Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory System Take a big whiff!

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Why do we need to breathe? All cells need oxygen Cellular Respiration: Process of breaking down glucose into ATP

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Organs of the Respiratory system Nose Nose Pharynx Pharynx Larynx Larynx Trachea Trachea Bronchi Bronchi Lungs – alveoli Lungs – alveoli Figure 13.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Function of the Respiratory System Oversee gas exchanges between the blood and external environment (air) Oversee gas exchanges between the blood and external environment (air) Exchange of gases takes place within the lungs in the alveoli Exchange of gases takes place within the lungs in the alveoli Passageways to the lungs purify, warm, and humidify the incoming air Passageways to the lungs purify, warm, and humidify the incoming air

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

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Pharynx & Tonsils

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Larynx (Voice Box) Routes air and food into proper channels Routes air and food into proper channels Plays a role in speech Plays a role in speech Made of eight rigid hyaline cartilages and a flap of elastic cartilage (epiglottis) Made of eight rigid hyaline cartilages and a flap of elastic cartilage (epiglottis)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Trachea (Windpipe)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsLungs

Respiratory Tree Divisions

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Tree Divisions 1 o (primary) bronchi 1 o (primary) bronchi 2 o (secondary) bronchi 2 o (secondary) bronchi 3 o (tertiary) bronchi 3 o (tertiary) bronchi Bronchioles Bronchioles Terminal bronchioles Terminal bronchioles Alveoli Alveoli

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsBronchioles

Respiratory Membrane (Air-Blood Barrier) Simple squamous epithelium lines alveolar walls Simple squamous epithelium lines alveolar walls Pulmonary capillaries cover ext. surfaces of alveoli Pulmonary capillaries cover ext. surfaces of alveoli

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

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 Gas Exchange Gas crosses the respiratory membrane by diffusion Gas crosses the respiratory membrane by diffusion O 2 enters the blood (from alveoli) O 2 enters the blood (from alveoli) CO 2 enters the alveoli (from blood) CO 2 enters the alveoli (from blood) Macrophages add protection Macrophages add protection

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Mechanics of Breathing (Pulmonary Ventilation) Completely mechanical process Completely mechanical process Depends on volume changes in the thoracic cavity Depends on volume changes in the thoracic cavity Volume changes lead to pressure changes, which lead to the flow of gases to equalize pressure Volume changes lead to pressure changes, which lead to the flow of gases to equalize pressure

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Mechanics of Breathing (Pulmonary Ventilation) Two phases Two phases Inspiration (inhalation)– flow of air into lung Inspiration (inhalation)– flow of air into lung Expiration (exhalation) – air leaving lung Expiration (exhalation) – air leaving lung

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inspiration (a.k.a. Inhalation) Diaphragm and intercostal muscles contract Diaphragm and intercostal muscles contract The size of the thoracic cavity increases (decreasing pressure) The size of the thoracic cavity increases (decreasing pressure) External air is pulled into the lungs due to an increase in intrapulmonary volume External air is pulled into the lungs due to an increase in intrapulmonary volume

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Expiration (a.k.a exhalation) Largely a passive process Largely a passive process Depends on natural lung elasticity Depends on natural lung elasticity As muscles relax, air is pushed out of the lungs As muscles relax, air is pushed out of the lungs Forced expiration can occur mostly by contracting internal intercostal muscles to depress the rib cage Forced expiration can occur mostly by contracting internal intercostal muscles to depress the rib cage

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

Oxygen Transport in the Blood Inside red blood cells attached to hemoglobin (oxy-hemoglobin) Inside red blood cells attached to hemoglobin (oxy-hemoglobin) A small amount is carried dissolved in the plasma A small amount is carried dissolved in the plasma

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Carbon Dioxide Transport in the Blood Mostly transported in the plasma Mostly transported in the plasma A small amt is carried inside red blood cells on hemoglobin A small amt is carried inside red blood cells on hemoglobin

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Gas Exchange Figure 13.11

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cilia Cilia – tiny hairs that beat debris up & out of lungs.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Mucus a.k.a Phelm Mucus – warms, moistens, & filters the air. - To be swallowed or spit out. Avg Person – 1 liter of phelm a day!

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Factors Influencing Respiratory Rate and Depth Physical factors Physical factors Increased body temperature Increased body temperature Exercise, Talking, Coughing Exercise, Talking, Coughing Volition (conscious control) Volition (conscious control) Emotional factors Emotional factors Carbon dioxide levels Carbon dioxide levels Oxygen levels Oxygen levels

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Disorders: Chronic Obstructive Pulmonary Disease (COPD) Chronic bronchitis Chronic bronchitis Emphysema Emphysema Major causes of death and disability in US Major causes of death and disability in US

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Disorders: Chronic Obstructive Pulmonary Disease (COPD) COPD patients: COPD patients: history of smoking (usually) history of smoking (usually) labored breathing (dyspnea) Worsens over time labored breathing (dyspnea) Worsens over time coughing and frequent lung infections coughing and frequent lung infections Often develop respiratory failure Often develop respiratory failure

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lung Cancer 1/3 of all cancer deaths in US 1/3 of all cancer deaths in US associated w/ smoking associated w/ smoking

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsEmphysema

Asthma Chronic inflamed hypersensitive bronchioles Chronic inflamed hypersensitive bronchioles Response to irritants – constriction, coughing, and wheezing Response to irritants – constriction, coughing, and wheezing

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Birth Defects Cystic fibrosis – oversecretion of thick mucus clogs the respiratory system Cystic fibrosis – oversecretion of thick mucus clogs the respiratory system Cleft palate Cleft palate

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin CummingsAging Elasticity of lungs decreases Elasticity of lungs decreases Vital capacity decreases Vital capacity decreases Blood oxygen levels decrease Blood oxygen levels decrease Stimulating effects of carbon dioxide decreases Stimulating effects of carbon dioxide decreases More risks of respiratory tract infection More risks of respiratory tract infection

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lung Model Cut bottom off small water bottle Cut bottom off small water bottle Tie fingers from 1 glove Tie fingers from 1 glove Cover bottom of bottle with cuff of glove Cover bottom of bottle with cuff of glove Tape to seal Tape to seal Insert deflated balloon Insert deflated balloon Wrap mouth-piece of balloon over top of bottle Wrap mouth-piece of balloon over top of bottle