Chapter 22 Respiratory System Lecture 7 Marieb’s Human Anatomy and Physiology Marieb w Hoehn Chapter 22 Respiratory System Lecture 7 Slides 1-15; 80 min (with review of syllabus and Web sites) [Lecture 1] Slides 16 – 38; 50 min [Lecture 2] 118 min (38 slides plus review of course Web sites and syllabus)

Lecture Overview Overview of respiration Functions of breathing Organs of the respiratory system Nose, nasal cavity, sinuses Pharynx Larynx Trachea Bronchial tree Lungs

Respiratory System Respiration (in the respiratory system) is the process of exchanging gases between the atmosphere and body cells. It consists of the following events (in the order you should know): *pulmonary ventilation *external respiration transport internal respiration cellular respiration Functions of the respiratory system We breathe: 1. To provide O2 for cellular respiration and 2. To rid our bodies of CO2 (waste gas)

Other Functions of the Respiratory System Speech and vocalization Provides scaffold for sense of smell Control of pH Helps produce angiotensin II Movement of blood and lymph Useful in urination, defecation, and childbirth

Organs of the Respiratory System Upper respiratory tract – nose, nasal cavity, sinuses, and pharynx (larynx – some texts) Lower respiratory tract – larynx, trachea, bronchial tree, lungs Conducting portion carries air; nose to the terminal bronchioles Respiratory portion exchanges gases; respiratory bronchioles and alveoli Figure from: Hole’s Human A&P, 12th edition, 2010 ‘ynx’ pronounced like ‘inks’

Location of Lungs Apex Base Figure from: Hole’s Human A&P, 12th edition, 2010 Apex Base

Upper Respiratory Tract Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001 Nasal cavity and turbinates warm and humidify the air before it goes into the lower respiratory passages. What types of epithelium would you expect to find? Why?

Anatomy of the Nasal Region Figures from: Saladin, Anatomy & Physiology, McGraw Hill, 2007 The nose: 1) warms, 2) cleans, and 3) humidifies air

Please don’t do this!

Paranasal Sinuses Mucus membrane-lined, air-filled spaces in maxillary, frontal, ethmoid, and sphenoid bones that drain into the nasal cavity Sinuses: Reduce skull weight Serve as resonating chambers Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Mucous in Respiratory Tract Respiratory mucosa lines the conducting passageways and is responsible for filtering, warming, and humidifying air. Cilia move mucus and trapped particles from the nasal cavity (>10 µm) to the pharynx, and lower respiratory tract (1-5 µm) to pharynx Upper respiratory removal is essentially 100% for particles 10 um and larger and approximately 80% at 5 um. It drops progressively with further reduction in size and approaches zero at 1 to 2 um. The Mucus Escalator Irritation of any sort greatly increases mucus production

Larynx (Voice Box) Larynx C4-C5 (Laryngeal prominence; Adam’s Apple) Figure from: Hole’s Human A&P, 12th edition, 2010 C4-C5 (Laryngeal prominence; Adam’s Apple) Larynx C6 Hyaline cartilage anterior Elastic cartilage Larynx: 1) provides patent airway 2) switching mech for food and air 3) voice production (vocal cords) posterior

Larynx Vestibular folds Protective Sound Covered by folds of laryngeal epithelium that project into glottis Vocal folds (cords) Vestibular folds Inelastic Elastic Posterior Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Larynx Coronal section, posterior view Figure from: Hole’s Human A&P, 12th edition, 2010 Glottis = vocal folds + the opening between them Coronal section, posterior view

Vocal Folds (Cords) Figure from: Hole’s Human A&P, 12th edition, 2010 Sound originates in vocal folds (cords) but is modified to create recognizable speech by: Pharynx - Mouth - Nasal cavity - Sinuses Posterior Closed Open Posterior Pitch of sound: diameter, length, and tension of vocal folds. Diameter and length are fixed; tension is controlled by voluntary muscles.

Movement of the Vocal Folds Speech Inhalation Figures from: Saladin, Anatomy & Physiology, McGraw Hill, 2007

Trachea & Primary Bronchi Posterior Note that the trachea is anterior to the esophagus (T5) (T6) Anterior C-rings of cartilage: 16-20 incomplete rings completed posteriorly by trachealis muscle keep trachea open (patent) Figures from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Try not to inhale seeds!! The growing tree!! http://www.dailymail.co.uk/news/article-1169861/Shocked-Russian-surgeons-open-man-thought-tumour--FIR-TREE-inside-lung.html

Tracheotomy / Tracheostomy Performed to allow air to bypass an obstruction within the larynx Figure from: Hole’s Human A&P, 12th edition, 2010

The Lungs 3 lobes 2 lobes Note that the number of secondary bronchi = number of lung lobes Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Transverse Section of Lungs Figure from: Hole’s Human A&P, 12th edition, 2010 Note that the pleural space is a ‘potential’ space and under a vacuum

The Bronchial Tree From 1 to > 65,000 branches!! How many levels of branching would that be?  Figure from: Saladin, Anatomy & Physiology, McGraw Hill, 2007

Bronchial Tree Figure from: Hole’s Human A&P, 12th edition, 2010

Bronchial Tree Bronchi Bronchioles Alveolar structures Trachea (No cartilage, few/no smooth muscle) (Cartilage + smooth muscle) (Smooth muscle) Bronchi Bronchioles Alveolar structures Primary Secondary (lobar) Tertiary (segmental) Alveolar ducts Alveolar sacs Alveoli Intralobular Terminal Respiratory Trachea Which parts here constitute the conducting portion of the respiratory tree? Know this chart

Bronchial Tree Carina Bronchi - Primary; w/ blood vessels - Secondary (lobar); two on left, three on right - Tertiary (segmental); supplies a broncho- pulmonary segment; 10 on right, 8 on left Bronchioles - Intralobular; supply lobules, the basic unit of lung - Terminal; 50-80 per lobule - Respiratory; a few air sacs budding from theses Bronchioles are to the respiratory system what arterioles are to the circulatory system Intralobular Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Lobules of the Lung The Lobule is the basic unit of structure and function in the lung (Intralobular) Terminal and respiratory bronchioles are lined with cuboidal epithelium, few cilia, and no goblet cells Figure from: Martini, Anatomy & Physiology, Prentice Hall, 2001

Alveoli Figure from: Hole’s Human A&P, 12th edition, 2010

Alveoli Septal (Type II) cells produce surfactant to keep the walls of the alveoli from collapsing

Review Respiration We breathe Organs of the respiratory tract The entire process of gas exchange between the atmosphere and the body Made up of five events We breathe To take in O2 To eliminate CO2 Organs of the respiratory tract Upper; nose, nasal cavity, sinuses, pharynx Lower; larynx, trachea, bronchial tree, lungs

Review Functions of the nose/nasal cavity Sinuses Pharynx Warm and humidify air Trap particulate matter Sinuses Mucous-lined, air filled cavities; communicate with nasal cavity Lighten skull and provide resonating chamber Pharynx Back of mouth (throat) Passage of food/air; aids in speech

Review Respiration We breathe Organs of the respiratory tract The entire process of gas exchange between the atmosphere and the body Made up of five events We breathe To take in O2 To eliminate CO2 Organs of the respiratory tract Upper; nose, nasal cavity, sinuses, pharynx Lower; larynx, trachea, bronchial tree, lungs

Review Functions of the nose/nasal cavity Sinuses Pharynx Warm and humidify air Trap particulate matter Sinuses Mucous-lined, air filled cavities; communicate with nasal cavity Lighten skull and provide resonating chamber Pharynx Back of mouth (throat) Passage of food/air; aids in speech

Review Larynx (voice box) Trachea Bronchial Tree Cartilaginous structure Passageway for air entering trachea Keeps foreign objects out of trachea Contains vocal cords (folds) for speech (to what ligament does the arytenoid cartilage attach) Trachea Air passage with cartilaginous rings; trachealis Cartilage prevents collapse Bronchial Tree Bronchi (Primary, Secondary, Tertiary) Bronchioles (Intralobular, terminal, respiratory) Alveolar structures (ducts, sacs, alveoli)

Review Bronchi Bronchioles Alveolar structures Cartilage and smooth muscle Primary; divisions of trachea; extrapulmonary Secondary; lobar – 2 on left, 3 on right Tertiary; segmental Bronchioles Smooth muscle mainly Intralobular; supply structural unit of lung (lobule) Terminal; 50-80 per secondary lobule Respiratory; have air sac budding off Alveolar structures Neither smooth muscle nor cartilage Ducts, sacs, alveoli Highly vascular; site of gas exchange (O2, CO2)

Bronchial Tree Bronchi Bronchioles Alveolar structures Trachea (No cartilage, few/no smooth muscle) (Cartilage + smooth muscle) (Smooth muscle) Bronchi Bronchioles Alveolar structures Primary Secondary (lobar) Tertiary (segmental) Alveolar ducts Alveolar sacs Alveoli Intralobular Terminal Respiratory Trachea Which are conducting, which are respiratory?

Review Lungs Right and left separated by heart and mediastinum Surrounded by pleura separated by pleural cavity Hilum is area where respiratory tubes and blood vessels pass Left lung has two lobes (with cardiac notch) Right lung has three lobes Lobules Formed by connective tissue division of lobes Basic structural and functional units of lung Contain terminal bronchioles, alveolar structures, nerves, blood vessels, and lymphatics