Anaphy Semi-Finals Reviewer PDF

Movement of blood is driven by pressure ANAPHY SEMI-FINALS gradient REVIEWER - Blood moves from areas of higher pressure to areas of lower pressure...

Movement of blood is driven by pressure ANAPHY SEMI-FINALS gradient REVIEWER - Blood moves from areas of higher pressure to areas of lower pressure - Referred to as bulk flow By: Ortiz, Nicole Angeline (BSN-1G) Blood thickness (viscosity) causes Sarmiento, Mark Justine (BSN-1K) resistance to flow - Thicker blood has more resistance CARDIOVASCULAR SYSTEM: Resistance influenced by plasma proteins and BLOOD formed elements NOTE: Womens are more prone to dehydration BLOOD because of their hormones ( progesterone and - a fluid connective tissue estrogen) it attracts more fats, since fats are oil PLASMA and water cannot mixed with oil. - liquid extracellular matrix HEART - creates a pressure gradient that helps move blood through the body FUNCTIONS OF HEART TRANSPORT - Transports nutrients, wastes, and other substances as it moves throughout body DEFENSE - White blood cells provide protection against infection - Platelets protect from blood loss MAINTENANCE OF HOMEOSTASIS - Aids in temperature and pH regulation and fluid balance PLASMA WHOLE BLOOD - Mainly water (92%) - Components of whole blood can be - Contains plasma proteins ( Albumins, separated by a centrifuge globulins, fibrinogen ) CELLULAR COMPONENTS - Most produced by liver - Red blood cells (Erythrocytes) - Other solutes - White blood cells (Leukocytes - Nutrients, gasses, wastes, regulatory - Platelets (cytoplasmic fragments, not substances, electrolytes Includes ions, glucose, entire cells)(Thrombocytes) lipids, oxygen, carbon dioxide, and amino acids PLASMA PROTEINS ANATOMY OF FLOW - Account for approximately 7% of plasma volume  - Albumins are the most abundant plasma - Saturation of hemoglobin with oxygen protein detected by pulse oximeter - Made by liver - Oxygenated blood carries higher - Major regulator of blood osmotic amounts of oxygen pressure - 95-100% saturated - Globulins are second most abundant - Deoxygenated blood carries less plasma proteins oxygen - Function as transport proteins - Usually 70-80% oxygenated and as antibodies ERYTHROPOIESIS - Many are produced by liver; - Production of red blood cells antibodies are produced by leukocytes - Begins in red bone marrow Fibrinogen is least abundant plasma protein - Stimulated by erythropoietin (EPO) - Involved in blood clotting - A hormone secreted in response - Produced by liver to hypoxemia BLOOD COMPONENTS - Results in formation of new RBCs - If all necessary components are available - Such as iron and vitamin B12 NOTE: RBC can live for only 120 days ERYTHROCYTES ( No Nucleus) - Most common formed element - Transport gasses in the blood - Biconcave disc shape - Increases surface area for gas exchange - Contain hemoglobin to transport glasses HEMATOCRIT HEMOGLOBIN - Made of proteins and iron - Four folded globin proteins contain four heme groups - Each heme group contains an iron ion (Fe2+) - Can bind one molecule of oxygen - Binds oxygen in oxygen-rich ANEMIAS environments - Releases oxygen in oxygen-poor environments NOTE: 1 Hemoglobin = carries four oxygen PULSE OXIMETRY  leukocyte second most common (40–60%) - Faint purple leukocyte (20–30%) granules - Large nucleus - Nucleus has two with a thin rim to five lobes of cytoplasm - Phagocytosis Three groups: ( cell eating ) 1. B lymphocytes - Phinocytosis (cell 2. T lymphocytes drinking) 3. Natural Killer (NK) - increase during cells LEUKOCYTES (WBC) bacterial infections - —increase - Also known as white blood cells during viral - Help protect the body against infection infections - Eliminate body cells with mutated DNA Eosinophils Monocytes - Clean up debris PLATELETS - Involved in blood clotting and vessel repair CHARACTERISTICS OF LEUKOCYTES - Produced by hematopoiesis in red bone marrow - (2-4% of - Large, with a - Less numerous than RBCs leukocyte count) horseshoe - Larger in size than RBCs - Bright pink to red shaped nucleus - All have a nucleus and organelles granules - Phagocytes - Nucleus has two to - Mature into - Can last hours to years three lobes macrophages - Leave blood vessels via diapedesis - Fixed versus - increase during - Attracted to areas where needed parasitic infections wandering by chemotaxis macrophages - increase during viral or fungal Granular leukocytes Agranular leukocytes infections - have granules that - have granules, can be seen but not easily seen Basophils Neutrophils Lymphocytes - least common leukocyte (less - most common than 1% of  - Process of producing formed elements leukocyte count) - Dark blue - Begins in red bone marrow granules - Hematopoietic stem cells can - Nucleus with two differentiate into any formed element lobes - Differentiate into lymphoid or myeloid - Granules release stem cells first histamine HEMATOPOIETIC GROWTH FACTORS - increase during allergic reactions - Differentiation of hematopoietic stem cells is driven by chemical growth factors, some of which are also hormones ERYTHROPOIETIN(EPO) - promotes erythrocyte production called erythropoiesis THROMBOPOIETIN - promotes development of megakaryocytes and platelets CYTOKINES - chemical signals released from a variety ANATOMY OF LEUKOCYTES of tissues - Stimulate production of various leukocytes as necessary PROCESS OF HEMOSTASIS 1. VASCULAR SPASM - Smooth muscle in walls of blood vessels contracts - Limits blood flow to area and blood loss - Continues for approximately 30 minutes - Decreases blood flow and blood loss from damaged area - Allows other steps of hemostasis to occur 2. FORMATION OF PLATELET PLUG PLATELETS - Platelets adhere to exposed - Platelets are not cells collagen fibers in vessel wall - Fragments of a megakaryocyte - Release ADP, serotonin, - Contain growth factors and chemicals and prostaglandins involved in blood clotting -Recruits more platelets and - Also help promote repair of blood maintains vasoconstriction vessels and tissue healing - Activated platelets attract more HEMATOPOIESIS platelets to damaged area,  leading to more activated Response is faster in Response is slower than platelets comparison to the extrinsic pathway -This is a positive feedback intrinsic pathway loop Factor III enters vessel Factor XII comes in from tissues due to contact with foreign damage material - Forms platelet plug -Von Willebrand factor helps Factor III activates Factor Activated factor XII stabilize plug and bind it to VII that will combine activates factor XI which collagen with calcium to form an will then activate factor 3. COAGULATION (Blood clotting) enzyme complex IX - Failure of these steps leads to This enzyme complex Activated factor IX hemorrhage will activate factor X combines with factor VIII FIBRIN AND COAGULATION to activate factor X - Coagulation involves a cascade of Requires presence of events that allows repair of vessel calcium - Soluble fibrinogen will be converted Enters common pathway Enters common pathway into insoluble fibrin to stabilize platelet after activation of factor after activation of factor plug into a clot X X - Individual fibrin proteins combine -Form a netlike protein that stabilizes COMMON PATHWAY plug - Both extrinsic and intrinsic pathways COAGULATION lead to the common pathway - Two pathways initiate coagulation: - Prothrombinase converts factor II -Extrinsic pathway triggered by trauma (prothrombin) into thrombin that breaks blood vessel wall - Thrombin converts factor I (fibrinogen) -Intrinsic pathway triggered by internal into fibrin that stabilizes clot damage to wall FIBRINOLYSIS - Third pathway is the common pathway - Once clot is formed, its edges are pulled - Both the extrinsic and intrinsic toward each other as vessel heals pathways lead to the common pathway - Clot is eventually removed by - All three pathways are dependent on the fibrinolysis presence of calcium and vitamin K - Gradual degradation of the clot - To accomplish this, plasminogen is Clotting Factors Involved in Coagulation activated into plasmin - Clotting factors prompt reactions - Plasmin breaks down fibrin to dissolve associated with coagulation clot - Bradykinin causes vasodilation to Extrinsic Pathway Intrinsic Pathway restore blood flow PLASMA ANTICOAGULANTS Activated by tissue Activated by internal trauma that breaks the damage to the wall of the - Substances that oppose coagulation wall of the blood vessel vessel ANTITHROMBIN - Inactivates factor X  - Opposes conversion of prothrombin - In the ABO blood group system, there into thrombin are two types of antigens, type A antigen and type B antigen. HEPARIN - Type A blood has type A antigens, type - Opposes prothrombin B blood has type B antigens, and type - Found on endothelial cells to prevent AB blood has both types of antigens. abnormal clots - Type O blood has neither A nor B ANTIGENS antigens. - Molecules or groups of molecules the - The types of antigens found on the body does not recognize as “self” surface of the red blood cells are -Trigger an immune response genetically determined. - Found on surface of red blood cells - Antibodies against the antigens are - Basis for blood types usually present in the plasma of blood. - Can also cause transfusion reactions - Plasma from type A blood contains anti when incompatible blood types are mixed -B antibodies, which act against type B ERYTHROCYTES ANTIGENS antigens; plasma from type B blood - Blood types are determined based on contains anti -A antibodies, which act the antigens present on the surface of against type A antigens. RBCs - Type AB blood plasma has neither type - Only three antigens commonly used: of antibody, and type O blood plasma - Antigen A has both anti -A and anti -B antibodies - Antigen B - Antigen D (Rh factor) - Based on presence or absence of A - Negative or positive blood type antigen and B antigen ANTIBODIES - Type A—A antigen only - Proteins that are made by the immune - Type B—B antigen only system - Type AB—A and B antigens - Designed to bind to foreign antigens the - Type O—neither antigen body doesn’t recognize - Antibodies produced against antigen(s) - Forms antigen-antibody not present on a person’s red blood cell complexes - Antigen-antibody complexes can initiate transfusion reactions - Cells agglutinate in response -Stick together” TRANSFUSIONS REACTIONS - Occurs when incompatible blood types are mixed -Cells clump together - Hemolysis of red blood cells can overload kidneys -Can lead to kidney failure ABO BLOOD GROUPS Blood Donor and Recipient According to ABO Blood Types  - O are universal donors because they have no antigens - Type A can receive A and O blood - Type B can receive B and O blood - Type AB are universal recipients, can receive A, B, AB or O blood - Type O can only receive O blood RH BLOOD GROUP - Rh positive means you have Rh HEMOLYTIC DISEASE OF NEWBORN antigens - occurs when mother produces anti-Rh - 95 to 85% of the population is Rh+ antibodies that cross placenta and - Antibodies only develop if an Rh person agglutination and hemolysis of fetal is exposed to Rh+ blood by transfusion erythrocytes occurs or from mother to fetus - can be fatal to fetus - prevented if mother is treated with Hemolytic Disease of a Newborn (HDN) RhoGAM which contains antibodies - Can possibly occur when a Rh– mother against Rh antigens is pregnant with an Rh+ fetus - Rare in first pregnancy, but BLOOD TYPING complications may arise with second pregnancy - During first delivery, mother may be exposed to Rh antigen during birth - Anti-Rh antibodies will be produced in between pregnancies - If the second fetus is also Rh+, the antibodies the mother made will cross BLOOD TRANSFUSIONS placenta and cause hemolysis - Risk of transfusion immune reactions Rh INCOMPATIBILITY WITH requires a recipient to receive only PREGNANCY compatible blood types - If mother is Rh - and fetus is Rh+ the - An individual should only receive mother can be exposed to Rh+ blood if blood that does not contain antibodies fetal blood leaks through placenta and against their own blood type mixes with mother’s blood. Example: - First time this occurs mother’s blood - If the recipient is O- (O negative), they produces antibodies against antigens. contain antibodies against the A antigen - Any repeated mixing of blood causes a and B antigen in their blood reaction. - This recipient should not receive any blood with the A or B antigen on the surface of the RBC of the donor - Due to risk of producing Rh antibodies, they should not receive blood with the Rh antigen either  - They can only receive O negative blood Right Atrium - receives deoxygenated blood from CARDIOVASCULAR SYSTEM: HEART systemic circuits HEART Left Atrium - receives oxygenated blood from - located within the mediastinum of the pulmonary circuits thoracic cavity. - is a muscular organ that pumps blood Ventricles throughout the body, delivering oxygen - inferior chambers and nutrients to the body's tissues and organs. Right Ventricle - Pericardium surrounds the heart, - ejects deoxygenated blood into forming a pericardial cavity. pulmonary trunk - Base is the posterior site where great vessels attach to the heart. Pulmonary Trunk - Apex is the inferior tip of the heart. - divides into pulmonary arteries and sends blood to lungs EMBRYONIC DEVELOPMENT OF THE HEART Left Ventricle - ejects oxygenated blood into aorta - the embryonic heart folds on itself at 24 and 35 days of gestation. HUMAN CIRCULATION - Congenital heart defects (CHDs) may occur if development proceeds Two systems of blood vessels in human incorrectly. circulation: Systemic Circuit - Transports oxygenated blood to tissues and returns deoxygenated blood back to heart Pulmonary Circuit - Transports deoxygenated blood from heart to lungs and returns oxygenated blood back to heart CHAMBERS OF THE HEART Blood circulates through the heart in the following order: Atria - superior chambers - Vena Cava - Right Atrium - Tricuspid Valve - Right Ventricle  - Pulmonary Valve LAYERS OF THE HEART WALL - Pulmonary Artery - Capillaries in the Lungs Epicardium - Pulmonary Vein - most superficial, same as visceral layer - Left Atrium of serous pericardium - Bicuspid Valve - Left Ventricle Myocardium - Aortic Valve - contains cardiac muscle, thickest layer - Aorta of heart wall, contains collagenous - Capillaries in the Body/Peripheral framework of heart, blood vessels, and Tissues nerves - Vice Versa Endocardium - deepest layer, simple squamous epithelium, continuous with endothelium of blood vessels PERICARDIUM - membranous sac that surrounds the heart Fibrous Pericardium ORIENTATION OF CARDIAC MUSCLE - attaches heart to diaphragm FIBERS Serous Pericardium - cardiac muscle fibers are oriented for - reduces the friction as heart beats effective contraction - fibers wrap around each atrium FORMATION OF SEROUS PERICARDIUM - serous pericardium begins as a fluid-filled sac - as heart enlarges, it pushes into the sac  - valves prevent blood from moving in the wrong direction and prevent the backflow of the blood Atrioventricular (AV) valves - located between atria and ventricles - Tricuspid valve on right - Bicuspid valve on left Semilunar (SL) valves - located at exit points of heart INTERATRIAL SEPTUM OF THE HEART - Pulmonary valve on right - Aortic valve on left - Interatrial septum located between atria - Contains fossa ovalis - Oval shaped depression - Remnant of foramen ovale of fetal heart that allowed blood to bypass pulmonary circuit Atrial Septal Defect - a congenital heart defect in which blood flows between the atria of the heart where in there is a hole between the upper heart chambers Right Atrium - Receives deoxygenated blood from the systemic circuit - Via the super vena cava, inferior vena cava, and coronary sinus - Fills with venous blood during atrial relaxation - Venous return Interventricular Septum Right Ventricle - located between ventricles, more - Receives deoxygenated blood from the muscular than interatrial septum right atrium - Blood initially passes through the open HEART VALVES tricuspid valve first - Walls contain ridges of muscle called trabeculae carneae  - Pressure increases during ventricular - Plaque buildup decreased coronary contraction blood flow - Blockages visible on coronary Left Ventricle angiogram - Receives oxygenated blood from left - Can lead to hypoxia and myocardial atrium ischemia - Contraction closes bicuspid valve and opens aortic semilunar valve CARDIAC MUSCLE - Ejects oxygenated blood into the aorta and into the systemic circuit - Referred to as autorhythmicity - Heart continues to beat when removed Left Atrium from body - After gas exchange in the lungs, - “Heart-in-a-Box” machine circulates oxygenated blood returns to left atrium oxygenated blood through donor hearts - Via pulmonary veins - Heart rate can be manipulated by - Auricle contains pectinate muscles nervous and endocrine system - Fills during atrial relaxation - Ejects blood through open bicuspid Characteristics of Cardiac Muscle (mitral) valve into left ventricle - Branching fibers connected by intercalated discs HEART VALVE DISORDERS - Striated—contractile unit is sarcomere - Myocardial contractile cells—pass - Regurgitation occurs when valves action potentials from one cell to allow blood to move in wrong direction another (e.g., from ventricle into the atrium) - Myocardial conducting - Valve stenosis occurs when valves cells—generate and conduct action become calcified potential through heart Coronary Arteries Structure of Contractile Cardiac Muscle - Left and right coronary arteries - Contain myofilaments arranged into - Left coronary artery branches to form sarcomeres circumflex artery and anterior interventricular artery Heart Disease and Cardiac Muscle Coronary Veins - Heart disease and heart attacks cause - Great cardiac vein damage to cardiac muscle - Small cardiac vein accompanies right - Cardiac muscle does not regenerate yet coronary artery is replaced by noncontractile scar tissue - Most cardiac veins drain into coronary sulcus Propagation of Cardiac Action Potential - SA node depolarizes spontaneously, CORONARY ARTERIES DISEASE known as the "pacemaker" of the heart - Depolarization spreads quickly over both atria  - AV node slows down movement and conducts depolarization into ventricle - AV Bundle, left and right AV bundle branches, Purkinje fibers depolarize ventricles Electrocardiogram (EKG) - record of electrical events in heart - diagnosis cardiac abnormalities - uses electrodes - contains P wave, QRS complex, T wave Functions of the Respiratory System Fibrillation The function of the Respiratory System - Ventricular fibrillation is life-threatening includes… due to ineffective pumping of blood - Gas exchange - A defibrillator can be used to correct - Speech abnormal heart rhythms - Immune protection - pH homeostasis RESPIRATORY SYSTEM - Olfaction Main Parts of the Respiratory System It consists of… - Nasal Cavity - Nostril - Oral Cavity Visualization of Gas Exchange - Pharynx - Larynx - Trachea - Bronchus (left and right) - Lungs (left and right) - Diaphragm - Alveoli Two physiological divisions of the respiratory system:  - Conducting zone—components air - Nasal septum divides it in half simply travels through - Respiratory zone—areas where gasses Nasal Cavity are exchange - Space within skull that communicates with external nose Conducting Zone - Divided by nasal septum - Provides passageways for air to - Help lighten the skull and allow for reach respiratory zone resonance of voice - Helps to filter, warm, and humidify incoming air Main Functions of Nasal Cavity - Consists of: - Serves as a passageway for air - - External nose, nasal cavity, remains open even when the mouth is pharynx, larynx, trachea, and full of food several airways within the lungs - Cleans the air - The nasal cavity is lined with hairs, which trap some of the Upper respiratory tract large particles of dust in the air - structures found in the head and neck - Humidifies and warms the air - Moisture is added to the air as it passes Lower respiratory tract through the nasal cavity - structures found in thorax - Contains the olfactory epithelium - the sensory organ for smell, is located in the most superior part of the nasal cavity - Helps determine voice sound - The nasal cavity and paranasal sinuses are resonating chambers for speech The Nose - Major entrance and exit of the air - Alar cartilage support and help form nostrils (openings) - External nose—composed of mainly of hyaline cartilage - Nasal cavity—extends from nares Respiratory Epithelium (nostrils) to the choana which are the - Nares and anterior nasal cavity lined by openings to pharynx mucous membranes - Hard palate is its roof  - Olfactory epithelium detects smell in nasal cavity - Conchae, meatuses, and sinuses lined by respiratory epithelium - Pseudostratified columnar epithelium Larynx - Entrance to lower respiratory tract - Also known as “voice box” - Composed cartilage: Thyroid cartilage is largest cartilage; contains thyroid Pharynx (throat) prominence (also known as the - Passageway for the respiratory and “Adam's apple”) digestive systems - Epiglottis protects airway during - Nasopharynx: takes in air swallowing - Oropharynx: extends from uvula to - Consists of 9 cartilages epiglottis; takes in food, drink, and air - Laryngopharynx: extends from epiglottis to esophagus; food and drink pass through The Vocal Cords - Glottis = space below epiglottis - Vocal folds vibrate to produce sound Pharynx Vestibular folds: - Uvula: “little grape,” extension of soft - false vocal cords palate - Pharyngeal tonsil: aids in defending Vocal Folds: against infections - source of voice production - air moves past them, they vibrate, and sound is produced - force of air determine loudness  - tension determines pitch Changes in Air Passageway Diameter Trachea (Windpipe) - Bronchodilation - the smooth muscle - Extends from larynx into mediastinum relaxes, making the bronchiole diameter - Reinforced by C-shaped tracheal rings larger made of hyaline cartilage - Bronchoconstriction - the smooth - Allows for expansion of esophagus muscle contracts, making the bronchiole - Consists of 16 to 20 C-shaped pieces of diameter smaller cartilage called tracheal rings - Asthma attack - contraction of terminal - Lined with ciliated pseudostratified bronchioles leads to reduced air flow columnar epithelium - Smoking kills cilia Bronchial Tree - Collective name for airways within the lungs - Passageways for air to move in and out of each lung - Begins with left and right primary bronchi Tracheobronchial Tree - Structures become smaller and more numerous from primary bronchi to alveoli. - Primary bronchi - Lobar (secondary) bronchi Bronchi - Segmental (tertiary) bronchi - Divides into right and left main - Bronchioles (primary) bronchi in the lungs at the - Terminal bronchioles carina - Respiratory bronchioles - Lined with cilia - Alveolar ducts - Contain C-shaped pieces of cartilage - Alveoli Bronchioles  - Bronchi eventually branch into - Respiratory bronchioles have a few bronchioles attached alveoli - Smallest terminal bronchioles - Alveolar ducts arise from the (respiratory bronchioles) branch and respiratory bronchioles and open into allow air to enter respiratory zone alveoli - Bronchioles have smooth muscle to - Alveolar sacs are chambers connected support their walls, yet no cartilage to two or more alveoli at the end - Muscle allows for bronchodilation or bronchoconstriction Respiratory Zone Surfactant - Pulmonary capillaries allow gas - A mixture of lipoproteins exchange between the lungs and blood - Is produced by secretory cells of the - Consists of respiratory bronchioles, alveoli alveolar ducts, and alveolar sacs made - Is a fluid layer on the surface lining the of individual alveoli alveoli - Reduces surface tension Alveoli - Keeps lungs from collapsing - Thin walls allow gas exchange - Type I alveolar cells are simple Gas Exchange Across the Respiratory squamous epithelium Membrane - Type II alveolar cells secrete surfactant - Respiratory membrane is a thin barrier to reduce surface tension to allow gas exchange to occur - Alveolar macrophages protect against - Formed by type I alveolar cells, a infection basement membrane, and endothelial - The sites of external respiration are the cells of pulmonary capillaries alveoli. - Oxygen diffuses from alveoli into blood - Small air-filled sacs where air and blood - Carbon dioxide diffuses from blood into come into close contact alveolus - Where gas exchange occurs - Surrounded by capillaries Anatomy of the Lungs  - Surrounded by pleural membranes nerves, lymphatics, and primary bronchi - Pleural cavity between the two layers enter or leave each lung contains pleural fluid - Pulmonary arteries bring - Reduces friction due to movement of deoxygenated blood to the lungs lungs - Pulmonary capillaries allow gas - Aids in expansion of lungs during exchange to take place inhalation - Pulmonary veins carry oxygenated - Apex = superior point of lung blood - Base = broad, inferior bottom of the lung Processes of the Respiratory System - The respiratory system delivers oxygen Right lung has three lobes to the cells of the body for use in aerobic - Superior, middle, and inferior respiration - Separated by horizontal and oblique - To deliver this oxygen, the respiratory fissures system carries out the following processes: Left lung has two lobes - Aerobic respiration allows the body to - Separated by oblique fissure produce large amounts of ATP - Contains cardiac notch - Ventilation allows gas exchange across - Indentation for apex of the heart the respiratory membrane, gas transport, and gas exchange between the blood and tissues Pressure of the Lungs - Intrapulmonary pressure = pressure within alveoli - Intrapleural pressure = pressure within pleural cavity - Transpulmonary pressure = difference between intrapleural and intrapulmonary Hilum of the Lung pressures - Hilum is an anatomical structure where pulmonary arteries, pulmonary veins, Ventilation - Expiratory reserve volume (ERV): - The movement of air into and out of the volume of air that can be expired lungs forcefully after a normal expiration - Divided into inhalation (inspiration) and - Residual volume (RV): volume of air exhalation (expiration) remaining in lungs after a maximal - Inhalation—air enters lungs expiration (can’t be measured with - Exhalation—air exits lungs spirometer) Factors Affecting Ventilation - Gender - Age - Body Size - Physical Fitness Muscles of inspiration: increase the volume of the thoracic cavity. - diaphragm - external intercostals - pectoralis minor - scalene muscles The Pleurae - Parietal pleura tightly adheres to thoracic wall due to cohesion - During expansion of thoracic wall, both pleurae and surface of lung also expand - This expansion allows intrapleural pressure to remain below intrapulmonary pressure Pulmonary Volumes - Spirometer: device that measures pulmonary volumes - Tidal volume (TV): volume of air inspired and expired during quiet breathing - Inspiratory reserve volume (IRV): volume of air that can be inspired forcefully after a normal inspiration