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Larynx

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The larynx or voice box, is a muscular tube in the throat of all mammals and some reptile and amphibians. It contains the vocal cords, which produced sound that is converted into speech and other utterances by the lips, teeth, and tongue. Birds do not have a larynx , but most have a modified portion of the wind pipe called the syrinx with which they vocalize. The larynx has several segments of firm, elastic cartilage held together by muscle and ligament. The largest segment, the thyroid cartilage, consists of two plates that form a ridge, called the “Adam’s Apple.” The larynx extend from the pharynx (throat) above the tracheae (windpipe) below. In mammals, including humans, the larynx has a flap-like structure, the epiglottis, at its inlet. The epiglottis caused swallowed food to pass from the throat into the esophagus rather than into the tracheae. The vocal cords, located in the upper region of the larynx, are two muscularized fold of mucous membrane that extend from the larynx wall.

Pancreas

A long, thin organ in humans, the pancreas has both digestive and endocrine functions and for this reason contains two completely different types of cells. Measuring about 12- 15 cm (5-6 in) long, it is nested within the curve of the duodenum and hind the stomach, in front of the spine and aorta. The digestive, or exocrine, cells of the pancreas consist of a number of organ, small lobules, or acinar cells, joined together into small ducts that, in turn, joint the two major ducts of Santorini and Wirsung, which empty through small muscular opening into the duodenum. The lobules contain numerous cells that secrete pancreatic secretion containing electrolytes and three important digestive enzymes, typsin, amylase, and lipase. The enzyme digest protein, spilt fat, break down highly polymerized nucleic acid, and break down polysaccharides such as starch, amylopectin, and glycogen. The protein splitting enzyme typsin becomes active only when the duodenal enzyme enterokinase is mixed with i

Nose

The nose, the site of the sense of smell is the organ through which mammals take in air. It is supported by cartilage and bone, covered with skin , lined with a mucous membrane, and provided with muscle. A nasal septum divides it into passages, each of which begins with a vestibule and contains a respiratory and olfactory region. The lining of the vestibule is continuous with the skin and contains hairs, sweat glands, and sebaceous (oil producing) glands . The respiratory region includes nearly all of the septum and the lateral walls of the nose. Goblet cells, which produce and secrete a watery mucus, are present in the lining, as is a type of erective tissue, composed of large, thin-walled veins whose blood supply serves to warm incoming air. The olfactory region is located on the superior concha and adjacent septum. Olfactory cells are present in its lining and have delicate, slender process (modified cilia) at their free surface. Odors from chemicals in the air are received by