exam 2 book questions Flashcards
boundaries of the pharyngeal-oral apparatus
the pharyngeal-oral mechanism is a flexible tube that extends from the larnx to the lips
movements capabilities of the oropharynx and laryngopharynx and their roles in changing the regional lumen of the pharynx
3 movements that allow the lumen to be changed in size and shape
- inward and outward movement of their sidewalls
- forward and backward movement of their back wall
- forward backward movement of their front wall (tongue/epiglottis)
know what movements influence the degree of coupling between the pharyngeal cavity and oral cavity
- upward and downward movements of the tongue, upward and downward movements of the velum, side to side movements of the pillars of palatoglossal arch (anterior faucial pillars)
- maximum coupling is made by a combined max elevation of velum and max depression of the tongue
- decoupling results when the undersurface of the velum and upper surface of the tongue are placed in full appostition and the oropharyngeal airway is occluded
know where the tongue derives its mobility
- its rides with the mandible and goes as a whole where the mandible goes
- its position within the oral covity can be shifted en masse as a body
- and its shape can be changed markedly and relatively independently of the first two sources mobility
know how length and cross-sectional changes of the pharyngeal-oral lumen are achieved
length changes:
- within the pharyngeal cavity by different combinations of adjustments of velum and larynx
- within oral cavity, by different combinations of adjustments of tongue and mandible
- within the oral vestibule by different combinations of adjustments of the lips and mandible
cross-sectional changes: (width)
- within the pharynx, by different combinations of adjustments of the tongue, epiglottis, posterior pharyngeal wall and lateral pharyngeal walls
- within oral cavity by different combinations of adjustments of the tongue and mandible
- within the oral vestibule by different combinations of adjustments of the lips, mandible, cheeks, and tongue
walls of the pharynx
- the front wall of the pharynx is partially formed by the back surfaces of the velum, tongue, and epiglottis (otherwise its open at the front and connects with the nasal cavities oral cavity and laryngeal aditus)
- back wall of the oropharynx is the only subdivision that can be seen without special equipment, best vewed when velum is elevated
pharyngeal ends of the auditory tubes
located on the lateral walls of the nasopharyn, when they open they let the pressure equilibrate between the middle ears and atmosphere
characteristions of the pharyngeal, palatine, and lingual tonsils
- pharyngeal tonsil: across the back surface of the nasopharynx, between the pharyngeal orifices of the auditory tubes (large mass of lymphoid tissue), when abnormally enlarded its called adenoid tissue
- palatine tonsils: between anterior and posterior faucial pillars on each side of the isthmus (most referred to colloquially)
- lingual tonsil: back surface of the tongue, broad aggragete of lymph glands distributed across much of the root part of the tongue
visibility of the divisions of the pharynx
- the nasopharynx’s boundary is a reference line extending between the upper surface of the hard palate and the most forward point on the uppermost vertebra
- the oropharynx upper boundary is the lower of the nasopharynx and its lower boundary is the hyoid bone
- the upper boundary of the laryngopharynx is the hyoid bone and lower is the base of the cricoid cartilage where it’s continuous with the esphagus at the front its bound by the back surfarce of the tongue and laryngeal aditus
understand the relationship between the pressure difference across the velopharynx and the compressive pressure needed
- the muscular pressure exerted at any moment must exceed the magnitude of the air pressure difference across the velopharyngeal sphincter (whether it be positive or negative) to prevent the velopharynx from being forced (blown/sucked) open
- so a low compressive force is required to maintian airtight velopharyngeal closer for an activity invoving low oral air pressure and high for activities and high for activitis with high positive oral air pressure
- the greater the air pressure difference acros the velopharynx, the higher the compressive pressure needed to maintain velopharyngeal closure
understand how the pull of gravity affects the muscular force required to move the velum in both the upright and supine body positions
- in upright, the muscle force required to elevate the velum must overcome the pull of gravity, whereas muscle force required to lower the velum is augmented by this pull
- in supine the muscle force to move the velum toward the posterior pharyngeal wall is augmented by the pull of gravity and the msucle force ot move the velum away from the posterior pharyngeal wall must overcome the pull of gravity
understand how nasal patency and nasal airway resistance change depending on body position
- nasal patency (openness) decreases and nasal airwary resistance increases in downright as compared to upright body positions
- this change in patency appears to relate to vascular changes that cause congestion
