Name and describe the main the cartilaginous skeleton of the larynx and the position of the vocal cord in relation to the palpable landmarks. Relate laryngeal structure to function and innervation. Explain the movement of the vocal cords through muscle actions. Identify and describe the main structures and parts of the pharynx. Name the muscles of the pharyngeal wall.
The Pharynx
fibromuscular tube which extends from the base of the skull to the lower border of the cricoid cartilage C6
pharyngeal raphe
a cord - like ligament extends from the phrayngeal turbecle on the base of the skull to the level of the cervical vertebra C6
muscular walls of the pharynx are comprised of an outer layer made up of 3 constrictors
the SUPERIOR, MIDDLE and inferior PHARYNGEAL CONSTRICTORS
The inner muscular layer of the pharynx is made up of 3 small longitudinally
STYLOPHARYNGEUS, PALATOPHARYNGEUS, salpingopharyngeus
STYLOPHARYNGEUS origin
outside of the pharynx, from the styloid process, and gains access to the interior of the pharynx by passing between the superior and middle constrictors
PALATOPHARYNGEUS origin
from the soft palate, and runs down the length of the pharynx, intermingling with fibres of the stylopharyngeus below the inferior border of the superior constrictor
SALPINGOPHARYNGEUS
usually considered as a slip of palatopharyngeus which has a separate origin from the posterior part of the cartilage at the opening of the auditory tube (salpinx=tube
During swallowing, successive contraction of the superior, middle, and inferior constrictor muscles helps to
to propel the bolus (ball) of food down into the oesaphagus
, contraction of the 3 longitudinal muscles of the pharynx helps to
raise the pharynx, effectively aiding it in engulfing the bolus of food.
In between acts of swallowing, the lowest fibres of the inferior constrictor are thought to act as
spchinter,guarding the entrance to the oesophagus
The LARYNX
apparatus made up of cartilage, ligaments, muscles, and mucous membrane, which guards the entrance to the lower respiratory passages (trachea, bronchi, and lungs) and houses the vocal cords
Cricoid Cartilage
ring of hyaline cartilage that forms the inferior wall of the larynx. It is attached to the top of trachea
elevation of the larynx
causes the epiglottis to move down and form a lid over the glottis, closing it off
Corniculate Cartilage
Horn-shaped pieces of hyaline cartilage located at the apex of each arytenoid cartilage.
Cuneiform Cartilage
Club-shaped pieces of elastic cartilage located anterior to the corniculate cartilages
boundaries formed by the vestibular and vocal folds divide the cavity of the larynx into three parts
1)the vestibulewhich is the area above the vestibular fold
2)the ventricle.which is a pocket-like recess between the vestibular and vocal folds on both sides.
3)infraglottic cavity,area below the vocal folds.
2)the ventricle.which is a pocket-like recess between the vestibular and vocal folds on both sides.
3)infraglottic cavity,area below the vocal folds.
MUSCLES OF THE LARYNX
1)cricothyroid muscles-regulate tension of vocal cords
2)muscles which open rima glottidis
2)muscles which open rima glottidis
Oblique arytenoid muscles
narrow the laryngeal inlet by constricting the distance between the arytenoid cartilages.
function of Cricothyroid Muscle
1)Pulls the thyroid cartilage forward, increasing the distance between the thyroid and arytenoid cartilages
2)Tenses the vocal cord
2)Tenses the vocal cord
Lateral Cricoarytenoid Muscle
-Draws the muscular process of the arytenoid cartilage anteriorly, which
-pivots the arytenoid cartilage and
-adducts. the vocal folds
-pivots the arytenoid cartilage and
-adducts. the vocal folds
Most of the muscles of the larynx receive their innervation via
the RECURRENT LARYNGEAL BRANCH of the vagus nerve
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