Respiratory System A&P Adapted from Dr. Marian Diamond and Essentials of Human Anatomy and Physiology Pearson Education 7th Edition Elaine N. Marieb Function of the Respiratory System  Oversees gas exchanges (oxygen and carbon dioxide) between the blood and external environment  Exchange of gasses takes place within the lungs in the alveoli(only site of gas exchange, other structures passageways  Passageways to the lungs purify, warm, and humidify the incoming air  Shares responsibility with cardiovascular system to distribute blood Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 13.2 Structures of the Respiratory System Science of OtorhinolaryngologyEars, nose, and throat • 3 types of tonsils (full of lymphocytes) 1. Palatine-posterior of oral cavity 2. Lingual-base of tongue 3. Pharyngeal-nasopharynx Which one of these tonsils do we typically remove due to frequent infection? Lingual Tonsils Tonsils with Mono Tonsillectomy CAUTION: Maybe very graphic if you have a weak stomach • https://www.youtube.com/watch?v=Pvj3CAof3k8 • Tonsilloliths aka Tonsil Stones- calcified minerals like calcium, phosphorus, magnesium, ammonia and carbonate found in crevices of the palatine or lingual tonsils • Removal• https://www.youtube.com/watch?v=rO0Cj3iFZBM 2 types of respiration • External respiration occurs when oxygen gas passes from the alveoli of the lungs and enters the blood stream through the capillaries • Internal respiration occurs when the oxygen gas in the blood of a capillary diffuses to the body’s tissues • • • • Structures of the Upper Respiratory System Nose- made of hyaline cartilage Attached to nasal bone External Nares- aka nostrils Functions of the nose: – Cleans air with cilia on pseudostratisfied columnar epithelium – Moistens air with goblet cells that produce mucus – Warms air with venous sinus beneath the epithelium that lines the nasal cavity – Resonates voice – Houses olfactory nerves Types of Pharynx (Throat) • Nasopharynx-nose • Oropharynx-mouth • Laryngopharynx“Food tube” before esophagus Nasopharynx • Eustachian tube originates here to the middle ear to equalize pressure • Home of pharyngeal tonsils • Pseudostratisfied columnar ciliated epithelium with goblet cells Oropharynx • Posterior to oral cavity • Home to palatine tonsils • Stratisfied squamous epithelial tissue Laryngopharynx • Posterior to larynx (windpipe) • Home of lingual tonsils • Stratisfied Squamous epithelial tissue Hard and Soft Palate • Hard palate is the bone of the maxilla – “roof of your mouth” – attached to teeth • Soft palate is the muscle tissue with the uvula - Uvula means “grape” it prevents water/food from getting into your nose from your mouth • Using your tongue you can feel the soft tissue behind the roof of your mouth Cleft Palate • 1 out of 900 children are born with a cleft palate • Exposes mouth to the nasal cavity Sinuses • Hollowed out areas within a bone • Clear air passage ways and help humidify the air as it enters the body • Ethmoid sinus (Ethmoid bone) home of cribiform plate where olfactory nerves send signals to the brain • Sphenoid sinus (Sphenoid bone) Tongue/Tear ducts • Tongue muscle at the base of the mouth attached to the mandible • Nasolacrimal duct is the inner tube that releases tears from the lacrimal glands Larynx • 4-5 inches in length • Anterior of neck • Surrounded by cartilage to keep the lumen (tube) open – Thyroid cartilage: • Largest • Protective shield • Increases in size for males to deepen the voice – Cricoid cartilage: inferior to thyroid complete ring that supports the thyroid and trachea – Voice Box and vocal cords found here http://www.youtube.com/watch?v=E4UG-dkVjrk Larynx: Epiglottis and Glottis • The glottis is the area in between the vocal cords • It is the opening of the larynx • The epiglottis (epi-upon) is what covers the glottis and is controlled by the tongue Top view of larynx http://www.youtube.com/watch?v=zQjJ5Alx40g The Structures of the Lower Respiratory Tract • Trachea (windpipe) – 4-5 inches in length – Connects larynx to bronchi – Rings of cartilage – (ave. 16) supports the structure http://www.youtube.com/watch?v=_Aw7EkIsYK0 Primary Bronchi (Bronchus) • First branches from trachea • Right bronchus is straighter and obstructed more easily • Left bronchus is bent more to make room for the heart Secondary Bronchi • Connected to primary bronchi • Smaller tubes to decrease air volume Tertiary and Terminal Bronchioles • Even smaller tubes made of cartilage to decrease air volume as it travels to the terminal bronchioles • Terminal bronchioles are not made of cartilage – This is where asthma attacks take place due to constriction – Epinephrine is used to dialate the bronchioles Alveoli • Alveoli Duct- is the small tube that extends from the terminal bronchiole to the Alveoli • Alveoli sac- individual hollow open area made of epithelial tissue where gas exchange takes place • Secretes surfactant-liquid that prevents alveoli from sticking to one another • Made also of elastic fibers that expands air when you inhale and recoils when you exhale Lungs • Held in pleural cavity surrounded by parietal and visceral pleura with serous fluid in between the pleura • Right lung has 3 lobes and the Left lung has 2 lobes WHY?? • 2 surfaces: Mediastinal (Mediastinum) and Costal (Intercostal muscles of the ribs) • Diaphragm pushes air out as you exhale • Lung is attached to the body via: – Bronchi – Pulmonary artery and pulmonary vein – Nerves http://www.youtube.com/watch?v=nJuFmyXeHkA Diseases of the Respiratory System • Laryngitis-inflammation of larynx • COPD- Chronic Obstructive Pulmonary Disease – Emphysema-inhales but can’t exhale no elasticity in lungs due to damaged elastic fibers from too much carbon – Bronchitis-long term cough with mucus • Lung Cancer- swollen alveoli, moves rapidly • Tuberculosis (TB)- bacterial infection destroys alveoli by releasing toxins and replaces tissue with scars looses elasticity • Pneumonia- pathogen bacterial infection that causes fluid to build up in the lungs Respiratory Failure Sudden Infant Death syndrome (SIDS)  Apparently healthy infant stops breathing and dies during sleep  Some cases are thought to be a problem of the neural respiratory control center  One third of cases appear to be due to heart rhythm abnormalities Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Neural Control of Breathing • Neural Innervation- controlling rhythm of breathing from pons and medulla of the brain * Phrenic nerve and vagus nerve • Travels through the spinal cord to C3-C4 • Causes the diaphragm to contract • In an emergency if damage occurs above C4 you will need to immediately get oxygen for the individual Respiratory Volumes and Capacities  Normal breathing moves about 500 ml of air with each breath (tidal volume [TV])  Many factors that affect respiratory capacity  A person’s size  Sex  Age  Physical condition  Residual volume of air – after exhalation, about 1200 ml of air remains in the lungs Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Respiratory Volumes and Capacities  Inspiratory reserve volume (IRV)  Amount of air that can be taken in forcibly over the tidal volume  Usually between 2100 and 3200 ml  Expiratory reserve volume (ERV)  Amount of air that can be forcibly exhaled  Approximately 1200 ml Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Respiratory Volumes and Capacities  Residual volume  Air remaining in lung after expiration  About 1200 ml Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Respiratory Volumes and Capacities  Vital capacity  The total amount of exchangeable air  Vital capacity = TV + IRV + ERV  Dead space volume  Air that remains in conducting zone and never reaches alveoli  About 150 ml Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Respiratory Volumes and Capacities  Functional volume  Air that actually reaches the respiratory zone  Usually about 350 ml  Respiratory capacities are measured with a spirometer Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Respiratory Capacities Figure 13.9 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide Air Volume and Lungs Capacity TV