Nose
Nose is divided by the nasal septum into 2 nostrils
Mucosal linings: Warms air coming in and traps foreign objects
Foreign objects disposal: Ciliated cells that propel debris towards the throat
Three ridges: Conchae= increase mucosal surface area and air turbulence to enter the nasal cavity instead of the lungs
Nasal cavity ends with the uvula= prevents food from entering nasal cavity
The nasal cavity is surrounded by parinasal sinuses
Functions of sinuses
lighten the skull
Resonate speech
Produce mucus
Pharynx= throat
Lined with tonsils that trap and remove foreign pathogens
Pharyngeal tonsil, 2 platine & lingual tonsils
Nasopharynx
Oropharynx
Larynphrax
Larynx: connects the pharynx to the trachea
Larynx functions
Provide an open airway: Hyaline cartilage prevents collapse
Divert air and food into the proper pathways: Epiglottis
Produce sound: Vocal cords
How vocal cords change
Volume with variance
Pitch: changing tension
Articulation: using tongue + lips
Trachea= Windpipe
Surrounded by horseshoe shaped cartilage
Rings open toward posterior to allow esophagus to move
Lower Respiratory
Lungs are covered with thin membrane= pleura
Pleural space: contains pleural fluid reducing fluid
Smaller air sacs= alveoli
Alveolus is surrounded by capillaries
Surfactant: Lipid mixture produced by alveoli to prevent collapsing
Thin walled alveoli & surrounding capillaries make up the respiratory zone (site of gas exchange)
A respiratory membrane is found between the capillary and each alveolus
other cells: Alveolar macrophages= collecting bacteria
External respiration: Pulmonary blood vessels to Alveoli
Internal respiration: Blood to body tissues
Muscles involved in breathing: Diaphragm + External intercostals
Muscle contraction: Increasing in volume and decrease in pressure= Inspiration
Muscle relaxation: Decrease in volume and Increase in pressure (expiration)
Structure of breathing
Rate of respiration is controlled within the medulla and pons
Within medulla
VKG= quiet regular breathing
DRG= collects sensory information and passes info to VRG
Within pons
Modifies timing + smooth control of breathing by communicating with VRG
Respiratory rate can change through:
Physical factors
Conscious control (brainstem)
Emotional Factors
Chemical factors
Most important for breathing= amount of co2
Tidal volume: amount exchanged by the lungs at rest
Inspiratory: The additional amount of air that can be inhaled
Expiratory: The additional amount of air that can be exhaled
Residual: The amount of air remaining in the lungs after forced exhalation
Vital capital: amount that can be expired after a maximum inspiration