Pharynx and larynx Flashcards
pharynx
- this is a funnel shaped tube that lies posterior to and extends inferiorly from the oral and nasal cavities
- it connects the nose, mouth, and throat
- this is divided into three parts
- the external carotid artery supplies the pharynx
nasopharynx
- this is continuous with the nasal cavity and is superior to the soft palate
- lined with pseudostratified ciliated columnar epithelium (respiratory epithelium
- contains openings to the auditory tubes on the lateral walls
- contains the pharyngeal tonsils on the posterior walls
oropharynx
this extends between the soft palate and the base of the tongue at the hyoid bone
- has non-keritinized stratified squamous epithelium (to protect the lining from the friction that will occur when swallowing the bolus)
- contains the palatine tonsils (this is between the two arches
- contains the lingual tonsil (the one on the posterior aspect of the tongue)
laryngopharynx
- this is inferior to the hyoid bone is continuous with the larynx and esophagus
- has non-keritinized stratified squamous epithelium (to protect the lining from the friction that will occur when swallowing the bolus)
what are the palatal muscles
these are the muscles used to elevate the palate
- levator veli palatini
- tensor veli palatini
levator veli palatini
- this is going to elevate the soft palate when swallowing
- innervated by CN X (vagus nerve)
tensor veli palatini
- this is going to tense the soft palate and open the auditory tube when swallowing or yawning
- innervated by CN V (the mandibular division)
- this places a role in balancing pressure in the ear through opening the auditory tubes
what are the laryngeal elevators
- these are the three muscles that act to elevate the pharynx and larynx
- the palatopharyngeus (CN X)
- the salpingopharyngeus (CN X)
- the stylopharyngeus (CN IX)
these contract sequentially to raise the larynx
why do we elevate the larynx
- this is to make sure we do not choke on food or bolus as it comes down to the esophagus
- by bringing the larynx up more proximally, it causes the epiglottis to fold over
- this leads to the closing off the larynx and trachea
pharyngeal constrictors
- we have a superior, middle, and inferior
- these are innervated by CN X (vagus nerve)
- these contract sequentially to push the bolus down the esophagus
describe the larynx and swallowing
- the soft palate is closed off
- the larynx gets elevated and epiglottis closes it off
- sequential contraction of the pharyngeal constrictors
(pushes bolus down to the esophagus)
larynx
- this is connecting the pharynx to the trachea
- this is known as the voice box
- it is a cartilaginous structure that protects and surrounds the glottis and the vocal cords
glottis
a structure in the larynx that consists of the vocal folds and the space in between them
- this is the space and allows for air to leave the pharynx
functions of the larynx
- produce vocalizations
- passageway for air
- prevents ingested material from entering the respiratory tract
- participates in both the sneeze and the cough reflex
- produces sound for speech
what is interesting about the anatomy of the larynx
the larynx is supported by a framework of nine cartilages held in place by ligaments, membranes and muscles
thyroid cartilage
- this is the largest cartilage
- it is not a complete ring and is almost like a c shape
- it acts like a shield
- contains the laryngeal prominence
laryngeal prominence
- this is the adams apple
- everyone has one, it is more prominent on males than females
cricoid cartilage
- this is inferior to the thyroid cartilage
- this is the second largest cartilage
- this articulates with the thyroid cartilage
- has a expanded posterior portion that supports the posterior surface of the larynx
epiglottis
- this is made of elastic cartilage so that it can fold over and close off the larynx
- it is a large cartilaginous flap
- ligaments attach this flap to the hyoid bone
what is the importance of the paired laryngeal cartilages?
- these are smaller cartilages that act as attachment sites for the true and false vocal cords
- arytenoid cartilages
- corniculate cartilages
- cuneiform cartilages
**assist with sound production
vocal folds
folds in the laryngeal wall containing elastic ligaments whose tension can voluntarily be adjusted
- these are the true vocal cords
vestibular fold
- these extend between the thyroid cartilage and the arytenoids
- these are the false vocal cords and do not play a role in the sound production
- the laryngeal epithelium covers these ligaments
- these are relatively inelastic and prevent foreign things from entering the glottis and help protect the vocal cords
what is significant about the location of the larynx in a human compared to other mammals
- our larynx is much lower than other mammals
- this makes us more prone to choking than other animals
- this is why we need all these structures and muscles to help us elevate the larynx when speaking and swallowing
a looser and longer vocal cord means what
this cord will produce a lower pitch
a shorter and tensor cord means what
this will produce a higher pitch
what allows the small cartilaginous structures to affect sound production
- these cartilaginous structures have muscles that attach to them and pull on them to cause the glottis to open and change (increase or decrease) the tension on the vocal cords
what are the extrinsic muscles of the larynx
these are the supra and infrahyoid muscles
what are the intrinsic muscles of the larynx
- these are the muscles moving the laryngeal cartilages
(don’t need to know the names) - these can cause the cartilages to rotate, translate, or glide anteroposterior to the right/left
- these are innervated by the recurrent laryngeal nerves (branch of CN X_
laryngitis
- this is inflammation of the larynx or vocal cords
- causes changes to how people sound (more raspy and hoarse)
- can lead to people losing their voice
recurrent laryngeal nerve
- this is a branch of the vagus nerve that wraps down underneath the aortic arch and supplies the larynx
- damage to this nerve can cause raspiness or hoarseness of the voice
- some surgical procedures could damage this and lead to voice changes
laryngeal cancers
- these are more common in those who smoke
- epithelium below the vocal fold is respiratory tract epithelium
- epithelium above the vocal fold is stratified squamous epithelium
- regions of epithelial transition are prime locations for developing cancer