oesophagus Flashcards
describe the topography of the oesophagus
dorsal to the larynx, follows trachea down the neck, inclines left, regain median position above trachea before/ just after entering the thorax.
passes tracheal bifurcation over the heart
penetrates the oesophageal hiatus of the diaphragm
passes the dorsal border of the liver
joins the stomah cardia
what is the outer coat of the oesophagus
loose connective tissue (adventitia) to connect it with neighbouring structures
replaced by serous in abdomen and thorax
what seperates the submucosa and mucosa
fenestrated muscularis mucosa
what cells line?
stratified squamous (sometimes kertianised for diet)
what innervated the oesophagus
vagus nerve
sympathetic nerve
glossopharyngeal
what are the histological layers in the tubular organs (inside out)
tunica mucosa
tunica submucosa
tunica muscularis
(tunica serosa is organ is suspended in the body cavity)
tunica adventitia
which histological layer are glands present
submucosa
what are the layers of tunica mucosa
laminae epithelialis
lamina propria (connective tissue)
lamina muscularis mucosa (smooth)
describe the muscle
longitudinal and circular
what process occurs in the oesophagus
deglutition (swallowing)
describe the process of involuntary swallowing
breathing stops
soft palate elevates to move the epiglottis
tongue pushes against the hard palate
glottis is pulled under epiglottis
pharynx closes causing a wave of muscle contraction
oesophageal sphincter relaxes
what is the oesophagus like at rest
relaxed with constricted sphincter to maintain pressure to prevent collapsing
longitudinal muscles are relaxed, circular are contracted