The respiratory system supplies oxygen to the body for aerobic respiration through the inhalation and exhalation or expiration of air. The respiratory tract also protects against dehydration, helps maintain temperature, prevents the entrance of pathogens, and produces sounds. The upper respiratory tract contains the nostrils (nares), vestibule, nasal septum, nasal mucosa, pharynx, larynx, epiglottis, glottis, and cartilage near the hyoid bone. The glottis vibrates the vocal folds to produce sound. The lips, teeth, and tongue manipulate that sound to produce words. The windpipe (trachea), bronchi, and bronchioles draw air deeper into the body so oxygen can be exchanged for carbon dioxide in the alveoli. This lecture also covers the structure of the lungs, breathing, diffusion, the diaphragm, and disorders and conditions of the respiratory tract.
Functions of the respiratory system: providing tissue for gas exchange in/out of the body, physically moving air in/out of body, protecting the body from dehydration/temperature changes/pathogen entrance, and producing sounds (vocalization)
The upper respiratory tract includes the external nares, vestibule, nasal septum, nasal conchae, nasal mucosa, and pharynx
The lower respiratory tract includes the larynx (epiglottis, glottis, hyoid, cartilages, ligaments, vocal cords), trachea, bronchi, bronchioles, and alveoli of the lungs
Sound production involves air being pushed across the vocal folds and is a combination of phonation plus articulation
The trachea, bronchi, and bronchioles have a mucosa lining with cilia that are meant for sweeping up mucus generated in the lower parts of the respiratory tree
Bronchoconstriction is when the passageways (lumen) in the bronchioles get thinner and bronchodilation is when the passageways in the bronchioles get wider
Alveoli (one-cell thick) are microscopic air sacs in the lungs that are responsible for getting oxygen into the blood stream and carbon dioxide out of the bloodstream, through passive transport
Without surfactant, alveolar sacs would not be able to stay open and functioning due to surface tension problems
The left lung has 2 lobes and the right lung has 3 lobes, separated by deep fissures and wrapped up in pleural membranes
The parietal pleura is a protective wrapping on the surface of the lungs, the visceral pleura is the wrapping on the inside of the thoracic cage, and in between the two layers there is fluid for lubrication/protection
The diaphragm and intercostal muscles are the main muscles that allow breathing to occur
Respiratory volumes can be chartered to study variations or abnormalities in the breathing of a human
Partial pressures of gases (oxygen, carbon dioxide, nitrogen, etc) determine where they move
Respiratory conditions/disorders include asthma, emphysema, tuberculosis (TB), and pneumonia
Did you know…
Q: How long can the average person hold their breath?
A: Under one minute. Most people let psychological distress prevent them from holding their breath longer (whether they’re in water or not). The more a person can increase their inspiratory volume before holding their breath, the longer they can go. On the reverse end of the spectrum there is an indigenous tribe on an island in the Pacific Ocean that has been catching crustaceans, etc. under water for so many generations that they have been reported to be able to hold their breath for 8-10 minutes!
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
This book is the ninth edition of the top-selling Human Anatomy & Physiology text and the authors have produced the most accessible, comprehensive, up-to-date and visually stunning anatomy & physiology textbook on the market.. It presents information in smaller and more digestible bites, making it easier to read and navigate.
This book has a superb balance between structure and function and continue to emphasize the correlations between normal physiology and pathophysiology, normal anatomy and pathology, and homeostasis and homeostatic imbalances. The acclaimed illustration program continues to be refined and is unsurpassed in the market. The thirteenth edition is fully integrated with a host of innovative electronic media, including WileyPlus 5.0 (access purchased separately.) No other text and package offers a teaching and learning environment as rich and complete.
This book includes updated examples, references, and dozens of illustrations. Readers of the new edition will come to understand the meanings of terms in anatomy and physiology, get to know the body's anatomical structures, and gain insight into how the structures and systems function in sickness and health. It also features updated information on how systems function in illness and in health.