BIOL 244 Anatomy and Physiology II Study Guide for Exam II
BIOL 244 Anatomy and Physiology II Study Guide for Exam II BIOL 244
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This 22 page Study Guide was uploaded by Julia Lensch on Monday February 29, 2016. The Study Guide belongs to BIOL 244 at University of South Carolina taught by Dr. Anil Datt in Winter 2016. Since its upload, it has received 161 views. For similar materials see Human Anatomy and Physiology II in Biology at University of South Carolina.
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Lensch Study Guide for BIOL 244 Exam II Chapter 19 The Cardiovascular System: Blood Vessels Arteries Elastic Layers: Internal Elastic Membrane External Elastic Membrane Thicker muscular layer Lumen more narrow Three types of tissues 1. Tunica Intima Endothelium Internal Elastic Membrane 2. Tunica Media Smooth muscle and elastic fibers External Elastic Membrane 3. Tunica Externa Collagen fibers Vasa vasorum Veins Valves Thinner muscular layer Lumen more wide Capillaries One basement membrane layer Endothelial cells Fenestrated Capillary Endothelial Cells 1 of 22 Lensch Endothelial Nucleus Fenestrations (pores) Basement Membrane Arterial Blood Pressure => pressure of blood on walls of arteries Highest => Aorta Lowest => Venae Cavae Renal Control of Blood Pressure (2 ways) Increase Renin release from kidneys (more fluid, more blood, increased pressure) [Angiotensinogen (nonfunctional chemical) --> Angiotensin I --> Angiotensin II (functional chemical)] ==> Decreased filtration by kidneys ==> Erythropoietin (more thickness and pressure) ==> Increase of red blood cells ==> Increased viscosity (thickness) Angiotensin II (functional chemical) ==> 4 different: Adrenal Cortex Increase of ADH release by posterior pituitary (retain 2 O, more volume, more pressure) Increase thirst (more BP) Vasoconstriction; increase peripheral resistance (more BP) 2 of 22 Lensch Distribution of Blood Flow At rest, cardiac output (CO) => 5.5L (5800 mL) Exercise, CO => increased by at least 3 times (17,500 mL) Majority of blood goes to skeletal muscles Blood Flow Velocity and Total Cross-Sectional Area Area: Lowest => Aorta and Venae Cavae Highest => Capillaries Velocity: Lowest => Capillaries Highest => Aorta Affecting Blood Pressure Hormone(s) Site of Action Effect on Variable Variable Result Epinephrine and Heart (β 1 ↑ Heart Rate (HR) Cardiac Output ↑ Blood Pressure 3 of 22 Lensch Norepinephrine(NE) receptors) and Contractility (CO) (BP) Angiotensin II Arterioles ↑ (via Peripheral ↑ BP vasoconstriction) Resistance (PR) Antidiuretic Arterioles ↑ (via PR ↑ BP Hormone vasoconstriction) Epinephrine and Arterioles (α ↑ (via PR ↑ BP Norepinephrine receptors) vasoconstriction) Epinephrine and Large veins (2 ↓ (via PR ↓ BP NE, Atrial receptors)and vasodilation) NatriureticPeptide Arterioles (NO) (Nitric Oxide = NO) Atrial Natriuretic Kidney Tubule ↓ (salt and water Blood Volume ↓ BP Peptide (ANP) (Rt. Cells loss) Atrium) Aldosterone and Kidney Tubule ↑ (salt and water Blood Volume ↑ BP Cortisol Cells retention) Antidiuretic Kidney Tubule ↑ (water Blood Volume ↑ BP Hormone (ADH) Cells retention) Circulatory Shock ↓ Blood circulation ==> ↓ blood flow ==> low O2++ to tissue = ?? Hypovolemic Shock: Causes: ? ? ? Lack of Blood (↓ volume) ==> weak "thready" pulse ↓ BP Vascular Shock: Normal blood volume, but extreme vasodilation Causes: Loss of vasomotor ↓ peripheral resistance (↓ BP) tone due to: Anaphylaxis (allergic reaction <==> ↑ histamine) Septicemia (bacterial toxins ==> vasodilation Cardiogenic Shock: ( = ↓ heart pumping) M.I., ↓ Ca 4 of 22 Lensch Neurogenic Shock Cause: Spinal cord injury Anesthesis ==> loss of sympathetic stimulation Venous Return => volume of blood flowing back to heart Factors Involve: Pressure in the Right Atrium ↑ pressure => ↓ return (** weak valve in the heart) Skeletal Muscle Pump More blood moves => ↑ contraction, ↓ return => ↑ pressure on veins (** arms and legs) Valve in the Veins Weak valve = backflow => ↓ return (** arm and legs) Respiratory Pump Deeper inspiration = squeezing the local veins = ↑ pressure in abdominal cavity = ↑ blood volume to move Blood Pressure Increases when... Blood volume increases Blood viscosity increases Peripheral resistance increases (vasoconstriction) Heart rate increases ↑ CO 2 Stroke volume increases ↑ CO 2 Distribution of Blood in Cardiovascular System 1. Systemic Arterial System (13%) Aorta 2% Elastic Arteries 4% 5 of 22 Lensch Muscular Arteries 5% Arterioles 2% 2. Systemic Venous System (64%) Large veins 18% Venous reservoirs 21% Venules or medium-sized veins 25% 3. Heart (7%) 4. Pulmonary Circuit (9%) Pulmonary Arteries 3% Pulmonary Capillaries 2% Pulmonary Veins 4% 5. Systemic Capillaries (7%) Chapter 20 The Lymphatic System and Lymphoid Organs and Tissues The lymphatic system returns fluids that have leaked from the blood vascular system back to the blood. It consists of three parts: Lymphatic vessels Lymph, the fluid contained in those vessels Lymph nodes that cleanse the lymph as it passes through them The lymphoid organs and tissues provide the structural basis of the immune system. These organs and tissues house phagocytic cells and lymphocytes which play essential roles in the body's defense mechanisms and its resistance to disease The hydrostatic and colloid osmotic pressures force fluid out of the blood at the arterial ends of the beds and most is reabsorbed at the venous ends. The remaining fluid becomes interstitial fluid. Once interstitial fluid enters the lymphatic vessels, it is called lymph Transport of lymph begins in the lymphatic capillaries Two structural modifications: The endothelial cells forming the walls of lymphatic capillaries are not tightly joined, but rather they overlap loosely forming minivalves Collagen filaments anchor the endothelial cells to surrounding structures so that any increase in interstitial fluid results in the opening of minivalves When the pressure in greater inside the lymphatic capillary, it forces the minivalve to shut This prevents the lymph from leaking back out 6 of 22 Lensch Lymphatics in the skin travel along with superficial veins, while the deep lymphatic vessels of the trunk and digestive viscera travel with the deep arteries Major lymphatic trunks include: lumbar, bronchomediastinal, subclavian, jugular trunks, and the single intestinal trunk There are two major ducts, right lymphatic duct and thoracic duct, where the lymph delivers to one of them: : thoracic duct The right lymphatic duct drains from right arm, right side of head and thorax The thoracic ducts drains from most of the body Lymph vessels are thin walled, and the larger vessels have valves Small organs, intimately, associated with lymphatic vessels are most commonly known as lymph nodes Lymph nodes consist of the outer cortex and the inner medulla Outer Cortex: contains packed lymphocytes arranged in mass called follicles (lymphatic nodules) These include T-cells, B-cells, and macrophages Inner Medulla: contains loosely arranged medullar cords These include macrophages and plasma cells Lymph nodes help protect the body by removing foreign material such as bacteria and tumor cells from lymphatic stream The result of the trapping function of the nodes are swollen nodes during an active infection Other lymphoid organs: 1. Tonsils - consists of multiple, large lymphatic nodules covered in the mucosa There are four different types of tonsils: pharyngeal, palatine, lingual, and tubal. Pharyngeal (adenoids): in the posterior wall of the nasopharynx Paired Palatine: lie between the pharyngopalatine and glossopalatine Paired Lingua: at the base of the tongue Tubal: tiny, surround the opening of the auditory tubules into the pharynx Function of tonsils is to protect against invasion of foreign substances that are inhaled or indigested; they also participate in immune response 2. Spleen - a blood-rich organ that is located in the left side of the abdominal cavity Consists of lobules of splenic pulp (red pulp that is composed of venous sinuses and splenic cords) and white pulp (of packed lymphocytes) Another name for venous sinuses is splenic sinusoids The large splenic artery and vein enter and exit through the hilium NO lymph filtration action 7 of 22 Lensch Functions are: Filters the blood Destroy the worn-out RBC Return His to the liver Source of lymphocytes and monocytes Largest of the lymphatic organs 3.The thymus is a bilobed structure that is surrounded by connective tissue It is a lymphoid and endocrine organ Thymosin => lymphocyte => T-cells Prominent in new bones Increased during childhood Decreased activity, growth stop with age Outer = cortex: tightly packed lymphocytes Inner = medulla: mostly epithelial cells Collection of small lymphoid tissues, which resemble tonsils, and are found in the wall of the small intestine are known as peyer's patches Their function is to capture and destroy bacteria Chapter 21 The Immune System: Innate and Adaptive Body Defenses There are two intrinsic defense systems: The Innate (nonspecific) Defense System - always prepared, responding within minutes to protect the body from all foreign substances; warding off pathogens or harmful/disease-causing microorganisms This system has two barricades 1. First Line of Defense - external body membranes - surface barriers including skin, mucous membranes, and secretions of skin and mucous membranes Provide a variety of protective chemicals including: Acid - acid mantle Enzymes - lysozyme --> destroys bacteria Mucin - mucin --> forms thick, sticky mucus that lines the digestive and respiratory passageways 8 of 22 Lensch Defensins - defensins --> broad-spectrum antimicrobial peptides Other Chemicals - dermcidin --> in eccrine sweat are toxic to bacteria 2. Second Line of Defense - called into action whenever the first line has been penetrated. Relies on internal defenses such as: phagocytic white blood cells, natural killer cells, inflammatory response, antimicrobial proteins, and fever. 3 Antimicrobial Substances: 1. Transferrins - an iron binding protein => inhibits bacterial growth by reducing the amount of available iron 2. Interferons - group of proteins produced by lymphocytes, macrophages, and fibroblasts in response to the presence of viruses => helps to inhibit viral replication 3. Complements - group of 20 inactive proteins in the blood plasma and cell membrane where they enhance certain immune, allergic, and inflammatory reactions (An example of a plasma protein is C 3. It's a major non- specific mechanism. The hallmark is inflammation Phagocytosis - confront pathogens that get through the skin or mucosae into the underlying connective tissue The most abundant type of WBC => neutrophil Events of phagocytosis: 1. A phagocyte adheres to pathogens 2. Endocytosis (Ingestions) 3. Lysosome fuses with the phagocytic vesicle, thus forming a phagolysosome 4. Lysosomal enzymes digest the particles (microbe) leaving a residual body. 5. Exocytosis of the vesicle removes indigestible and residual material The Adaptive (specific) Defense System - attacks particular foreign substances Provides the third line of defense (lymphocytes) which takes more time to mount than the innate defense response Humoral Immunity (Antibody-mediated) --> B-cells, plasma cell, antibodies B-cells transform into plasma cells, which synthesize and secrete specific protein called antibody (Abs) or 9 of 22 Lensch immunoglobulins. Antibodies bind to and deactivate particular antigens A B-cell response usually begins when some antigen-bearing agents are phagocytized by macrophages and others are combined with B-cell receptors T-helper cells activate => interact with B-cell => release lymphokines => stimulate B-cell to proliferate rapidly => clones Newly formed clones (plasma cells) secrete antibodies => form antigen-antibody complex => inactivate antigen => (4 mechanisms) phagocytized => primary immune response 4 Mechanisms of Antibody Action: 1. Neutralization => makes dangerous parts of bacterial exotoxins; viruses 2. Agglutination => cell-bound antigens Enhances => phagocytosis 3. Precipitation => soluble antigens 4. Complement Leads to => cell lysis (MAC) Enhances => phagocytosis and inflammation Other clone members become memory B-cells which are capable of mounting a rapid attack against the same antigen in the future => secondary immune response Cellular Immunity (Cell-mediated) --> T-cells The antigens are derived from fungi, virus, infected cells, parasites and intracellular bacteria This process involves: C8 + T8-cell proliferation into "killer T- cells" (cytotoxic) => attack antigens What is an antigen? => specific markers on cell surfaces; capable of exciting our immune system and provoking an immune response T-cells responds only to antigens B-cells responds mostly all of the above Haptens have the exciting ability but do not provoke immune response Epitopes (antigenic determinants) are the specific portions of antigen molecules that triggers immune response Lymphocytes (T-cells and B-cells) develop from stem cell in red bone marrow. During differentiation, one reaches the thymus gland and becomes differentiated --> called T-lymphocytes (Thymus-derived lymphocytes or T-cells) 10 of 22 Lensch T-cells exit the thymus gland as either: TH <= 4 - C4 + or CD8+ T8(TC) T-cells are 70%-80% of lymphocytes Lymphocytes are released from the bone marrow and do not process into the thymus gland, but another part of the body => unknown => differentiate into B-lymphocytes (B-cells) Immunity (Specific) Resistance - a resistance to specific foreign agents, such as pathogens, or to the toxins by releasing or producing specific lymphocyte or antibody There are three important aspects of immune response: 1. ANTIGEN SPECIFIC: It recognizes and acts against particular pathogen or foreign substances 2. SYSTEMIC: Immunity is not restricted to the initial infection site, but is systematic 3. HAS MEMORY: It recognizes and mounts even stronger attacks on previously encountered/same pathogens Inflammatory Chemicals: Histamine => granules of mast cells and basophils => promotes vasodilation of local arterioles, increases permeability of local capillaries, promoting formation of exudate => chemotaxis Summary of Innate Body Defenses: First Line of Defense: Surface Membrane Barriers Intact Skin Epidermis --> forms mechanical barrier Acid mantle of skin Keratin Intact Mucous Membranes --> forms mechanical barrier Mucus Nasal hairs => filter and trap microorganisms Cilia Gastric juice => contains concentrated hydrochloric acid Acid mantle of vagina Lacrimal secretion (tears); saliva => contains lysozome (an enzyme that destroys microorganisms) Urine => normally acid pH inhibits bacterial growth 11 of 22 Lensch Second Line of Defense: Innate Cellular and Chemical Defenses Phagocytes --> engulf and destroys Natural killer (NK) cell --> promote cell suicide (apoptosis) by directly attacking virus-infected or cancerous body cells Inflammatory Response Antimicrobial Proteins: Interferons => small proteins released by virus-infected cells and certain lymphocytes, act as chemical messengers to protect uninfected tissue cells fro viral take over, mobilize immune system Complement => a group of bloodborne proteins that lyse microorganisms (when activated), enhance phagocytosis by opsonization, and intensify inflammatory and other immune responses Fever --> high body temperature inhibits microbes from multiplying Activation of Complement Proteins 1. Opsonization --> enhancing phagocytosis of antigens 2. Chemotaxis --> attracting macrophages and neutrophils 3. Lysis --> MAC (Membrane Attack Complex) rupturing membranes of foreign cells 4. Clumping of antigen-bearing agents 5. Altering the molecular structure of viruses 6. Causes inflammation (histamine) Antibody Structure There are two of each: heavy chain (400 amino acids) and light chain (200 amino acids) Immunoglobulin Classes IgM (pentamer) => 5%-10% of circulating antibodies First immunoglobulin class secreted by plasma cells during the primary response Readily fixes and activates complement IgA (dimer) => 10%-15% of circulating antibodies Referred to as secretory IgA, it is found in body secretions like saliva, sweat, intestinal juice, and milk Protects mucosal barriers 12 of 22 Lensch IgD (monomer) => 1 %of circulating antibodies Functions as a B-cell antigen receptor As does IgM IgG (monomer) => 75%-85% of circulating antibodies Readily only fixes the complement Protects against bacteria, viruses, and toxins circulating in blood and lymph Crosses the placenta and confers passive immunity from the mother to the fetus IgE (monomer) => 1% Involves in allergies Triggers cells to release histamines that mediate inflammation and an allergic reaction Secreted by plasma cells in the skin, mucosae of the gastrointestinal and respiratory tracts, as well as the tonsils Levels rise during severe allergic attacks Mechanism of Target Cell Killing by TCCells (Cytotoxic T-Cells) Cytotoxic T cells are the only T cells that can directly attack and kill other cells Their main targets are virus-infected cell, but they also attack tissue cells infected by certain intracellular bacteria or parasites Steps of cell killing: 7. T Cdentifies foreign antigens on MHC I proteins and binds tightly to target cell 8. T Celeases perforin and granzyme molecules from its granules by exocytosis 9. Perforin molecules insert into the target cell membrane, polymerize, and form transmembrane pores (cylindrical holes) similar to those produced by complement activation 10. Granzymes enter the target cell via pores. Once inside, granzymes activate enzymes that trigger apoptosis 11. The T Cetaches and searches for another prey There are two major mechanisms: One involves perforins and granzymes The other involves binding to a specific membrane receptor on the target cell to undergo apoptosis Cells and Molecules of the Adaptive Immune Response Cells B Cell => induced to replicate by antigen binding; its progeny, or clone members, form plasma cells and memory cells 13 of 22 Lensch Plasma Cell => "antibody-producing machine;" produces huge numbers of antibodies (immunoglobulins) with the same antigen specificity Helper T Cell HT ) => stimulates production of cytotoxic T cells and plasma cells Regulatory T Cell Reg) => slows or stops activity of immune system Memory Cell => descendant of activated B cell or any class of T cell; may exist in body for years after and can respond quickly if it encounters with same antigen (cause secondary immune response) Antigen-Presenting Cell (APC) => any of several cell types that engulfs and digests antigens that it encounters Molecules Antigen => substance capable of provoking a(n) immune response Antibody (immunoglobulin, Ig) => protein produced by B cell or by plasma cell Perforins, granzymes => released by T cells, perforins create large pores in the target cell's membrane Complement (non-specific defense) => group of 20 bloodborne proteins activated after binding to antibody-covered antigens; enhances inflammatory response and lyses some microorganisms Cytokines => small proteins that act as chemical messengers between various parts of the immune system Chapter 22 The Respiratory System Principal Organs of the Respiratory System Nose => produces mucus; filters, warms, and moistens incoming air; resonance chamber for speech Paranasal Sinuses Pharynx = houses tonsils; passageway for air and food; facilitates exposure of immune system to inhaled antigens Larynx => houses vocal folds (true vocal cords); prevents food from entering lower respiratory tract; voice production Trachea => cleans, warms, and moistens incoming air Bronchial Tree (B.P.) => air passageways connecting trachea with alveoli; cleans, warms, and moistens incoming air Alveoli => produces surfactant; main sites of gas exchange; reduces surface tension; helps prevent lung collapse 14 of 22 Lensch Lungs Pleurae => produce lubricating fluid and compartmentalize lungs Larynx Epiglottis Vestibular fold (FALSE vocal cord) Vocal fold (TRUE vocal cord) Tracheal cartilages Tracheal Wall 12. Mucosa 13. Pseudostratified ciliated columnar epithelium 14. Lamina propria (connective tissue) 15. Submucosa 16. Seromucous gland in submucosa 17. Hyaline Cartilage 18. Adventitia Conducting Zone Passages Superior and Inferior lobe of Rt and Lt lungs Horizontal fissure Middle lobe of Rt and Lt lungs Oblique fissure Carina Bronchial Tree (B.T.) Left main (primary) bronchus ↓ Lobar (secondary) bronchus ↓ Segmental (tertiary) bronchus ↓ 15 of 22 Lensch Terminal Respiratory Zone Structures Terminal Bronchiole Respiratory Bronchioles Alveolar Duct Alveoli Alveolar Sac Changes in Thoracic Volume and Sequence of Events During Inspiration and Expiration Inspiration: => Inspiratory muscles contract (diaphragm descends; rib cage rises) => Thoracic cavity volume increases => Lungs are stretched; intrapulmonary volume increases => Intrapulmonary pressure drops (to –1 mmHg) => Air (gases) flows into lungs down its pressure gradient until intrapulmonary pressure is 0 (equal to atmospheric pressure) Side Notes: Ribs are elevated and sternum flares as external intercostals contract (3 mmHg) Diaphragm moves inferiorly during contraction Expiration: => Inspiratory muscles relax (diaphragm rises; rib cage descends due to recoil of costal cartilages) => Thoracic cavity volume decreases => Elastic lungs recoil passively; intrapulmonary volume decreases => Intrapulmonary pressure rises (to +1 mmHg) => Air (gases) flows out of lungs down its pressure gradient until intrapulmonary pressure is 0 Side Notes: 16 of 22 Lensch Ribs and sternum are depressed as external intercostals relax Diaphragm moves superiorly as it relaxes Volume (L) of breath => 0.5 L in 4 seconds Respiratory Volumes Volumes Average Male Description Tidal Volume (TV) 500 mL Amount of air inhaled or exhaled with each breath under resting Inspiratory Reserve Volume 3100 mL Amount of air that can be (IRV) forcefully inhaled after normal tidal volume inspiration Expiratory Reserve Volume 1200 mL Amount of air that can be (ERV) forcefully exhaled after a normal tidal volume expiration Residual Volume (RV) 1200 mL Amount of air remaining in the lungs after a forced expression Respiratory Capacities Volumes Average Male Description Total Lung Capacity (TLC) 6000 mL Maximum amount of air contained in lungs after a maximum inspiratory effort Vital Capacity (VC) 4800 mL Maximum amountof air that can be expired after a maximum inspiratory effort Inspiratory Capacity (IC) 3600 mL Maximum amount of air that can be inspiredafter a normal tidal volume expiration Functional Residual Capacity 2400 mL Volume of air remaining in the (FRC) lungs after a normal tidal volume expiration Partial Pressure Gradients Promoting Gas Movements in the Body 17 of 22 Lensch 18 of 22 Lensch Pathogenesis of COPD Tobacco Smoke Air Pollution Acidosis and Alkalosis Condition Definition Respiratory Acidosis Increased pCO (2bove 45 mmHg) and decreased pH (below 7.35) if there is no compensation Respiratory Alkalosis Decreased pCO (b2low 35 mmHg) and increased pH (above 7.45) if there is no compensation Metabolic Acidosis Decreased bicarbonate (below 22 mEq/liter) and decreased pH (below 7.35) if there is no compensation Metabolic Alkalosis Increased bicarbonate (above 26 mEq/liter) and increased pH (above 7.45) if there is no compensation Lobes of lungs are divided into => bronchopulmonary segments in which segmental broncht conducts air to the alveolar duct; opening hole into the alveoli: --> Millions of alveoli provide the surface area for gas exchange **Each bronchopulmonary segments consist of lobules, which contain: Lymphatics Arterioles (pulmonary) Venules (pulmonary) Terminal Bronchioles Respiratory Bronchioles Alveolar Ducts Alveolar Sacs Alveoli ↑ PO =2 ↑ O sat2ration ↑ pH => ↑ O sa2uration 19 of 22 Lensch ↓ PCO2=> ↑ O2saturation ↓ Temperature => ↑2O saturation Nose Nasal cavities are lined with mucosa, which warms, filters, and moistens incoming air ** Paranasal sinuses and nasolacrimal ducts drain into nasal cavities Nose ↓ Nasal Cavities and Paranasal Sinuses ↓ Pharynx <= Adenoids <= Tonsils ↓ Larynx <= Epiglottis ↓ Trachea ↓ Bronchi (Pri., Sec., Ter., Ter.) ↓ Resp. Bronchioles ↓ <= OD Alveoli ↓ Lung Capillaries (bloodstream) 20 of 22 Lensch Key: Upper Respiratory System Lower Respiratory System Pharynx (throat) Mucosa-lined, muscular tube with three regions: 1. Nasopharynx 2. Oropharynx 3. Laryngopharynx Nasopharynx functions in respiration only; the others serve both respiratory and digestive system functions Pharynx contains tonsil Larynx (voice box) Larynx contains vocal cords => produce sounds used in speech Trachea (wind pipe) C-shaped cartilage (Hyaline cartilage) rings, that keep the trachea potent Pulmonary Ventilation (Breathing) 2 Phases (in cycle): 19. Inspiration/Inhalation (breathing in) 20. Expiration/Exhalation (breathing out) Inspiration When diaphragm is stimulated (contracted by phrenic nerve) => move downward 21 of 22 Lensch => ↑ in thoracic cavity --> ↑ in thoracic volume => ↓ the pressure in the alveoli (about 1 mmHg) --> air is forced into airways => Intra --> pulmonary pressure While diaphragm is contracting and moving downward ** External intercostal muscles between the ribs --> contract => Raises the ribs and elevation of the sternum => ↑ further size (volume) of thoracic cavity => ↓ intra pleural pressure (3 mmHg) => Expansion of lungs --> ↓ decreases alveolar pressure => air move into by greater atmospheric pressure ** During forced inspiration, sternocleidomastoids, scalenes, and pectoralis minor muscles are also used 22 of 22
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