Pharynx and Larynx Flashcards
What are the three functions of the larynx?
Protection/isolation of the airway from the digestive tract
Control pulmonary air pressure
Vocalization
What are the four cartilages of the larynx?
Epiglottis - Arytenoid - Thyroid - Cricoid
What is the paired set of cartilages in the larynx?
Arytenoid
What does the stalk of the epiglottis do?
Articulates with the thyroid cartilage on ventral midline
What does the caudal horn of the thyroid cartilage articulate with?
Cricoid cartilage
What are the two membranes of the larynx?
Vestibular and Vocal
Where are the vocal ligaments located?
Cranial edge of a membrane that connects the cricoid, thyroid, and vocal processes of the arytenoid
What is the action of the cricothyroideus m.?
Thyroid cartilage rotates at the cricothyroid joint
What are the four effects of the laryngeal muscles on the vocal folds?
Adduction - Abduction
Lengthening - Shortening
What does adduction of the vocal folds cause?
restricts airflow or produce phonation
What does abduction of the vocal folds cause?
Increase airflow
What does lengthening of the vocal folds cause?
Raise pitch of sound produced
What does shortening of the vocal folds cause?
Lower the pitch of the sound
What is the only muscle that abducts the vocal folds?
Dorsal Crucoarytenoid
What are the five major nerves to the Larynx?
Cranial - External - Internal - Recurrent - Caudal
What does the cranial laryngeal nerve come off of?
Branch of the vagus nerve
What does the cranial laryngeal nerve give rise to?
External and internal laryngeal n.
What does the external laryngeal n. do?
Motor to the cricothyroid
What does the internal laryngeal nerve do?
Sensation from the larynx cranial to the vocal folds
Vestibular folds
Where is the recurrent laryngeal n.?
Runs cranially through the neck to approach larynx caudally
What does the caudal laryngeal n branch from?
Recurrent laryngeal n.
What does the laryngeal n. do?
Carry motor to all other muscles and sensation from caudal half of larynx
What is the function of the cough reflex?
Prevent objects from getting into the trachea
How is the cough reflex intiated?
Object touches vestibular fold
What happens when the cough reflex is initiated?
Vocal folds are tightly ADDucted to prevent further passage
What two nerves are involved in the cough reflex?
Internal and caudal laryngeal
What function does the internal laryngeal n. provide in the cough reflex?
Sensation from the larynx cranial to the vocal folds, senses the object
What happens in horses that causes problems with the dorsal cricoarytenoid muscle?
Left recurrent hemiplegia
What is deglutition?
Swallowing
What structures are involved in swallowing?
Tongue - Palate - Pharynx
What function does the soft palate have in swallowing?
Elevates to close off the nasal cavity
What function does the pharynx have in swallowing?
Approaches oral cavity and widens to receive food
What ellicits peristalsis in swallowing?
Food making contact with the pharyngeal wall