Mouth, pharynx, larynx and neck

Examine the salivary glands in the image to the right. Remember that the salivary glands are exocrine glands which release saliva into the mouth via salivary ducts. Saliva contains the digestive enzyme amylase, which begins the breakdown of carbohydrates.

Next, the organs of the mouth and pharynx were exposed by inserting a pair of scissors in the angle of the lips on the side not previously dissected, and cutting posteriorly as shown below.

The incision followed the curvature of the tongue, so that the roof of the mouth was not cut, and continued until the little flap of tissue (the epiglottis) was visible. The floor of the mouth and pharynx was then swung open.

Note major landmarks such as the teeth (some may have emerged through the gums, while others may form bulges beneath) and tongue. Look for papillae (taste buds) on the tongue. Examine the roof of the mouth. The anterior part of the roof is called the hard palate because it consists of cartilage and bone with a covering of epithelium. The posterior part of the roof of the mouth is called the soft palate. This part of the palate is comprised of muscle and connective tissue. Dorsal to the hard palate are the paired nasal cavities. The nasal septum separates the right and left cavities. You will not be able to see the nasal cavities on your pig. Posteriorly, the nasal cavities are continuous with the pharynx.

The pharynx is the region at the back of the mouth which is shared by the digestive tract and the respiratory system. The pharynx is divided into three regions: an oral pharynx posterior to the mouth cavity and ventral to the soft palate; a nasal pharynx dorsal to the soft palate, and a laryngeal pharynx posterior to the tongue, where the oral pharynx and nasal pharynx come together.

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