Respiratory System Biol 105 Lecture 18 Chapter 14

Copyright © 2009 Pearson Education, Inc. Outline - Respiratory System I.Function of the respiratory system II.Parts of the respiratory system III.Mechanics of breathing IV.Regulation of breathing

Copyright © 2009 Pearson Education, Inc. Respiratory system Function  The function of the respiratory system is to bring in oxygen to the body and remove carbon dioxide.

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.1 Breathing moves air in and out of the lungs. External respiration is the exchange of oxygen and carbon dioxide between the lungs and the blood. Internal respiration is the exchange of oxygen and carbon dioxide between blood and the body tissues. Gas transport moves oxygen and carbon dioxide between the lungs and the body tissues. Tissue Gas diffusion Oxygen transport Carbon dioxide transport Lungs

Copyright © 2009 Pearson Education, Inc. This type of tissue covers and lines body parts 1.Connective 2.Epithelial 3.Muscle 4.Nervous

Copyright © 2009 Pearson Education, Inc.  Lined by pseudostratified ciliated columnar epithelial cells. The cilia sweeps mucus, germs and debris toward the throat.  Mucus produced by goblet cells.  Smoking damages the ciliated cells 8-4 Cells lining respiratory tract

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.4a

Copyright © 2009 Pearson Education, Inc. Ciliated cells in respiratory tract

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.3

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.2 (1 of 2) Nasal cavity Produces mucus Filters, warms, and moistens air Olfaction Pharynx Passageway for air and food Sinuses Cavities in skull Lighten head Warm and moisten air Intercostal muscles Diaphragm Muscle sheet between chest and abdominal cavities with a role in breathing UPPER RESPIRATORY SYSTEM RESPIRATORY MUSCLES Cause breathing Filters, warms, and moistens air Move ribs during breathing

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.2 (2 of 2) Epiglottis Covers larynx during swallowing Bronchi Two branches of trachea that conduct air from trachea to each lung Bronchioles Narrow passageways to conduct air from bronchi to alveoli Lungs Structures that contain alveoli and air passageways Allow exchange of oxygen and carbon dioxide between atmosphere and blood Alveoli Microscopic chambers for gas exchange Trachea Connects larynx with bronchi leading to each lung Conducts air to and from bronchi Larynx Air passageway Prevents food and drink from entering lower respiratory system Produces voice LOWER RESPIRATORY SYSTEM Exchanges gases

Copyright © 2009 Pearson Education, Inc.  Functions: 1.filters the air 2.warms the air 3.moisten the air entering the lungs 4.smell (which also plays a role in the sense of taste) Nasal cavity

Copyright © 2009 Pearson Education, Inc.  Parts of the nasal cavity:  Mucus membranes - secrete sticky mucus to trap germs & debris.  Contains olfactory receptor cells for the sense of smell  Sinuses – air filled cavities, warm and moisten air Nasal cavity

Copyright © 2009 Pearson Education, Inc.  Functions - is a passageway for air, liquids, and food. (swallowing begins here). Connects the nasal cavity to the esophagus and the larynx  Tonsils are found here – lymphatic tissue that protects against infection Pharynx

Copyright © 2009 Pearson Education, Inc.  Functions 1. Connects the pharynx to the trachea 2.Cont ains vocal cords used to generate sound 3.Prevents food from entering lower respiratory tract Larynx

Copyright © 2009 Pearson Education, Inc.  Structure made from cartilage  Epiglottis closes the trachea when swallowing Larynx

Copyright © 2009 Pearson Education, Inc.

 Windpipe held open by concentric rings of cartilage  Function – Connects the larynx to the bronchi Trachea

Copyright © 2009 Pearson Education, Inc.  Trachea leads to the bronchial tree: 5. Bronchi (bronchus) 6. Bronchioles 7. Alveoli (alveolus) 8-4 Bronchial Tree

Copyright © 2009 Pearson Education, Inc. The Respiratory System Figure 14.7

Copyright © 2009 Pearson Education, Inc.  Sacs at the end of the bronchioles, they are surrounded by blood capillaries.  Function: It is here that the oxygen diffuses across the membrane into the capillaries, and carbon dioxide goes from the capillaries to the inside of the lungs Alveoli

Copyright © 2009 Pearson Education, Inc. Alveoli  Lungs - have about 300 million alveoli  The structure of the alveoli increases surface area of lung  For alveoli to function properly they are coated with phospholipid molecules called surfactant that keep them open

Copyright © 2009 Pearson Education, Inc. Alveoli Figure 14.8

Copyright © 2009 Pearson Education, Inc. The Respiratory System Table 14.1 (1 of 2)

Copyright © 2009 Pearson Education, Inc. The Respiratory System Table 14.1 (2 of 2)

Copyright © 2009 Pearson Education, Inc. What cells secrete mucus 1.cilliated columnar epi 2.goblet 3.squamous epi 4.osteocytes

Copyright © 2009 Pearson Education, Inc. The tube connecting the larynx to the primary bronchi is 1.pharynx 2.trachea 3.bronchioles 4.alveoli

Copyright © 2009 Pearson Education, Inc. Common passageway for air, food and drink 1.pharynx 2.trachea 3.bronchioles 4.alveoli

Copyright © 2009 Pearson Education, Inc. Conducts air from the trachea to the bronchioles 1.pharynx 2.trachea 3.bronchus 4.alveolus

Copyright © 2009 Pearson Education, Inc. Gas exchange takes place here 1.pharynx 2.trachea 3.bronchioles 4.alveoli

Copyright © 2009 Pearson Education, Inc. Which cavity is the lung located in? 1.abdominal 2.pericardial 3.pleural 4.dorsal

Copyright © 2009 Pearson Education, Inc. Inhalation Figure 14.9a The lungs expand, and air moves in. The chest cavity increases in size, and pressure within the lungs decreases. Diaphragm contracts and flattens Diaphragm contracts Intercostal muscles contract Rib cage moves up and out Air flow Inhalation (a)

Copyright © 2009 Pearson Education, Inc. Inhalation  When the diaphragm and intercostal muscles contract, the volume of the thoracic cavity increases, causing the pressure in the lungs to decrease  Inhalation is also called inspiration

Copyright © 2009 Pearson Education, Inc. Exhalation Figure 14.9b The lungs recoil, and air moves out. The chest cavity decreases in size, and pressure within the lungs increases. Diaphragm relaxes and moves upward Diaphragm relaxes Intercostal muscles relax Rib cage moves down and inward Air flow Exhalation (b)

Copyright © 2009 Pearson Education, Inc. Exhalation  Exhalation = Expiration  When the same muscles relax, volume of the thoracic cavity decreases, pressure in the lungs increase

Copyright © 2009 Pearson Education, Inc. Air Volumes  The volume of air inhaled or exhaled during a normal breath is called the tidal volume  Tidal volume is usually around 500 ml  The volume of air moved into and out of the lungs is an indication of health

Copyright © 2009 Pearson Education, Inc. Air Volumes  Inspiratory reserve volume = forced inhalation volume  Expiratory reserve volume = forced exhalation volume  Residual volume is the amount of air left in the lungs after forced exhalation  Vital capacity is the amount of air brought in and out of the lungs during forced breathing

Copyright © 2009 Pearson Education, Inc. Air Volumes Figure (1 of 2) Inspiratory reserve (forced inhalation) volume Vital capacity Expiratory reserve (forced exhalation) volume Residual volume Tidal volume Total lung capacity Lung Volume (ml)

Copyright © 2009 Pearson Education, Inc.  Remember that O 2 enters and CO 2 leaves the lungs = External respiration  Then O 2 and CO 2 is exchanged between the blood vessels and tissues = Internal Respiration  This gas exchange is due to diffusion 8-14 Gas Exchanges in the Body

Copyright © 2009 Pearson Education, Inc.  Oxygen is transported on Hemoglobin.  When Oxygen is bound to hemoglobin, then it is called Oxyhemoglobin 8-15 Oxygen Transport

Copyright © 2009 Pearson Education, Inc. 1.CO 2 is transported dissolved in the plasma (10%) 2.CO 2 is bound to hemoglobin (20%) 3.CO 2 is converted to bicarbonate ions (70%) 8-14 Carbon Dioxide Transport

Copyright © 2009 Pearson Education, Inc. CO 2 + H 2 O H 2 CO 3 H + + HCO Bicarbonate ions Carbonic anhydrase

Copyright © 2009 Pearson Education, Inc. Diffusion of Gasses: Alveoli and Capillaries Figure (2 of 2)

Copyright © 2009 Pearson Education, Inc. Diffusion of Gasses: Capillaries and Tissues Figure (1 of 2)

Copyright © 2009 Pearson Education, Inc.  Normally we breath ventilations per minute.  This rate is controlled by the medulla oblongata region of the brain. Nerves transmit signal to the diaphragm and muscles.  Chemoreceptors in the medulla oblongata and arteries detect levels of CO 2 and O 2 in the blood, controlling the rate and depth of breathing Regulation of Breathing

Copyright © 2009 Pearson Education, Inc. Important Concepts  Read Ch 15  What is the function of the respiratory system?  What is the location and function of the all the parts of the respiratory system?  What are the parts of the nasal cavity and their functions?  What are the parts of the larynx and their functions?

Copyright © 2009 Pearson Education, Inc. Important Concepts  What cell types lines the trachea, what are their functions, be able to discus how smoking effects this tissue?  Where does the exchange of gases occur in the lungs?  What cavity contains the lungs?  What controls the rate of breathing?  Be able to discuss the mechanics of breathing?

Copyright © 2009 Pearson Education, Inc. Important Concepts  How is oxygen carried in the blood?  How is carbon dioxide carried in the blood, know all the ways, and the which is the predominate mode? (You don’t need to know the chemical equation of bicarbonate formation)  What is the diaphragm and what is its function?

Copyright © 2009 Pearson Education, Inc. Definitions  Goblet cells, sinuses, epiglottis, surfactant, diaphragm, intercostal muscles, Inhalation/inspiration, exhalation/expiration tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume, vital capacity, hemoglobin, oxyhemoglobin, chemoreceptors