Ch.22- The Respiratory System

• What transport is gas exchange?

  passive transport

  
• How does gas exchange occur?

  diffusion

  
• Where does gas exchange occur?

  alveoli

  
• What is the cause of emphysema?

  chemical pollutants, smoke
• What is responsible for speech?

  larynx
• What controls the breathing process?

  medulla oblongata

  
• What is the respiratory system?

  Provides oxygen to the body, disposes of CO2, and helps regulate blood pH
• How does the respiratory system work?

  Gas exchange occurs in air sacs of the lungs, called alveoli and at capillary beds around the body.
• Why is the respiratory system important?

  Without oxygen, cells will eventually die. Too much CO2 in the blood will cause the blood pH to become acidic, which will interfere with the cellular function.
• Organs of the respiratory system


  1. Nose

  2. Pharynx

  3. Larynx

  4. Trachea

  5. Bronchi

  6. Lungs-alveoli
• Gas exchanges between blood and external environment occurs only in the

  alveoli of the lungs
• Upper respiratory tract includes:

  passageways from the nose to larynx
• Lower respiratory tract includes:


  - passageways from trachea to alveoli

  - passageways to the lungs purify, humidify, and warm incoming air
• Nose


  the only externally visible part of the respiratory system
• Nostrils(nares)


  the route through which air enters the nose
• Is the nasal cavity, superior or inferior to the nasal cavity?

  Inferior; 0lfactory epithelium
• Nasal septum divides where?

  the nasal cavity
• respiratory mucosa function


  -lines the nasal cavity

  -Moistens air

  - Traps incoming foreign particles

  - Destroys bacteria chemically through the action of lysozyme enzymes

  - Moves contaminated mucus to the posterior of the throat
• Conchae are projections from the lateral walls which increase:


  - Surface area

  - Air turbulence within the nasal cavity

  - Trapping of inhaled particles
• Two palates separate the nasal cavity from the oral cavity

  Hard and Soft
• hard palate


  anterior portion, supported by bone
• soft palate


  posterior portion, not supported by bone
• Parasinal sinuses


  Cavities within the frontal, sphenoid, ethmoid, and maxillary bones surrounding the nasal cavity
• Sinuses


  -Lighten the skull

  - Act as resonance chambers for speech

  - Produce mucus
• the pharynx is commonly called the


  throat
• Muscular passageways from nasal cavity to larynx


  Continuous with the posterior nasal regions
• Three regions of the pharynx

  1. Nasopharynx

  2. Oropharynx

  3. Laryngopharynx

  
• Nasopharynx


  superior region behind nasal cavity
• Oropharynx


  middle region behind mouth
• Laryngopharynx


  inferior region attached to larynx
• Oropharynx and Laryngopharynx serve as common passageway for air and food


  Epiglottis routes food into the posterior tube, the esophagus
• pharyngotympanic tube open into the nasopharynx


  drains the middle ear
• Tonsils are clusters of lymphatic tissue that play a role in protecting


  the body from infections
• pharyngeal tonsils (adenoids)


  located in the nasopharynx

  
• Palatine tonsils(2)


  located in the oropharynx at the end of the soft palate

  
• Lingual tonsil


  base of tongue

  
• Tubal tonsil


  protect the openings of the pharyngotympanic tubes

  
• Larynx is also known as

  voice box
• Larynx functions


  - Routes air and food into the proper channels

  - Plays a role in speech
• The larynx is located

  inferior to the pharynx