9 The Respiratory System Lesson 9.1: Functions and Anatomy of the Respiratory System Lesson 9.2: Respiration: Mechanics and Control Lesson 9.3: Respiratory Disorders and Diseases

Functions and Anatomy of the Respiratory System Chapter 9: The Respiratory System Lesson 9.1 Functions and Anatomy of the Respiratory System

Function of the Respiratory System Gas exchange provides a constant supply of oxygen eliminates carbon dioxide Cardiopulmonary system respiratory system and cardiovascular system work collaboratively to conduct gas exchange

Function of the Upper Respiratory System Filter and remove foreign particles from inhaled air Humidify and control the temp. of the inhaled air Produce sound (voice) Provide and sense of smell (olfactory sense) Aid in immune defense Conduct air to the lower respiratory tract

Anatomy of the Respiratory System

Anatomy of the Respiratory System the nose nares – 2 openings where air enters

Nasal Cavity nasal septum vestibular region olfactory region divides the nasal cavity into left and right chambers vestibular region front of the nasal cavity contain nasal hairs which trap and prevent particles from entering the nose olfactory region contains olfactory receptors – provide sense of smell respiratory cavity lined with a mucosal membrane warms the air that we breathe

Nasal Cavity conchae 3 uneven scroll-like nasal bones superior, middle, and inferior conchae create 3 passageways so more particles can be trapped in the mucous membranes

Nasal Cavity palate uvula anterior portion supported by bone separates the nasal cavity from the mouth hard palate anterior portion supported by bone soft palate posterior portion composed of soft muscle and tissue cleft palate parts of the palate do not completely fuse together during fetal development uvula small mass of connective tissue hanging from the soft palate prevents food from entering the nasal cavity

Cleft Palate

Sinuses air-filled cavities that surround the nose lined with mucous membranes 4 sinuses – frontal, ethmoidal, sphenoidal, maxillary sinus infection – causes the sinuses to become swollen and filled with fluid and germs

Sinusitis

Pharynx muscular passageway that transports air, food, and liquids from the nasal and oral cavities to the trachea and esophagus part of both the digestive and respiratory system composed of nasopharynx, oropharynx, and laryngopharynx nasopharynx transports air oropharynx and laryngopharynx transport air, food, and liquid

Pharynx tonsils pharyngeal tonsil – located in the upper part of the nasopharynx palatine and lingual tonsils – located in the upper portion of oropharynx bacteria and other pathogens become trapped in the tonsils – line of defense

Larynx voice box located inferior to the pharynx transports air and food to the proper passageways composed of 8 cartilaginous plates largest cartilaginous plate, thyroid cartilage, is the Adam’s apple epiglottis flap of cartilaginous tissue as food or liquid is swallowed, the epiglottis covers the pharynx preventing the food and liquid from entering the trachea vocal cords – a pair of folds that vibrate to produce sound glottis – space between the vocal cords

Larynx

Trachea windpipe extends from the end of the larynx to the 5th thoracic vertebra walls are lined with a mucous membrane containing ciliated epithelium c-shaped rings anterior side contains rigid cartilage that provides support posterior side doesn’t contain cartilage and provides flexibility

The Upper Respiratory Tract

Bronchi primary bronchi secondary and tertiary bronchi bronchioles extends from the bottom of the trachea to the left and right lungs wider and shorter bronchus on the right also hangs more vertically secondary and tertiary bronchi branch out from the primary bronchi bronchioles branch out from the tertiary bronchi

Alveoli grape-like clusters at the ends of bronchioles air-filled sacs main site of gas exchange in the lungs walls are composed of thin squamous epithelial cells surfactant – phospholipid that coats the walls reduces surface tension in the alveoli and prevents them from collapsing macrophages – bacteria ingesting cells inside alveoli pores of Kohn – small opening in the alveolar wall that allow gases and macrophages to pass Lungs

Alveolar Capillary Membrane made up of alveoli and surrounding capillaries allows oxygen to diffuse from the alveoli to the capillaries allows carbon dioxide to be transported from the blood into the alveolar sac gas exchange occurs rapidly because: large surface area of lungs alveolar capillary membrane is very thin gas exchange occurs by diffusion

Lungs mediastinum apex base central area of the thoracic cavity between the lungs apex upper part of lung base lower part of lung that rests on the diaphragm right lung has 3 lobes – superior, middle, and inferior lobes left lung has 2 lobes – superior and inferior lobes

Lungs pleural sac composed of 2 slippery serous membranes parietal pleura – lines the thoracic wall and diaphragm visceral pleura – covers lungs

Review and Assessment Match these words with 1–4 below: surfactant, apex, epiglottis, conchae. 1. lungs 2. larynx 3. nasal cavity 4. alveoli

Respiration: Mechanics and Control Chapter 9: The Respiratory System Lesson 9.2 Respiration: Mechanics and Control

Respiration also known as breathing air always moves from a higher pressure area to a lower pressure area

Respiration four key tasks involved in respiration pulmonary ventilation air is moved continuously into and out of the lungs external respiration oxygen from outside the body fills the lungs and alveoli allows gas exchange between the alveoli and pulmonary blood respiratory gas transport oxygen and carbon dioxide are transported in the blood to and from different body tissues internal respiration gas exchange occurs between the tissues and capillaries

Respiration Boyle’s law as the volume of a gas increases, the pressure of the gas decreases at rest, both atmospheric (outside of body) and intrapulmonary (inside lung) are 760 mmHg for air to be pulled into the lungs, intrapulmonary pressure must be less than the atmospheric pressure when air is expelled from the lungs, intrapulmonary pressure must be greater than the atmospheric pressure Boyle's Law

Respiration inspiration (inhalation) expiration (exhalation) diaphragm contracts and flattens intercostal muscles contract thoracic cavity expands creating a vacuum and pulling air into the lungs pressure inside the lungs is less than the atmospheric pressure expiration (exhalation) diaphragm and intercostal muscles relax thoracic cavity shrinks pushing air out of the lungs pressure inside the lungs is greater than the atmospheric pressure

Respiration

Nonrespiratory Air Maneuvers

Control of Breathing average respiration rate for adults at rest = 12-15 breaths per minute Factors affecting the respiration rate: gender – females have smaller lung capacities and therefore, greater respiratory rates infants have greater smaller lung capacities and greater respiratory rates (40-60 breaths per minute) postural position – standing almost doubles respiratory rate compared to a reclined position exercise

Control of Breathing neural factors medulla oblongata pons sets the normal breathing pace pons fine-tunes respiratory rate and depth as the lungs fill with air, stretch receptors in the bronchioles and the alveoli trigger the Hering-Breuer reflex to prevent over inflation of the alveolar sacs coordinates transition between inspiration and expiration

Control of Breathing chemical factors central chemoreceptors located in the respiratory centers in the brain respond to a decrease in cerebrospinal fluid pH – indicates a high amount of CO2 in the body increases the rate and depth to increase O2 and decrease CO2 peripheral chemoreceptors located in the aorta and carotid arteries stimulate respirations in response to changes in oxygen blood levels mechanoreceptors located in muscles and joints detect muscle contraction and force generation during exercise – increase ventilation

Control of Breathing

Lung Volume static measures air volume in lungs measured by using a spirometer may detect lung disorder or deficiency

Lung Volume dynamic measures air volume in lungs based on time measured using a flow volume meter often assesses the ability of the lungs to forcibly expire air in one second can detect asthma or obstructive lung disease

Review and Assessment True or False? 1. The pons and medulla control breathing. 2. Static lung volume involves time. 3. Muscles contract in inspiration. 4. Larger gas volume, higher pressure. 5. Gas moves from low to high pressure.

Respiratory Disorders and Diseases Chapter 9: The Respiratory System Lesson 9.3 Respiratory Disorders and Diseases

Upper Respiratory Tract Illnesses

Upper Respiratory Tract Illnesses avoiding URIs cover when sneezing and coughing wash hands don’t touch hands to eyes, nose, mouth Influenza viral infection vaccine icyimage/Shutterstock.com

Lower Respiratory Tract Illnesses acute bronchitis inflammation of the mucous membranes that line the trachea and bronchial passageways results from an ongoing viral infection such as influenza or the common cold pneumonia usually a viral or bacterial infection of the lungs immune response to the virus or bacterium damages and sometimes kills the cells of the lungs fluid builds up in the lungs, making gas exchange difficult

Lower Respiratory Tract Illnesses tuberculosis highly contagious infection most commonly attacks the lungs but can spread to other organs

Chronic Obstructive Pulmonary Diseases causes smoking characterized by long term airway obstruction living with COPD STOP SMOKING!!! purse-lipped breathing helps maximize breathing and ease shortness of breath patients inhale through their nose and slowly release the air through pursed or puckered lips no cure

Chronic Obstructive Pulmonary Diseases emphysema chronic inflammation of the lungs that damages the alveolar ducts and sacs damage to capillary bed decreased lung surface area poor gas exchange leads to hyperventilation pink puffers exertion from breathing causes patients to develop a pink appearance to the face

Chronic Obstructive Pulmonary Diseases chronic bronchitis inflammation of the bronchi and mucous production obstruct airways risk of bacterial infection mucous production causes a decrease in respiratory rate with an increase in cardiac output blue bloaters face and lips turn blue due to hypoxia (lowered arterial blood oxygen content) bloated appearance

Asthma asthma attack inflamed and narrowed airways cause bronchospasms caused by allergens or irritants treatment relaxes muscles to expand airways xavier gallego morel/Shutterstock.com

Lung Cancer more deaths from lung cancer than other cancers non-small cell lung cancer more common lung cancer common in smokers spreads slowly small cell lung cancer less common lung cancer spreads quickly

Review and Assessment Fill in the blanks with: small cell, bronchospasms, decreased lung surface area, or infection. 1. An asthma attack includes _______________. 2. A symptom of emphysema is _______________. 3. The more common lung cancer is _______________. 4. Tuberculosis is caused by _______________.