ELAINE N. MARIEB EIGHTH EDITION 13 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY PART A The Respiratory System

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings I. Respiratory Anatomy Figure ) You can live weeks w/o food, days w/o water, but the cells die within minutes w/o oxygen. 2) Pathway: nose  pharynx  larynx  trachea  bronchi  bronchioles  alveoli

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 3) Nose a) Nostrils (nares): b) Nasal septum: c) Functions: warm, moisten and clean the air d) Ciliated cells move mucous toward the throat, when it is cold they slow and cause a runny nose

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings e) Conchae: f) Palate: g) Paranasal sinus: 4) Pharynx divisions: 1. Nasopharynx: from back of nose to the roof of the mouth 2. Oropharynx: from roof of mouth to the larynx 3. Laryngopharynx: from the larynx to the esophagus

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Upper Respiratory Tract Figure 13.2

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings c) Eustachian (pharyngotympanic) tubes: allow infection to travel to the ear d) Tonsils: 5) Larynx a) Thyroid cartilage: the Adam’s apple b) Epiglottis: c) Cough reflex: expels material that accidentally enters the larynx, doesn’t work when unconscious

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings d) Vocal folds (true vocal cords): Vibrate to create sound 6) Trachea: Reinforced by cartilage 7) Bronchi: 8) Lungs a) Located in the thoracic cavity with the apex up and base above the diaphragm b) Divided into lobes (left-2 right-3) c) Stroma:

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lungs Figure 13.4b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Bronchioles and Alveoli Figure 13.5a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 9) Alveoli: 10) Respiratory membrane: a) Simple diffusion allows gases to move across the membrane b) Total surface area is square meters in a healthy man (40 times more than skin) c) Surfactant: chemical preventing the alveoli from sticking together

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Membrane (Air-Blood Barrier) Figure 13.6

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings II. Physiology: 1) Respiration events: a) Pulmonary ventilation: air moves into and out of the lungs b) External respiration: gas exchange between lungs and blood c) Gas transport: the blood carries the gases d) Internal respiration: gas exchange between the blood and tissues

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 13.10

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 2) Mechanic of breathing a) Breathing depends on volume changes in the chest cavity b) Boyle’s Law: as the volume increases the gas pressure decreases c) Inspiration: diaphragm moves down  volume increase  pressure decreases  air enters d) Expiration: diaphragm moves up  volume decrease  pressure increases  air leaves

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inspiration Figure 13.7a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Expiration Figure 13.7b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 3) The diaphragm does most of the work, but is aided by other muscles during forced inspiration and expiration 4) Volumes and capacities a) Spirometer: instrument used to measure volumes and capacities b) Tidal volume (TV): air normally entering and leaving the lungs (500 ml) c) Inspiratory reserve (IRV): air that can be taken in over tidal volume ( )

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings d) Expiratory reserve (ERV): air that can be forced out above tidal volume (1200) e) Residual volume: air always in the lungs (1200) f) Vital capacity (VC): total amount of exchangeable air (TV + IRV +ERV= 4800 ml) g) Dead space volume: air always in the conducting zones

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Internal Respiration Figure 13.11

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Capacities Figure 13.9

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 5) Respiratory sounds: a) Bronchial sound: air moving through the large passageways b) Vesicular sound: air-filling alveoli 6) Gas transport: a) Hemoglobin: iron molecule in RBC that carry oxygen b) Bicarbonate ion: transport molecule for CO 2 in plasma

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings c) Oxygen is also carried in plasma and a small amount of CO 2 by hemoglobin 7) Respiration control: a) Phrenic and intercosatal nerve: carry impulses regulating breathing b) Medulla and pons: brain center controlling breathing c) Maintains normal breathing between bpm

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings d) Stretch receptors: sense when lungs are full and stop inspiration e) High levels of CO 2 and low pH are important stimuli to increase breathing rate