ANA 110 Unit 1 Study Guide Key PDF

Unit 1 Study Guide: The Cardiovascular System WEEK 1: Describe the function of the systemic & pulmonary circuits: Systemic Circuit: carries blood to/from the tissues of the body; left side of the heart Pulmonary Circuit: carries blood to/from the lungs; right side of the heart Bonus: Coronary Circui...

Unit 1 Study Guide: The Cardiovascular System WEEK 1: Describe the function of the systemic & pulmonary circuits: Systemic Circuit: carries blood to/from the tissues of the body; left side of the heart Pulmonary Circuit: carries blood to/from the lungs; right side of the heart Bonus: Coronary Circuit: carries blood to/from the heart tissues; left side of the heart Name the body cavity within which the heart is located: Mediastinum Name the protective membranes surrounding the heart & describe their functions: 1. Fibrous Pericardium: made of dense irregular connective tissue; tough outer sac 2. Serous Pericardium: two layers a.​ Parietal (Serous) Pericardium: contact thoracic cavity (most superficial) b.​ Visceral (Serous) Pericardium: contact heart (most deep) Name the structure formed by the fusion of the fibrous & serous pericardium: Pericardial Sac Name the fluid is located between the parietal & visceral pericardium and describe its function: Pericardial Fluid- prevents friction when the heart beats Name the three layers of the heart wall from superficial to deep & briefly describe the function/characteristics of each layer: 1. Epicardium: Contains blood & lymphatic vessels to supply the heart 2. Myocardium: Cardiac Muscle Fibers; nutrients supplied by coronary arteries of the epicardium 3. Endocardium: Lines heart chambers & valves Label the gross anatomy of the anterior & posterior aspects of the heart: Label Each Chamber/Vessel of the heart: Name the three structures that return blood to the right atrium: IVC, SVC & Coronary Sinus Describe the features of the following heart chambers: Right Atrium: Interatrial Septum: separate right and left atrium Fossa Ovalis: feature of the atrial wall that is a remnant of the fetal foramen ovale Pectinate Muscles: ridges that contribute to the formation of crista terminalis Tricuspid Valve: gateway between right atrium & right ventricle - AKA: Right Atrioventricular Valve Right Ventricle: Interventricular Septum: separates right and left ventricles Pulmonary Semilunar Valve: gateway between right ventricular & pulmonary artery (start of pulmonary circulation) Trabeculae Carne: bundles of cardiac muscle that make up the interior of the ventricles Papillary Muscles: contract to prevent backflow/regurgitation from the ventricles into the atria Chordae Tendineae: provide tension of papillary muscles to prevent prolapse/inversion of the valve Left Atrium: Collects oxygen rich blood from the 4 Pulmonary Veins Interatrial Septum: separates the right & left atrium Bicuspid Valve: gateway between the left atrium & left ventricle - AKA: Mitral Valve, Left Atrioventricular Valve Left Ventricle: Interventricular Septum: separates the right & left ventricles Aortic Semilunar Valve: gateway between the left atrium & left ventricle **Also contains Trabeculae Carnae, Papillary Muscles & Chordae Tendineae List the 10 steps of blood flow through the heart in your own words: 1. Blood enters the right atrium from the SVC, IVC & Coronary Sinus of the systemic circulation 2. Blood in the right atrium moves through the right atrioventricular valve into right ventricle 3. Contraction of the right ventricle forces pulmonary valve open, blood moves through the pulmonary semilunar valve, into the pulmonary trunk 4. Pulmonary trunk branches into right & left pulmonary arteries 5. Blood distributed by right & left pulmonary arteries to the right & left lungs respectively where it deposits CO2 & loads O2 6. Oxygen rich blood returns to the heart (specifically the left atrium) from the lungs via the pulmonary veins 7. Blood moves through the left atrioventricular valve (mitral valve, bicuspid valve) to enter the left ventricle 8. Contraction of the left ventricle forces aortic semilunar valve open, allowing blood to move into the aorta 9. Blood moves through the three large branches of the aorta: brachiocephalic trunk, left common carotid artery & left subclavian artery 10. Blood in now within the systemic circuit where it is distributed to every organ/tissue of the body allowing for unloading of O2 & loading of CO2 Describe the oxygenation status of the blood flowing through the following structures of the heart: Pulmonary Arteries: Oxygen Poor Left Atrium: Oxygen Rich Pulmonary Veins: Oxygen Rich Left Ventricle: Oxygen Rich Right Atrium: Oxygen Poor Aorta: Oxygen Rich Right Ventricle: Oxygen Poor Superior/Inferior Vena Cava: Oxygen Poor Name the chamber of the heart with the thickest myocardium. Describe why this chamber requires more myocardial tissue than the others: Left Ventricle requires the thickest myocardium because it must strongly contract to propel blood to distant organs/tissues throughout the body. Thicker myocardium = Stronger contraction of cardiac muscle to overcome greater resisting pressure. Label the valves of the heart from a cross-sectional view & indicate if each valve is an Atrioventricular Valve (AV) or Semilunar Valve (SL): Name the primary function of the heart valves: ensure one-way flow of blood; prevent backflow (regurgitation) Describe how pressure differences govern the opening & closure of the heart valves: Blood will flow from areas of high to low pressure. Contraction of the heart increases the pressure within a heart chamber. This increase in pressure produces the pressure gradient that forces the valve open, allowing blood to move to the next location within the circulation of the heart. Describe the location & function of the following heart valves: Atrioventricular Valves (AV): valves located between the atria & ventricle - Bicuspid Valve (Mitral Valve/Left AV Valve): located between left atria & ventricle - Tricuspid Valve (Right AV Valve): located between right atria & ventricle Open: valve cusps project into ventricle, papillary muscles relaxed & chordae tendinae are slack - Pressure difference drives blood to move from atria to ventricle, through the open valve Closed: papillary muscles contract to tighten chordae tendinae attached to the cusps, preventing prolapse of the cusps into the atrium - Pressure buildup in the ventricle pushes the cups out of the ventricle, closing the valve Semilunar (SL) Valves: valves located between ventricles & arteries - Pulmonary Semilunar Valve: located between right ventricle & pulmonary arteries - Aortic Semilunar Valve: located between left ventricle & aorta Pressure differences cause the semilunar valves to be in an open vs closed conformation. - Open: pressure in ventricles > pressure in arteries (occurs when ventricles contract) - Close: pressure in ventricles < pressure in arteries (occurs when ventricles relax) Describe the following valvular pathological conditions: Valve Stenosis: valves cannot fully open, preventing normal blood flow - Valves stiffen & are thicker than healthy valves Valve Regurgitation: incomplete closure of the heart valve allowing backflow of blood - Can be caused by damage to the papillary muscles (prolapse of the heart valves) Define Anastomosis: location in which two or more blood vessels join to form an web - Overlap allows for additional coverage of an area of the heart muscle - Prevents loss of nutrient supply to that area of the heart if one of the blood vessels of the anastomosis becomes blocked. Label the Coronary Arteries & Veins: Name the vessels that branches from the aorta FIRST: Bilateral Coronary Arteries Name the vessels that bring oxygenated blood to the tissues of the heart: Coronary Arteries Describe the the function of the Coronary Sinus including oxygenation status of the blood it carries & where it empties into: Coronary Sinus: drains oxygen poor blood from the coronary veins into the right atrium Name the vessel commonly described as the “widow maker” & describe why its function is essential to cardiac function: Anterior Interventricular Artery- supplies the left ventricle; loss of perfusion to the left ventricle would prevent blood from being pumped through the systemic circuit Anterior Interventricular Artery is also known as the Left Anterior Descending Artery (LAD). - Blockage of this artery is the most common source of fatal myocardial infarctions (heart attacks) Describe the oxygenation status & direction of blood flow of the pulmonary vessels: Pulmonary veins carry oxygen-rich blood toward the heart. Pulmonary arteries carry oxygen poor blood away from the heart KEY: Arteries carry blood away from the heart while veins carry blood toward the heart WEEK 2: Label the following myocardial cell: Label the parts of the cardiac conduction system in sequence of excitation progression: 1. SA Node 2. AV Node 3. AV Bundle 4. AV Bundle Branches 5. Subendocardial Network of Purkinje Fibers Name the structure that allows for transmission of electrical signals directly between neighboring cells: Gap Junctions Name the intrinsic pacemaker of the heart: SA Node: independently initiates electrical depolarization of the myocardium of each heart beath - Independent = without signal from the nervous system Describe the ion movement of the Three Phases of the Cardiac Action Potential: 1. Depolarization: Na+ channels open & Na ions flow into the cell 2. Plateau: Ca++ channels open & Ca ions flow into the cell, triggering contraction 3. Repolarization: K+ channels open & K ions flow out of the cell Describe the steps of the SA Node Action Potential: 1: Cation leak channels allow Na+ to enter the cell, causing depolarization, moving the membrane potential closer to the action potential threshold 2: Once the membrane potential meets the action potential threshold, voltage-gated Na+ channels open, completely depolarizing the cells of the SA Node 3: K+ channels open, repolarizing the membrane 4: K+ channels remain open causing hyperpolarization of the membrane - Leaky cation channels (from step 1) open, restarting the cycle Label the Cardiomyocyte Action Potential Graph: Four Steps of the Cardiomyocyte Action Potential: 1: Depolarization: voltage gated Na channels open 2: Inactivation: voltage gated Na channels inactivate, stopping the flow of Na ions; voltage gated K channels open 3: Plateau: voltage gated Ca++ channels open; voltage gated K channels remain open 4: Repolarization: voltage gated Ca++ channels close; voltage gated K channels remain open, resulting in hyperpolarization Label the key events on the EKG tracing : P Wave, QRS Segment, T wave Describe the three main components of the EKG: P Wave: Atrial Depolarization QRS: Ventricular Depolarization [*Atrial Repolarization hidden within QRS Complex] T wave: Ventricular Repolarization Describe the one word definitions of the following terms: Diastole = Relaxation; Systole = Contraction Describe the electrical, muscular & heart valve events of the following periods of the cardiac cycle: **I have provided the same information in both chart & paragraph forms - use whichever works best for you:) Atrial Diastole: Atrial Relaxation As the atria relax, the volume of the atria increases, causing the pressure to decrease. The myocardium of the ventricle is relaxed and therefore there is no change in the ventricular volume or pressure. The AV valve is close to allow for atrial filling with blood from pulmonary & systemic veins. The SL valve is also closed. There is no heart sound associated with atrial diastole. Atrial relaxation corresponds to & is embedded within the QRS Complex on an EKG. Atrial Systole: Atrial Contraction As the atria contract, the volume of the atria decreases, causing the pressure to increase. The pressure in the aorta continues to increase until atrial pressure becomes greater than ventricular pressure, causing the AV valve to open. The SL valve is closed to allow for ventricular filling. The ventricles are relaxed. The volume of the atria is decreasing while the volume of the ventricle is increasing (blood is moving from atria to ventricle through the AV valve). Atrial systole is represented by the P Wave on an EKG. There is no heart sound associated with atrial systole. Ventricular Diastole: Ventricular Relaxation As the ventricles relax, the volume of the ventricle increases, causing the pressure to decrease. The pressure of the ventricle continues to decrease until the pressure in the aorta/pulmonary trunk is greater than ventricular pressure, causing the SL valves to close. This valve closure produces the S2 heart sound. Ventricular Diastole is represented by the T Wave on an EKG. The myocardium of the atria is relaxed, there is no change in pressure or volume within the atria. The AV valve is closed because the atrial pressure remains lower than the ventricular pressure up to a point in ventricular diastole when the pressure of the atria becomes greater than the pressure within the ventricle, causing the AV valve to open. Ventricular Systole: Ventricular Contraction As the ventricles contract the volume of the ventricle decreases, causing the pressure to increase. The pressure of the ventricles continues to increase until it is greater than the pressure within the arteries (aorta for L Ventricle). The pressure gradient causes the SL valve to open. Upon contraction of the ventricular myocardium, papillary muscles contract, producing tension on the associated chordae tendinae, preventing prolapse of the AV valves into the atria. Closure of the AV valves is caused by the increase in pressure within the ventricles & produces the S2 heart sound. Ventricular systole is represented by the QRS complex on an EKG. The myocardium of the atria is relaxed, there is no change in volume or pressure of the atria. Atrial Diastole: Atrial Systole: Ventricular Diastole: Ventricular Systole: Muscular of Atria: Relaxing Contracting No Movement No Movement Muscular of No movement No Movement Relaxing Contracting Ventricles: SL Valves Closed Closed Closed Open (open/closed): AV Valves Closed Open Closed Closed (open/closed): Atrial Volume Increasing Decreasing No change No change Ventricular Volume No change Increasing Increasing Decreasing Heart Sound: None None S2 S1 Describe what is occurring in the heart during each of the heart sounds: Lubb (S1): Closure of both AV valves as ventricles contract Dupp (S2): Closure of both SL valves as ventricles relax S3: Mitral Valve opens & blood fills the left ventricle Label the following diagram: Define the following statements with regards to pressure & volume in the heart during a contraction cycle: Isovolumetric Contraction: beginning of ventricular systole; ventricle is contracting but volume of ventricle has not yet changed Isovolumetric Relaxation: ventricle as empty as possible & volume of blood in the ventricles is not changing because AV valves are closed End Diastolic Volume (EDV): volume of blood at the end of ventricular diastole - Direct impact on Preload & Ejection Fraction End Systolic Volume (ESV): volume of blood at the end of ventricular systole Ventricular Ejection: Pressure in the ventricle is greater than pressure in the arteries, causing blood to move out of the ventricles & into the arteries (aorta) Ejection Fraction: measure of the heart’s efficiency; percent of the volume of blood the ventricles pump out with each contraction Dicrotic Notch (or Wave): Slight increase and then decrease in pressure within the aorta that occurs after closure of the Aortic Semilunar valve Which of the following the events are captured directly by an EKG: - Atrial Diastole - Ventricular Repolarization - Ventricular Depolarization - Electrical Events of the Heart - Atrial Contraction - Mechanical Events of the Heart Define cardiac output and list a few factors that can influence it: Cardiac Output: amount of blood pumped out of the heart in one minute - Both the amount of blood (SV) and the rate at which it is pumped out (HR) can change, influencing the value of Cardiac Output Write the equation for Cardiac Output: Cardiac Output = (End Diastolic Volume - End Systolic Volume) x Heart Rate CO = (EDV - ESV) x HR CO = SV x HR [Because EDV-ESV = SV] **Think ‘D’ comes before ‘S’ in the alphabet, as it does in the equation Understand the relationship of the variables from the equation above. For example, if the HR decreases, what must occur to stroke volume in order to maintain a constant cardiac output? In the calculation of Cardiac Output, the stroke volume and heart rate are inversely related. - For CO to remain constant , decrease in HR = increase in stroke volume (& vice versa) Define the following terms: Preload: stretch on the right atrium when it is full of blood - Directly related to the amount of blood returned to the atrium by the systemic & pulmonary veins Contractility: how hard the heart contracts - Directly related to preload: more blood returning to the heart must be met with increased ejection force to move that blood out of the heart Afterload: sum of the peripheral resistance hat must be overcome for the heart to eject blood - Directly related to contractility in that an increase in afterload requires a stronger contraction to eject blood from the heart. Describe how change in Preload, Afterload & Contractility would impact Stroke Volume: Increase Stroke Volume: larger volume of blood ejected from the heart during a single contraction - Increase Preload: more blood into atria = more blood ejected - Decrease Afterload: move blood ejected = less resistance in the peripheral vessels - Increased Contractility: more blood ejected = greater force of myocardial contraction Decrease Stroke Volume: smaller volume of blood ejected from the heart during a single contraction - Decrease Preload: less blood into atria = less blood ejected - Increase Afterload: less blood ejected = more resistance in the peripheral vessels - Decrease Contractility: less blood ejected = smaller force of myocardial contraction Describe the relationship between End Diastolic Volume, Preload & Ejection Fraction: End Diastolic Volume volume of blood that remains in the ventricle after a contraction. If the EF is 70%, then the EDV is 30%. Increased EDV results in a decrease in EF because a smaller volume of blood is ejected from the heart during a single contraction as represented by an increase in the volume of blood remaining in the ventricle. The value of preload is directly related to EF. The more blood returned to the atria results in a greater amount of blood ejected from the heart (EF). Increased EF to compensate for an increase in preload allows for EDV to remain constant. Describe how the Frank-Starling Law of the heart influences cardiac output: Frank Starling Law of the Heart: increased preload = increased contractility = larger SV - Stroke volume is directly related to cardiac output. When the preload of the heart increases, the stroke volume also increases to ensure the additional volume of blood entering the atria is ejected back into the pulmonary & systemic circuits. Therefore, increased preload results in higher cardiac output (when HR is constant). Compare and contrast the sympathetic & parasympathetic regulation of the heart: Sympathetic Regulation of the Heart: fight or flight - Increased HR, Increase BP, Increase SV, Increase CO Parasympathetic Regulation of the Heart: rest & digest - Decrease HR, Decrease BP, Decrease DV, Decrease CO Week 3: Label the following generic circulation diagram: Label the following features of cardiac vessels: Arterial Tunica Intima: Tunica Intima of Veins: A: Endothelium I: Endothelium B: Basement Membrane J: Basement Membrane C: Internal Elastic Lamina Tunica Media of Veins: Arterial Tunica Media: K: Smooth Muscle Layer D: Smooth Muscle Cells E: External Elastic Lamina L: Tunica Externa of Veins​ M: Vasa Vasorum F: Arterial Tunica Externa ​ G: Vasa Vasora N: Venous blood flow H: Arterial blood flow ​ O: Capillary Endothelium ​ P: Basement Membrane of Capillary Describe the functions of the 3 layers of blood vessels: Tunica Interna: thinnest layer; provides stretch Tunica Media: vasoconstriction Tunica Externa: supportive connective tissue Name the vessel that supplies each of the following structures: Upper Limb: Subclavian Artery Head & Brain: Common Carotid Artery Lower Limb/Pelvis: Common Iliac Artery Intestines: Superior Mesenteric Artery Spine: Vertebral Artery Anterior/Lateral Arm: Cephalic Vein Liver, Spleen, Stomach: Celiac Artery Name the structures supplied by the unpaired branches of the abdominal aorta: Celiac Trunk: Liver, Gallbladder, Stomach, Spleen Superior Mesenteric Artery: Small intestine & portions of Large Intestine Inferior Mesenteric Artery: portions of Large Intestine Label the following axial vessels: Label the following appendicular vessels: Describe the 3 main reasons that veins are different than arteries: 1: Layers: veins have thinner tunica interna & media layers + lack elastic lamina 2: Valves: veins have flap like cusps that extend into the lumen; prevent backflow of venous blood 3: Little to no Muscle: veins have an inconsequential smooth muscle layer; rely on surrounding skeletal muscle to pump venous blood against gravity to return to the heart Name the structure that controls blood flow through the capillary bed: Precapillary sphincters control the flow of blood through a capillary bed: - Open precapillary sphincter = allows blood to move through The purpose of the precapillary sphincters is to divert blood to areas of the body that require more nutrients: - Sympathetic activation = divert blood to skeletal muscle - Parasympathetic activation = divert blood to the digestive system Describe the Three Types of Capillaries: Continuous Capillaries: no fenestrations; make up blood brain barrier Fenestrated Capillaries: many small fenestrations; located in kidneys & function in filtration Sinusoids: large fenestrations, large intercellular clefts; located in spleen & liver Define Capillary Exchange: Capillary Exchange: movement of substances between the blood and interstitial fluid (tissues). Name the force most responsible for capillary exchange: Diffusion *Filtration & Reabsorption are both types of diffusion Name the factor that is most essential for the movement of blood through veins: Skeletal Muscle Activity Name the vessel(s) that serves as the LARGEST blood reservoir: Veins & Venules Define Peripheral Resistance: Peripheral Resistance: force of resistance a blood vessel exerts against the movement of blood through the vessel. Describe how the following factors influence peripheral resistance: Lumen Size: Larger diameter of lumen = decrease peripheral resistance (inverse relationship) Blood Viscosity: higher viscosity increases resistance (direct relationship) Vessel Length: Longer vessel length increases resistance (direct relationship) Name the structure of the brain that regulates blood pressure: Medulla Oblongata Briefly describe the four hormonal mechanisms that regulate blood pressure: 1. Renin-Angiotensin-Aldosterone System: increases BP 2. Epinephrine/Norepinephrine: change diameter of vessels (decrease BP) 3. Antidiuretic Hormone: stimulates vasoconstriction (increase BP) 4. Atrial Natriuretic Peptide: decrease BP Classify the following defenses into first and second lines of the innate immune system response: Mucus Membranes, Natural Killer Cells, Phagocytes, Skin, Lysozyme, Fever, Secreted Fluids/Chemicals, pH Control, Inflammation, Defecation/Vomiting First Line: Skin, Mucus Membranes, Secreted Fluids/Chemicals, Defecation/Vomiting, Lysozyme, pH Control Second Line: NK Cells, Phagocytes, Inflammation, Fever Compare and contrast the innate and adaptive immune systems: Innate: nonspecific defense against pathogens present at birth - Purpose: prevent pathogens from accessing tissues and establishing an infection Adaptive: specific defense against pathogens that develops with time; capacity for memory - Purpose: respond to pathogens that have invaded and established an infection - Vaccines target the adaptive portion of the immune system Describe the function of Lymphatic Capillaries: Lymphatic Capillaries are one way vessels that drain interstitial fluid to a lymph node for immune surveillance. Describe the function of Lacteals: Absorption of dietary lipids from the digestive tract. Describe the following terminal vessels of the lymphatic system: Thoracic Duct: main duct that drains lymph from all structures not served by the right lymphatic duct; empties into left subclavian vein; originates as the cisterna chyli in the abdomen Right Lymphatic Duct: drains lymph from only the right arm, right chest & right head/neck; empties into the right subclavian vein Name and describe the functions of the two primary lymphatic organs/tissues: Primary Lymphatic Organs: site of cell division resulting in the production of immune cells 1. Red Bone Marrow: Production of B & T Cells from stem cells; site of B Cell maturation 2. Thymus: site multiplication & maturation of T Cells Name & describe the functions of the three secondary lymphatic organs/tissues: Secondary Lymphatic Organs: site of adaptive immune response 1. Lymphatic Follicles of the Tonsils/Appendix/Colon: small patches of lymphatic tissues located in specific location within the body 2. Lymph Nodes: filter foreign substances drained in the lymph; provide signal to the immune cells that a pathogen is present & a response is needed 3. Spleen: removes old blood cells (both red & white blood cells) Name the major type of tissue located in lymph nodes & describe the function of this tissue type with respect to the overall function of lymph nodes: Reticular Connective Tissue: functions as a filter to trap pathogens & other foreign materials in the lymph nodes Describe the flow of lymph drainage from distal parts of the body and how this related to metastasis of cancer: Lymph drains first to the most proximal lymph nodes. Nodes within close proximity of the cancer source are sampled to evaluate for metastasis of the cancerous cells. Describe the two types of tissue masses of the spleen: White Pulp: processes dead & dying White Blood Cells Red Pulp: processes dead & dying Red Blood Cells Name the structure that lymphatic follicles lack that prevent them from being classified as an organ: Lymphatic Follicles do not have a capsule- they are simply a group of cells that function in immune surveillance.