A period of time in which all factors of production and costs are variable. In the long run, firms are able to adjust all costs, whereas in the short run firms are only able to influence prices through adjustments made to production levels.Additionally, whereas firms may be a monopoly in the short-term they may expect competition in the long-term.ong-Run Average Total Cost-LRATC. Firms examining the long run understand that they cannot alter levels of production in order to reach an equilibrium between supply and demand.
In the embryonic development of vertebrates, pharyngeal pouches form on the endodermal side between the pharyngeal arches. The pharyngeal grooves (or clefts) form the lateral ectodermal surface of the neck region to separate the arches.The pouches line up with the clefts, and these thin segments become gills in fish.n the embryonic development of vertebrates, pharyngeal pouches form on the endodermal side between the pharyngeal arches. The pharyngeal grooves (or clefts) form the lateral ectodermal surface of the neck region to separate the arches.
The pharynx is the cavity at the back of the mouth. It is located behind the mouth and the nasal cavity the esophagus and the larynx. The human pharynx is comprised of three sections: (1) the nasopharynx, (2) the oropharynx, and (3) the laryngopharynx. The laryngopharynx is the caudal part and the largest part of the pharynx. It is found below the oropharynx, and inferior to the epiglottis. It connects to the esophagus posteriorly.