10.What is Boyle’s law and how does it apply to the respiratory system? Changing the volume of a container changes the pressure inside. Volume of a container is inversely proportional to pressure. This means that when the diaphragm is relaxed there is less volume and more pressure when the diaphragm is contracted volume is increases and pressure is decreased 11.Know the lung volumes and capacities (the definitions): TV, IRV, ERV, and RV tidal volume (TV) simple inhale and simple exhale IRV (inspiratory reserve volume) the max amount you can force into the lungs after a normal exhale) ERV (expiratory reserve volume) max amoun of air you can force out of the lungs after exhale RV (residual volume) the volume of air left in the lungs after a forced exhale IC, FRC, TLC, and VC IC (inspiratory capacity) tidal volume + RV FRC (functional residual capacity) ERV + RV. VC (vital capacity) TV + IRV+ERV. TLC (total lung capacity) VC + RV or TV+ IRV+ERV + RV 12.Know the pressure changes in the lungs during quiet breathing intraplueral pressure as we inhale pressure steadily decreases as we exhale pressure steadily increases. Volume of air moved in the lungs steadily increases as we exhale the volume of air in the lungs steadily decreases alveolar pressure as we inhale the pressure inside the alveolus starts to decrease and then halfway through the inhale pressure starts to increase due to the incoming air. During exhale alveolar pressure starts to increase and then half way through the pressure starts to decrease due to air leaving Pages 545 – 548 Figure 17.9 13.What is surfactant and how does it work? It is a detergent that breaks down water polar molecules in alveoli it prevents the alveolar walls from collapsing 14.What factors that affect airway resistance? Increased radius decreases resistance and decreased radius increases resistance. Decreased Air flow increases resistance and increased air flow decreases resistance. Bronchodilaton and bronchoconstriction a. Table 17.2, page 551 15.What is the difference between the total volume of air that enters the airways and the volume of fresh air that reaches the alveoli? Total pulmonary ventilation is the breathing rate x tidal volume and alveolar ventilation is breathing rate x (TV dead air space) Page 551 Figure 17.12b Chapter 18: Gas Exchange and Transport What is hypoxia and hypercapnia? Hypoxia is a decrease in oxygen levels and hypercapnia is an increase in carbon dioxide a. See table 18.1. What are the 3 variables that sensors respond to avoid hypoxia and hypercapnia?o2 levels, co2 levels, and ph Understand figure 18.1, page 563 Understand figure 18.2, page 565 a. Compare the gas partial pressures at each location in the figure. How is the gas diffusion rate affected by: Surface area increase in surface area diffusion is faster Concentration gradient decrease concentration gradient decrease speed of diffusion Barrier permeability decrease membrane permeability decrease diffusion Diffusion distance increase distance decrease diffusion What are the 3 factors that determine the movement of gas molecules from air to liquid? How is oxygen transported in blood? What 2 factors determine the amount of oxygen that binds to hemoglobin? Understand figure 18.9, page 574. All parts. 10.How is carbon dioxide transported? (3 ways)
