Respiratory System Anatomy & Physiology PDF

Anatomy and Physiology, 1e Chapter 22: The Respiratory System Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May n...

Anatomy and Physiology, 1e Chapter 22: The Respiratory System Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 1  Icebreaker Breathing is a daily activity that we can often take for granted. The human body requires oxygen to produce energy in the form of ATP. How does the human body acquire the oxygen that cells need? How does it eliminate carbon dioxide? What role does the circulatory system play in aiding gas exchange? In this chapter, we will discuss the respiratory system. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 2 Functions and Anatomy of the Respiratory System Section 22.1 Learning Objectives 22.1.1–22.1.16 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 3  Functions of the Respiratory System Functions of the respiratory system include: 1. Gas exchange 2. Speech 3. Immune protection 4. pH homeostasis 5. Olfaction Two physiological divisions of the respiratory system: Conducting zone—components air simply travels through Respiratory zone—areas where gases are exchanged Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 4  Conducting Zone (Figure 22.1) Provides passageways for air to reach respiratory zone Helps to filter, warm, and humidify incoming air Consists of: External nose, nasal cavity, pharynx, larynx, trachea, and several airways within the lungs Upper respiratory tract = structures found in the head and neck Lower respiratory tract = structures found in thorax Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 5  The Nose (Figure 22.2) Major entrance and exit of air for respiratory system External nose is visible on surface of face Root = region between eyebrows Bridge connects root to rest of nose Formed mainly by nasal bones Dorsum nasi = length of nose Apex = tip of nose Alar cartilage support and help form nostrils (openings) Philtrum = connects apex to upper lip Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 6  Nasal Cavity (Figure 22.3) Space within skull that communicates with external nose Divided by nasal septum Formed by septal cartilage, perpendicular plate of ethmoid bone, and vomer bone Conchae project into cavity to help warm and moisten inhaled air Meatuses are between conchae Communicates with paranasal sinuses Help lighten the skull and allow for resonance of voice Air moves from nasal cavity into pharynx via internal nares Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 7  Respiratory Epithelium (Figure 22.4) Nares and anterior nasal cavity lined by mucous membranes Olfactory epithelium detects smell in nasal cavity Conchae, meatuses, and sinuses lined by respiratory epithelium Pseudostratified columnar epithelium Goblet cells secrete mucus to trap dirt, debris, and pathogens Cilia sweep mucus toward throat Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 8  Pharynx (Figure 22.5) Anatomical term for the throat Funnel-like tube for passage of air and food Divided into: Nasopharynx Contains pharyngeal tonsil and openings of auditory tubes Oropharynx Contains palatine and lingual tonsils Laryngopharynx At inferior border, transports food into esophagus and air into larynx Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 9  Larynx (Figure 22.6) Entrance to lower respiratory tract Also known as “voice box” Composed cartilage Thyroid cartilage is largest cartilage; contains thyroid prominence Epiglottis protects airway during swallowing Cricoid cartilage forms a ring Paired arytenoid, corniculate, and cuneiform cartilages Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 10  The Vocal Cords (Figure 22.7) Glottis = space below epiglottis Vestibular folds are more membranous Very sensitive to particles in airway Also known as false vocal cords Vocal folds vibrate to produce sound Also known as vocal cords or true vocal cords Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 11  Laryngeal Cartilages (Figure 22.8) Vocal folds are anchored to thyroid and arytenoid cartilages Arytenoid cartilages rotate on cricoid cartilage to change position of vocal folds Open = breathing position Closed = phonation (speech) Speech is produced as air is forced past the vocal folds, causing them to vibrate Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 12  Vocal Pitch and Tone (Figure 22.9) Vocal pitch and tone depend on the structure of the vocal folds and larynx Anatomical differences lead to different pitches and tones Longer vocal folds produce deeper, lower- pitched sounds Shorter vocal folds produce higher- pitched sounds Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 13  Trachea (Figure 22.10) Extends from larynx into mediastinum Also known as the “windpipe” Reinforced by C-shaped tracheal rings made of hyaline cartilage Trachealis muscle found posteriorly Allows for expansion of esophagus Lined by pseudostratified columnar epithelium Divides at the carina inferiorly Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 14  Trachealis Muscle (Figure 22.11) Trachea is positioned anterior to esophagus Trachealis muscle allows: Expansion of trachea during inhalation Expansion of esophagus during swallowing Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 15  Bronchial Tree (Figure 22.12) 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 Lined by pseudostratified ciliated columnar epithelium Supported by rings of cartilage Enter lungs at hilum Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 16  Bronchioles (Figure 22.12) Bronchi eventually branch into bronchioles Smallest terminal bronchioles (respiratory bronchioles) branch and allow air to enter respiratory zone Bronchioles have smooth muscle to support their walls, yet no cartilage Muscle allows for bronchodilation or bronchoconstriction Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 17  Respiratory Zone (Figure 22.14) Pulmonary capillaries allow gas exchange between the lungs and blood Consists of respiratory bronchioles, alveolar ducts, and alveolar sacs made of individual alveoli Respiratory epithelium replaced by simple squamous epithelium Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 18  Alveoli (Figure 22.14) Thin walls allow gas exchange Type I alveolar cells are simple squamous epithelium Type II alveolar cells secrete surfactant to reduce surface tension Alveolar macrophages protect against infection Alveolar pores connect neighboring alveoli Helps maintain air pressure within lung Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 19  Gas Exchange Across the Respiratory Membrane Respiratory membrane is a thin barrier to allow gas exchange to occur Formed by type I alveolar cells, a basement membrane, and endothelial cells of pulmonary capillaries Oxygen diffuses from alveolus into blood Carbon dioxide diffuses from blood into alveolus Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 20 Anatomy of the Lungs (1 of 2) (Figure 22.16) Surrounded by pleural membranes Pleural cavity between the two layers contains pleural fluid Reduces friction due to movement of lungs Aids in expansion of lungs during inhalation Apex = superior point of lung Base = broad, inferior bottom of lung Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 21 Anatomy of the Lungs (2 of 2) (Figure 22.17) Right lung has three lobes Superior, middle, and inferior Separated by horizontal and oblique fissures Left lung has two lobes Separated by oblique fissure Contains cardiac notch Indentation for apex of heart Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 22  Hilum of the Lung (Figure 22.13) Hilum is an anatomical structure where pulmonary arteries, pulmonary veins, nerves, lymphatics, and primary bronchi enter or leave each lung Pulmonary arteries bring deoxygenated blood to the lungs Pulmonary capillaries allow gas exchange to take place Pulmonary veins carry oxygenated blood to heart Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 23  Matching Activity 1 Match the 1. Trachea A. Conducting zone structure to the correct area of the 2. Pharynx B. Respiratory zone respiratory 3. Alveolus system. 4. Larynx 5. Bronchi 6. Alveolar duct Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 24  Matching Activity 1 Answer Match the 1. Trachea—A A. Conducting zone structure to the correct area of the 2. Pharynx—A B. Respiratory zone respiratory 3. Alveolus—B system. 4. Larynx—A 5. Bronchi—A 6. Alveolar duct—B Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 25  Knowledge Check Activity 1 Which section of the pharynx contains the palatine tonsils? A. Oropharynx B. Laryngopharynx C. Nasopharynx Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 26  Knowledge Check Activity 1 Answer Which section of the pharynx contains the palatine tonsils? A. Oropharynx Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 27  Think, Pair, Share Activity 1 Larger airways in the lungs contain cartilage similar to C-shaped tracheal rings found in the trachea. What are some advantages of having cartilage in large airways? Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 28  Think, Pair, Share Activity 1 Answer Larger airways in the lungs contain cartilage similar to C-shaped tracheal rings found in the trachea. What are some advantages of having cartilage in large airways? If an airway contains cartilage in the wall, the cartilage helps the airway remain patent or open. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 29 The Process of Breathing Section 22.2 Learning Objectives 22.2.1–21.2.9 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 30  Processes of the Respiratory System The respiratory system delivers oxygen to the cells of the body for use in aerobic respiration Aerobic respiration allows the body to produce large amounts of ATP To deliver this oxygen, the respiratory system carries out the following processes: Ventilation Gas exchange across the respiratory membrane Gas transport Gas exchange between the blood and tissues Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 31 Pressures of the Lungs (Figure 22.21) Atmospheric pressure = generated by the external air Constant 760 mm Hg at sea level Intrapulmonary pressure = pressure within alveoli Intrapleural pressure = pressure within pleural cavity Transpulmonary pressure = difference between intrapleural and intrapulmonary pressures Determines size of lungs Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 32  Ventilation The movement of air into and out of the lungs Divided into inhalation (inspiration) and exhalation (expiration) Inhalation—air enters lungs Exhalation—air exits lungs Driven by pressure gradient between atmospheric pressure (Patm) and intrapulmonary pressure (Ppul) inside alveoli Air always moves from higher toward lower pressure Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 33  Bulk Flow and Pressure Gradients (Figure 22.18) Air moves from areas of higher pressure to areas of lower pressure If atmospheric pressure is greater than intrapulmonary pressure, inhalation occurs If atmospheric pressure is less than intrapulmonary pressure, exhalation occurs Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 34  Boyle’s Law (Figure 22.20) For gases, pressure is caused by collisions with the wall of a container More collisions = higher pressure Fewer collisions = lower pressure Intrapulmonary pressure changes according to Boyle’s Law Pressure inversely related to volume For ventilation to occur, the intrapulmonary pressure must change Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 35  Inhalation (Figure 22.19) Occurs when Ppul is less then Patm Ppul changes according to Boyle’s law Increasing thoracic volume leads to decrease in Ppul Inhalation requires muscular contraction Normal, quiet inhalation—diaphragm and external intercostals contract Deep inhalation—requires additional contraction of scalene muscles, sternocleidomastoid, and pectoralis minor Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 36  Exhalation (Figure 22.19) Occurs when Ppul is greater than Patm Does not always require muscular contraction Normal, quiet exhalation—depends on recoil of lungs, chest wall, and diaphragm Forceful exhalation—requires muscular contraction Muscle of the abdominal wall (internal and external obliques, rectus and transversus abdominis, and internal intercostals) Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 37  Factors Affecting Ventilation Various characteristics of the lungs can influence the effort required to ventilate Airway resistance Mainly influenced by the diameter of the airways Controlled by bronchoconstriction and bronchodilation Elasticity of the lungs Surface tension of alveoli Caused by water molecules Reduced by surfactant Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 38  The Pleurae (Figure 22.22) 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 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 39  Application: Pneumothorax (Figure 22.23) Intrapleural pressure (Pip) must remain below intrapulmonary pressure to prevent lung collapse (atelectasis, due to pneumothorax) If air enters pleural cavity, it disrupts the cohesion between the pleurae leading to lung collapse, difficulty breathing Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 40  Think, Pair, Share Activity 2 There are several factors that affect ventilation. What change would have to be made to each factor to make the work of ventilation easier? What change to each factor would make the work of ventilation more difficult? Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 41  Think, Pair, Share Activity 2 Answer There are several factors that affect ventilation. What change would have to be made to each factor to make the work of ventilation easier? What change to each factor would make the work of ventilation more difficult? The work of ventilation is easier if airway resistance is low, the lungs are highly elastic (compliant), and the surface tension of the alveoli is low. The work of ventilation is more difficult if airway resistance increases, the lungs lose their elasticity, or if the surface tension in the alveoli increases. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 42  Breakout Group Activity 1 In your group, you will draw two diagrams. In the first diagram, illustrate the process of inhalation. In the second diagram, illustrate the process of exhalation. Make sure to label the direction of air movement, the value of the pressures involved, and the muscles (if any) involved. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 43 Respiratory Volumes and Capacities Section 22.3 Learning Objectives 22.3.1–22.3.4 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 44  Respiratory Volumes Amounts of air moved by the lungs at different points in the respiratory cycle Measured using a spirometer Can be used to evaluate how well lungs are ventilated Four lung volumes: 1. Tidal Volume (TV)—the amount of air that enters or exits the lungs during a normal, quiet breath 2. Inspiratory reserve volume (IRV)—additional air inhaled during a deep inhalation 3. Expiratory reserve volume (ERV)—additional air exhaled during a forceful exhalation 4. Residual volume (RV)—air remaining in lungs after maximal exhalation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 45  Respiratory Capacities Combinations of two or more volumes Amount of air in lungs during a given time period Total lung capacity (TLC)—total amount of air lungs can hold Vital capacity (VC)—total amount of air a person can move into or out of the lungs during a breath Inspiratory capacity (IC)—maximal amount of air inhaled past normal tidal expiration Functional residual capacity (FRC)—amount of air remaining in lungs after normal exhalation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 46 Lung Volumes and Capacities (Figure 22.24) Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 47  Dead Space Anatomical dead space = air present in airways that never reaches respiratory zone Alveolar dead space = air within alveoli that do not function Alveoli may be affected by disease or abnormal blood flow Air within alveoli does not participate in gas exchange Total dead space = combination of anatomical and alveolar dead space All the air in the respiratory system not being used for gas exchange Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 48  Minute Ventilation Minute ventilation (MV) = total volume of air that enters lungs per minute Equation: MV = respiratory rate (RR) x tidal volume (TV) Alveolar ventilation = amount of air that reaches the respiratory membrane per minute Calculated by subtracting anatomical dead space from minute ventilation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 49  Think, Pair, Share Activity 3 Emphysema is a disease that decreases the elasticity of the lungs. What changes would you expect to see in the lung volumes and capacities of a patient that has emphysema? Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 50  Think, Pair, Share Activity 3 Answer Emphysema is a disease that decreases the elasticity of the lungs. What changes would you expect to see in the lung volumes and capacities of a patient that has emphysema? Lung volumes and capacities decrease with emphysema due to a loss of elasticity in the lungs. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 51  Knowledge Check Activity 2 Which of the following lung volumes or capacities remains in the lungs after a maximal exhalation? A. Functional residual capacity B. Tidal volume C. Expiratory reserve volume D. Residual volume Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 52  Knowledge Check Activity 2 Answer Which of the following lung volumes or capacities remains in the lungs after a maximal exhalation? D. Residual volume Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 53  Gas Exchange Section 22.4 Learning Objectives 22.4.1–22.4.8 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 54  Gas Laws and Diffusion Gas exchange occurs by simple diffusion Two gas laws govern the diffusion of gases Dalton’s Law—each gas in a mixture of gases exerts its own partial pressure Henry’s Law—diffusion depends on partial pressure gradient and solubility of gas in a liquid Gases diffuse from areas of higher partial pressure toward lower partial pressure Partial pressure gradient and solubility of gases influence diffusion Other factors, like surface area and respiratory membrane thickness, can also influence diffusion within lungs Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 55  Dalton’s Law (Figure 22.25) Describes behavior of gases in a mixture States that each gas in a mixture exerts its own pressure independent of other gases Total pressure is the sum of all the partial pressures within a container Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 56  Partial Pressures of Gases within Air (Table 22.1) Partial pressure of gases in atmospheric air Gases will diffuse from areas of higher partial pressure to areas of lower partial pressure Greater partial pressure difference = faster movement of gases Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 57  Henry’s Law (Figure 22.26) Describes behavior of gases when in contact with a liquid Amount of a gas dissolved in a liquid depends on: The partial pressure gradient The solubility of the gas in the liquid Oxygen is minimally soluble in plasma Carbon dioxide is more soluble in plasma Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 58  Gas Exchange in the Lungs (Figure 22.27) Oxygen diffuses from alveoli into pulmonary capillaries Partial pressure of oxygen in alveoli is ~100 mmHg Partial pressure of oxygen in pulmonary capillaries is ~40 mmHg Carbon dioxide diffuses from pulmonary capillaries into alveoli to be exhaled Partial pressure of carbon dioxide in alveoli is ~40 mmHg Partial pressure of carbon dioxide in pulmonary capillaries is ~45 mmHg Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 59  Factors That Influence Gas Exchange Available surface area for diffusion Determined by number of functional alveoli Decreases in conditions like emphysema or pneumothorax Size of partial pressure gradient Smaller partial pressure gradient decreases diffusion Occurs at higher altitudes where partial pressure of oxygen is lower Can lead to high altitude syndrome Thickness of respiratory membrane Scar tissue, fibrosis, or mucus may increase thickness and decrease diffusion of gas across the membrane Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 60  Ventilation and Perfusion Ventilation—movement of air into and out of lungs Perfusion—blood flow in pulmonary capillaries Ventilation-perfusion coupling directs blood flow toward capillaries associated with alveoli that are well ventilated Controlled by constriction of arterioles Influenced by factors such as gravity, pulmonary disease, carbon dioxide, oxygen, and pH Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 61  Gas Exchange at the Tissues (Figure 22.28) Oxygen diffuses from blood and into tissues Partial pressure of oxygen in blood is ~100 mmHg Partial pressure of oxygen in tissues is ~40 mmHg Carbon dioxide produced by cellular respiration diffuses from tissues and into blood Partial pressure of carbon dioxide in blood is ~40 mmHg Partial pressure of carbon dioxide in tissues is ~45 mmHg Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 62  Application: Asthma Chronic disease characterized by inflammation, edema, and constriction of airways Restricts movement of air toward respiratory zone Symptoms include coughing, wheezing, shortness of breath, and chest tightness May be treated with bronchodilators (to increase diameter) and steroids to reduce inflammation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 63  Think, Pair, Share Activity 4 At higher altitudes the diffusion of oxygen into blood slows down. Using Henry’s law, explain why diffusion of gases slows at higher altitudes. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 64  Think, Pair, Share Activity 4 Answer At higher altitudes the diffusion of oxygen into blood slows down. Using Henry’s law, explain why diffusion of gases slows at higher altitudes. At higher altitudes, the partial pressure of oxygen decreases. This decreases the partial pressure gradient that drives the diffusion of oxygen into blood, leading to slower diffusion. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 65  Breakout Group Activity 2 The atmosphere contains other gases besides oxygen and carbon dioxide. In your group research the other gases that are present. Why aren’t these gases found in high amounts in our blood? Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 66  Breakout Group Activity 2 Answer The atmosphere contains other gases besides oxygen and carbon dioxide. In your group research the other gases that are present. Why aren’t these gases found in high amounts in our blood? Other gases found in the atmosphere include nitrogen, carbon monoxide, and water vapor. These gases aren’t found in high amounts in our blood because they are not readily soluble in blood. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 67  Transport of Gasses Section 22.5 Learning Objectives 22.5.1–22.5.5 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 68  Oxygen Transport in Blood (Figure 22.29) Oxygen transported in blood by two means: Bound to hemoglobin as oxyhemoglobin (~98.5%) Dissolved oxygen accounts for (~1.5%) Hemoglobin reversibly binds oxygen in order to pick it up in the lungs and drop it off at the tissue level Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 69  Pulse Oximeters (Figure 22.30) Device used to measure the percent of hemoglobin molecules saturated with oxygen If all four heme groups are bound to oxygen, hemoglobin is called saturated Partially saturated if less than four oxygen molecules bound 95-99% saturation in healthy individuals Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 70  Function of Hemoglobin A mature hemoglobin molecule can bind four molecules of oxygen Four molecules of oxygen bound—fully saturated hemoglobin (100%) Hemoglobin’s affinity for oxygen determines if it will bind or release oxygen High affinity—binding of oxygen Lower affinity—release of oxygen Directly influenced by partial pressure of oxygen Inversely influenced by acidity, heat, and high partial pressure of carbon dioxide All metabolic Elizabeth Co, Anatomy byproducts and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 71  Oxygen-Hemoglobin Dissociation Curve At higher partial pressures of oxygen, hemoglobin’s affinity for oxygen increases Evidenced by 100% saturation at higher pO2 As partial pressure of oxygen decreases, hemoglobin's affinity for oxygen decreases also Evidenced by lower saturation at lower pO2 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 72  Hemoglobin’s Affinity for Oxygen Changes (Figure 22.31) Metabolic byproducts can influence hemoglobin's affinity and shift the oxygen dissociation curve Increased temperature and decreased pH indicate increased metabolism (a shift to the right) A shift to the right decreases affinity and allows more oxygen to be delivered to more metabolically active tissues Indicated by Bohr effect seen on oxygen- dissociation curve Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 73  Fetal Hemoglobin (Figure 22.32) During fetal development, fetal blood and maternal blood do not mix Fetus must get oxygen from maternal blood Fetal hemoglobin has a greater affinity for oxygen Allows fetal hemoglobin to bind oxygen from maternal hemoglobin Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 74  Carbon Dioxide Transport in Blood Carbon dioxide transported in blood by three means: 1. Bicarbonate ions (~70%) Function as buffer in blood to help prevent rapid changes in pH Carbon dioxide has to be converted into bicarbonate ions for transport Bicarbonate ions converted back into carbon dioxide to be exhaled 2. Bound to hemoglobin (~23%) As carbaminohemoglobin 3. Dissolved carbon dioxide (~7%) Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 75  Bicarbonate Buffer Conversion occurs within red blood cells The enzyme carbonic anhydrase (CA) plays a critical role The conversion is represented by two associated reversible reactions: CO2 + H2O ↔ H2 CO3 ↔ H+ + HCO3- Carbonic anhydrase catalyzes the reversible reaction of carbon dioxide and water to produce carbonic acid Bicarbonate ions can buffer the blood when the pH is low by binding excess H+ ions and carbonic acid can donate H+ ions if blood pH is above normal Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 76  Carbon Dioxide in the Blood (Figure 22.33) Majority of carbon dioxide molecules that enter blood enter RBC’s Within RBC, carbonic anhydrase converts carbon dioxide into carbonic acid Carbonic acid dissociates to yield bicarbonate ions Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 77  Matching Activity 2 Match the gas to 1. Carbon dioxide A. Bicarbonate ions its method of transport in blood. 2. Oxygen B. Oxyhemoglobin C. Carbaminohemo globin D. Dissolved in plasma Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 78  Matching Activity 2 Answer Match the gas to 1. Carbon dioxide— A. Bicarbonate ions its method of A, C, D transport in blood. B. Oxyhemoglobin 2. Oxygen—B, D C. Carbaminohemo globin D. Dissolved in plasma Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 79  Think, Pair, Share Activity 5 During a marathon, what do you expect to happen to hemoglobin’s affinity for oxygen? Justify your reasoning using changes in partial pressures, temperature, and pH. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 80  Think, Pair, Share Activity 5 Answer During a marathon, what do you expect to happen to hemoglobin’s affinity for oxygen? Justify your reasoning using changes in partial pressures, temperature, and pH. During a marathon, hemoglobin’s affinity for oxygen should decrease. This is due to the decreased partial pressure of oxygen, increased partial pressure of carbon dioxide, increased temperature, and decreased pH that occurs as the runner uses their muscles. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 81 Respiratory Rate and Control of Ventilation Section 22.6 Learning Objectives 22.6.1–22.6.4 Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 82  Ventilation Control Centers (Figure 22.34) Average respiratory rate of adult is 12 to 18 breaths per minute Controlled primarily by control centers in medulla oblongata Dorsal respiratory group (DRG) maintains constant breathing rhythm Ventral respiratory group (VRG) regulates deep breathing Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 83  Additional Respiratory Control Centers Pontine respiratory group is in the pons Consists of apneustic and pneumotaxic centers Apneustic center stimulates dorsal respiratory group (DRG) to control depth of inspiration Pneumotaxic center inhibits neurons of DRG to prevent over inflation of lungs Leads to exhalation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 84  Breath Rate is Determined by Gases (Figure 22.35) Carbon dioxide is the primary gas that drives respiratory rate Maintains pH of blood (H+ concentration) Central and peripheral chemoreceptors monitor concentrations of CO2 and H+ Increases in CO2 and H+ lead to increased respiratory rate Decreases in CO2 and H+ lead to decreased respiratory rate Oxygen levels influence respiratory rate when they are very low Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 85  Patterns of Breathing Hypoventilation—decrease in rate of ventilation below that which is necessary to maintain normal blood gas concentrations Hyperventilation—increase in rate of ventilation above that which is necessary maintain normal blood gas concentrations Eupnea—normal rate of ventilation; “true breathing” Hyperpnea—increase in rate and depth of ventilation above that of a normal, resting person Apnea—absence of ventilation Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 86  Knowledge Check Activity 3 Control of breathing originates in the: A. Midbrain B. Medulla oblongata C. Cerebral cortex D. Cerebellum Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 87  Knowledge Check Activity 3 Answer Control of breathing originates in the: B. Medulla oblongata Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 88  Matching Activity 3 Match the term to 1. Eupnea A. Absence of the correct breathing definition. 2. Hyperventilation B. Faster than 3. Hypoventilation normal breathing rate 4. Apnea C. Normal breathing rate D. Slower than normal breathing rate Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 89  Matching Activity 3 Answer Match the term to 1. Eupnea—C A. Absence of the correct breathing definition. 2. Hyperventilation —B B. Faster than normal breathing 3. Hypoventilation rate —D C. Normal breathing 4. Apnea—A rate D. Slower than normal breathing rate Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 90  Summary By the end of this chapter, you should be able to: Describe the gross anatomy of the structures associated with the respiratory system. Discuss the functions of the respiratory system and its components. Discuss the how gas exchange occurs. Discuss how oxygen and carbon dioxide are transported in blood. Discuss how respiration is controlled. Elizabeth Co, Anatomy and Physiology, 1st Edition. © 2023 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 91