The Esophagus, casually known as the food funnel or neck, is an organ in vertebrates through which food passes, supported by peristaltic compressions, from the pharynx to the stomach. The throat is a fibro muscular tube, around 25 cm (10 in) long in grown-ups, which goes behind the trachea and heart, goes through the stomach and purges into the highest locale of the stomach. During gulping, the epiglottis inclines in reverse to keep food from going down the larynx and lungs. The mass of the throat from the lumen outwards comprises of mucosa, sub mucosa, layers of muscle filaments between layers of sinewy tissue, and an external layer of connective tissue. The mucosa is a defined squamous epithelium of around three layers of squamous cells, which differentiations to the single layer of columnar cells of the stomach. The vast majority of the muscle is smooth muscle in spite of the fact that striated muscle prevails in its upper third. It has two strong rings or sphincters in its divider, one at the top and one at the base. The lower sphincter assists with forestalling reflux of acidic stomach content. The throat has a rich blood gracefully and venous waste. Its smooth muscle is innervated by automatic nerves and likewise intentional nerves which are conveyed in the vagus nerve to innervate its striated muscle.