Companion Guide to Basic Anatomy and Physiology

Companion Guide to Basic Anatomy and Physiology (In development)

Akash Garg M.S., D.C. Spartanburg Community College

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

I. Introduction The respiratory system is responsible for the exchange of gases between the body and the environment. It consists of the upper respiratory tract, which includes the nasal cavity, pharynx, and larynx, and the lower respiratory tract, which includes the trachea, bronchi, bronchioles, and alveoli. The primary function of the respiratory system is to provide oxygen to the body's cells and remove carbon dioxide from the body. II. Anatomy of the Respiratory System A. Upper respiratory tract Nasal cavity The nasal cavity is the first structure air encounters in the respiratory system. It is responsible for filtering, humidifying, and warming the air as it enters the body. The nasal cavity is lined with mucous membrane and cilia, which help trap and remove foreign particles. Pharynx The pharynx is a muscular tube that connects the nasal cavity and mouth to the larynx and esophagus. It is divided into three parts: the nasopharynx, oropharynx, and laryngopharynx. The tonsils, which help fight infection, are located in the pharynx. Larynx The larynx is a structure in the respiratory system that contains the vocal cords. It plays a key role in speech production and also prevents food and liquid from entering the trachea. The epiglottis, a flap of tissue, covers the larynx during swallowing. B. Lower respiratory tract Trachea The trachea, also known as the windpipe, is a tube that connects the larynx to the bronchi. It is lined with mucous membrane and cilia, which help trap and remove foreign particles. The trachea is reinforced with cartilage rings to keep it open. Bronchi The bronchi are two branches of the trachea that enter the lungs. The right bronchus is wider and shorter than the left bronchus. The bronchi are lined with mucous membrane and cilia, which help trap and remove foreign particles. Bronchioles The bronchioles are smaller branches of the bronchi that deliver air to the alveoli. They are surrounded by smooth muscle and can constrict or dilate to regulate airflow.

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

Alveoli The alveoli are small, thin-walled sacs in the lungs where gas exchange occurs. Oxygen diffuses from the alveoli into the blood, while carbon dioxide diffuses from the blood into the alveoli. The alveoli are surrounded by a network of capillaries and are coated with surfactant, which helps to reduce surface tension and prevent them from collapsing. III. Physiology of the Respiratory System A. Mechanics of breathing Breathing is a process that involves two phases: inspiration and expiration. During inspiration, the diaphragm contracts and moves downward, while the external intercostal muscles contract and move the ribs upward and outward. This causes the thoracic cavity to expand and air to flow into the lungs. During expiration, the diaphragm relaxes and moves upward, while the external intercostal muscles relax and move the ribs downward and inward. This causes the thoracic cavity to contract and air to flow out of the lungs. B. Gas exchange in the lungs Gas exchange in the lungs occurs through diffusion. Oxygen diffuses from the alveoli into the blood, while carbon dioxide diffuses from the blood into the alveoli. The diffusion of gases is facilitated by a concentration gradient and the thin walls of the alveoli and capillaries. C. Control of breathing Breathing is controlled by the respiratory center in the medulla oblongata and pons of the brainstem. The respiratory center responds to changes in carbon dioxide levels, oxygen levels, and blood pH to regulate breathing rate and depth. The respiratory center also receives input from chemoreceptors located in the aortic arch and carotid arteries. D. Lung volumes and capacities Lung volumes and capacities are measurements used to assess lung function. Tidal volume is the amount of air that moves in and out of the lungs during normal breathing. Inspiratory reserve volume is the amount of air that can be inhaled beyond the tidal volume. Expiratory reserve volume is the amount of air that can be exhaled beyond the tidal volume. Residual volume is the amount of air that remains in the lungs after a maximal exhalation. Lung capacities are combinations of two or more lung volumes. Inspiratory capacity is the maximum amount of air that can be inhaled after a normal exhalation. Functional residual capacity is the amount of air that remains in the lungs after a normal exhalation. Vital capacity is the maximum amount of air that can be exhaled after a maximal inhalation. Total lung capacity is the sum of all lung volumes. E. Respiratory System Development The respiratory system begins to develop during the embryonic stage and continues to develop throughout childhood. The lungs produce surfactant, a substance that helps keep the alveoli open

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

and prevents them from collapsing. Premature infants may not produce enough surfactant, which can lead to respiratory distress syndrome. IV. Clinical Examination of the Respiratory System The clinical examination of the respiratory system includes inspection, palpation, percussion, and auscultation. Pulmonary function tests, bronchoscopy, chest X-ray, and CT scan may also be used to assess lung function and diagnose respiratory disorders. V. Respiratory Disorders Respiratory disorders can affect any part of the respiratory system and can range from mild to life-threatening. Common respiratory disorders include asthma, chronic obstructive pulmonary disease (COPD), bronchitis, pneumonia, and lung cancer. Treatment may include medication, oxygen therapy, pulmonary rehabilitation, or surgery. VI. Summary and Review The respiratory system is responsible for the exchange of gases between the body and the environment. It consists of the upper and lower respiratory tract, which include the nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli. The mechanics of breathing, gas exchange in the lungs, control of breathing, and lung volumes and capacities are key concepts in respiratory physiology. Respiratory disorders can affect any part of the respiratory system and may require medical intervention. VII. Additional resources Students can access additional resources such as textbooks, online articles, and videos to supplement their understanding of the respiratory system. Please do not forget to visit the Science Resources Shell. Many videos on these topics are already present to help you with this information.

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

Practice Questions Which of the following is the first structure air encounters in the respiratory system? a. Pharynx b. Larynx c. Trachea d. Nasal cavity Answer: d. Nasal cavity Explanation: The nasal cavity is the first structure air encounters in the respiratory system. It is responsible for filtering, humidifying, and warming the air as it enters the body. Which of the following structures contains the vocal cords? a. Larynx b. Trachea c. Bronchi d. Alveoli Answer: a. Larynx Explanation: The larynx is a structure in the respiratory system that contains the vocal cords. It plays a key role in speech production and also prevents food and liquid from entering the trachea. What is the primary function of the respiratory system? a. Removing waste products from the body b. Regulating blood glucose levels c. Providing oxygen to the body's cells d. Controlling body temperature Answer: c. Providing oxygen to the body's cells Explanation: The primary function of the respiratory system is to provide oxygen to the body's cells and remove carbon dioxide from the body.

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

Which of the following lung volumes is the amount of air that remains in the lungs after a maximal exhalation? a. Tidal volume b. Inspiratory reserve volume c. Expiratory reserve volume d. Residual volume Answer: d. Residual volume Explanation: Residual volume is the amount of air that remains in the lungs after a maximal exhalation. It is important for maintaining lung function and preventing lung collapse. What is the process of gas exchange in the lungs called? a. Diffusion b. Filtration c. Osmosis d. Active transport Answer: a. Diffusion Explanation: Gas exchange in the lungs occurs through diffusion. Oxygen diffuses from the alveoli into the blood, while carbon dioxide diffuses from the blood into the alveoli. What is the role of surfactant in the lungs? a. To reduce surface tension and prevent the alveoli from collapsing b. To regulate breathing rate and depth c. To filter foreign particles from the air d. To transport oxygen and carbon dioxide between the lungs and body tissues Answer: a. To reduce surface tension and prevent the alveoli from collapsing Explanation: Surfactant is a substance produced by the lungs that helps to reduce surface tension and prevent the alveoli from collapsing during exhalation. This is important for maintaining proper lung function.

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

Which of the following respiratory disorders is characterized by inflammation of the bronchi? a. Asthma b. Chronic obstructive pulmonary disease (COPD) c. Bronchitis d. Pneumonia Answer: c. Bronchitis Explanation: Bronchitis is a respiratory disorder characterized by inflammation of the bronchi. It can cause coughing, difficulty breathing, and production of mucus. What is the role of the respiratory center in the medulla oblongata and pons of the brainstem? a. To regulate blood glucose levels b. To control body temperature c. To regulate breathing rate and depth d. To transport oxygen and carbon dioxide between the lungs and body tissues Answer: c. To regulate breathing rate and depth Explanation: The respiratory center in the medulla oblongata and pons of the brainstem regulates breathing rate and depth in response to changes in carbon dioxide levels, oxygen levels, and blood pH. What respiratory disorder is characterized by damage to the alveoli? a. Emphysema b. Asthma c. Bronchitis d. Pneumonia Answer: a. Emphysema Explanation: Emphysema is a respiratory disorder characterized by damage to the alveoli. This damage can cause shortness of breath and difficulty breathing.

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

Which of the following structures delivers air to the alveoli? a. Trachea b. Bronchi c. Pharynx d. Larynx Answer: b. Bronchi Explanation: The bronchi are two branches of the trachea that enter the lungs and deliver air to the alveoli. The bronchi are lined with mucous membrane and cilia, which help trap and remove foreign particles. Describe the process of gas exchange in the lungs, including the structures involved and the factors that influence gas diffusion. Answer: Gas exchange in the lungs involves the diffusion of oxygen and carbon dioxide across the respiratory membrane. Oxygen diffuses from the alveoli into the capillaries, while carbon dioxide diffuses from the capillaries into the alveoli. The respiratory membrane is composed of the alveolar wall, capillary wall, and basement membrane. The thin walls of the alveoli and capillaries allow for efficient gas exchange. Factors that influence gas diffusion include the partial pressure of oxygen and carbon dioxide, the surface area of the respiratory membrane, the thickness of the respiratory membrane, and the ventilation-perfusion ratio. Explain how the respiratory system is involved in maintaining acid-base balance in the body. Answer: The respiratory system plays a key role in maintaining acid-base balance in the body by regulating the levels of carbon dioxide in the blood. Carbon dioxide is a waste product of cellular respiration that is transported to the lungs in the blood. When carbon dioxide levels in the blood increase, the respiratory center in the brainstem increases the rate and depth of breathing to remove excess carbon dioxide. This helps to decrease the amount of acid in the blood and maintain a normal pH. Conversely, when carbon dioxide levels in the blood decrease, the respiratory center decreases the rate and depth of breathing to retain carbon dioxide and increase the amount of acid in the blood. Describe the role of the diaphragm in breathing, including the muscles involved and the changes that occur during inhalation and exhalation. Answer: The diaphragm is a dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. It is the primary muscle involved in breathing. During inhalation, the diaphragm contracts and moves downward, which increases the volume of the thoracic cavity and decreases the pressure in the lungs. This causes air to flow into the lungs. During exhalation, the diaphragm relaxes and moves upward, which decreases the volume of the thoracic cavity and increases the pressure in the lungs. This causes air to flow out of the lungs. Other muscles involved in breathing include the external intercostal muscles, which help to expand the rib cage

Akash Garg M.S.,D.C.

Spartanburg Community College

Companion Guide to Basic Anatomy and Physiology

during inhalation, and the internal intercostal muscles, which help to compress the rib cage during exhalation. Discuss the factors that can affect lung function, including age, smoking, and environmental factors. Answer: Lung function can be affected by a variety of factors, including age, smoking, and environmental factors. As people age, their lung function naturally declines, which can lead to shortness of breath and other respiratory problems. Smoking is a major cause of lung disease, including chronic obstructive pulmonary disease (COPD), emphysema, and lung cancer. Environmental factors, such as air pollution and occupational exposure to dust and chemicals, can also have a negative impact on lung function. Prolonged exposure to these factors can lead to respiratory disorders and may require medical intervention. Describe the process of pulmonary ventilation, including the muscles involved and the changes that occur during inhalation and exhalation. Answer: Pulmonary ventilation is the process of breathing, which involves the movement of air into and out of the lungs. During inhalation, the diaphragm contracts and moves downward, while the external intercostal muscles contract and move the ribs upward and outward. This causes the thoracic cavity to expand and air to flow into the lungs. During exhalation, the diaphragm relaxes and moves upward, while the external intercostal muscles relax and move the ribs downward and inward. This causes the thoracic cavity to contract and air to flow out of the lungs. Other muscles involved in pulmonary ventilation include the internal intercostal muscles, which assist with exhalation, and the accessory respiratory muscles, which can be recruited during times of increased respiratory demand. The process of pulmonary ventilation is controlled by the respiratory center in the medulla oblongata and pons of the brainstem, which responds to changes in carbon dioxide levels, oxygen levels, and blood pH to regulate breathing rate and depth.

Akash Garg M.S.,D.C.

Spartanburg Community College