Respiratory System

• Functions:

  1. ventilation
  2. external respiration
  3. gas transport
  4. internal respiration
  5. regulation of blood pH
  6. production of chemical mediators
  7. voice production
  8. olfaction
  9. protection
• ventilation is also called breathing
• Regulation of blood pH: alteration of blood pH by changing blood CO2 levels..
• The lungs produce ACE enzyme.
• air moving past the vocal folds make sound and speech possible.
• sensation of smell occurs when airborne molecules are drawn into nasal cavity.
• rotection: against some microorganisms by preventing them from entering the body and removing them from respiratory surfaces.
• respiration: the movement of gases across all cell membranes
• primary function of nasal cavity: the air intake portion of the respiratory system; where majority of the warming, cleaning, and humidifying occur
• nasal cavity has conchae and paranasal sinuses
• conchae: 3 bony ridges that act as wind turbines, helping air churn in the nasal cavity
• within the superior and inferior meatuses are openings from paranasal sinuses
• sinusitis: inflammation of the mucous membrane of a sinus
• the pharynx receives air from the nasal cavity and air, food, and drink from oral cavity
• nasopharynx: pharyngeal tonsils within it help defend the body against infection
• oropharynx: begins at the soft palate
• laryngopharynx: Food & drink pass through the laryng. to the esophagus, while air pass through the larynx. However, a small amount of air may be swallowed with food & drink.
• the rigid walls of larynx maintain an open passageway between pharynx and trachea
• larynx's rigidity is due to an outer casing of cartilages connected to one another by muscles and ligaments
• thyroid cartilage: largest cartilage that makes up the larynx
• laryngeal prominence (within the thyroid cartilage): Adam's apple
• cricoid cartilage: ring-shaped
• Arytenoid cartilage, Corniculate cartilage, Cuneiform cartilage: paired cartilages that help move the vocal cords to produce speech
• larynx components:

  1. thyroid cartilage
  2. Adam's apple
  3. cricoid cartilage
  4. epiglottis
  5. Arytenoid, Corniculate, Cuneiform cartilage
• Ligaments of larynx: vestibular folds and vocal folds
• vestibular folds: false vocal cords
• the larynx protects the lower respiratory tract from foreign materials
• laryngitis: person loses his/her voice
• the left lung has a cardiac notch
• trachea AKA windpipe
• the trachea is reinforced with 15 - 20 C-shaped cartilages called tracheal rings
• a mucous membrane lines the trachea which contains goblet cells
• constant long-term irritation to trachea can prevent normal function of the tracheal epithelium
• main bronchi: primary bronchi
• (in bronchi) Carina: important landmark for reading x-rays
• if foreign matter is inspired to the level of carina, it stimulates a powerful cough reflex
• lobar bronchi: secondary bronchi
• the left lung has two lobar, while the right has three
• segmental bronchi: tertiary bronchi
• bronchioles: from continued branching of segmental bronchi