Chapter 17 Key Terms 1 AlveoliLarynx TracheaSurfactant RespirationEpiglottis GlottisPleural Cavity InspirationBronchi BronchiolesInternal Respiration Partial PressureVocal folds Thyroid CartilageNasal Septum Eustachian TubeNasopharynx

ANATOMY & PHYSIOLOGY CHAPTER 17: RESPIRATORY SYSTEM 2

Respiratory System  Purpose  Exchange oxygen and carbon dioxide between the atmosphere and the blood  C 6 H 12 O O 2  6 CO H 2 O + 38 ATP  Respiration  The overall exchange of gases between the atmosphere, blood, and cells 3

Respiratory Organs  Nose  Pharynx  Larynx  Trachea  Bronchi  Lungs 4

The Nose  External nares (Nostrils)  Nasal cavity  Divided into left and right nasal cavities by nasal septum  Anterior portion has 3 functions  Warm, moisten, and filter air  Olfactory stimuli are detected  Resonating chambers (sinuses) help create speech sounds 5

The Nose 6  Nasal cavity  Chonchae extend from cavity wall  Nasal cavity divided into passageways  Superior meatus  Middle meatus  Inferior meatus  Chonchae and nasal cavity are lined with mucous membrane  Traps particles filtered by hairs  Cilia moves mucus to back of throat to be swallowed

The Nose 7  Olfactory receptors line the membrane of the superior meatus  Olfactory region  Goblet cells in the membrane secrete mucus  Mucus moistens air and traps particles  Capillaries in the membrane help warm the air

The Sinuses 8  Sinus  Air filled space inside bone  4 Sinuses  Sphenoidal  Frontal  Ethmoidal  Maxillary  Help reduce some of the weight of the head

Pharynx  Also called the throat  Lined with mucous membrane  Nasopharynx – posterior portion of nasal cavity  Connected to the Eustachian tubes  Connect to the middle ear (pressure control)  Oropharynx – passageway for air and food  Laryngopharynx – connection for the mouth and esophagus, and the nose and trachea 9

Larynx  AKA voice box  Thyroid cartilage is most prominent feature (Adam’s apple)  Moves up and down when swallowing/talking  Epiglottis covers the glottis when swallowing  Cough reflex functions when anything other than air enters larynx  False vocal folds – close to keep food from entering lungs  Vocal folds – vibrate to produce speech  Trachea carries air from larynx to the bronchi 10

Bronchi  Trachea divides into right and left primary bronchi  Trachea and bronchi contain incomplete rings of hyaline cartilage  Bronchi branch into bronchioles 11

The Lungs  2 lungs enclosed in pleural membrane  Parietal pleura – attaches lung to wall of thoracic cavity  Visceral pleura – covers the lungs  Pleural cavity – space between those two membranes  Right lung has 3 lobes  Left lung has 2 lobes  Bronchioles contain alveoli  Very thin walls for diffusion (respiratory membrane) 12

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The Respiration Process  Purpose  Supply cells with O 2 and remove CO 2  3 processes  Ventilation/breathing  Exchange of gases between atmosphere and lungs  Inspiration/inhalation and expiration/exhalation  External respiration  Exchange of gases between blood and lungs  Internal respiration  Exchange of gases between blood and cells of the body 14

The Respiration Process  Diaphragm contracts  lungs expand, forcing air into lungs  O2 and CO2 exchanged  diaphragm relaxes, forcing air out  Hemoglobin transports gases in blood  The pressure of a gas determines the rate it diffuses from one area to another  Partial pressure = amount of pressure that gas contributes to the total pressure  Air = 21% O 2  21% x 760 mmHg = mmHg 15

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