WHICH OF THE FOLLOWING IS ESSENTIAL AFTER FOOD IS EATEN? A CHEMICALS IN FOOD TRAVEL THROUGH SINUSOIDS B MOVEMENT OF FOOD INGREDIENTS THROUGH PORTAL SYSTEM C ENZYMATIC PROCESSING IN LARGEST ORGAN IN THE BODY D PASSAGE OF LIPIDS THROUGH DUCT IN DIAPHRAGM E ALL OF THE ABOVE
The digestive system includes the organs that ingest food, transport food, digest the food into smaller usable components, absorb the nutrients, and expel the waste products from the body.
The digestive organs collectively make up the gastrointestinal (GI) tract (alimentary canal). The GI tract organs include the oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine.
As long as food is in the long hose extending from the mouth to the anus, it is NOT technically in the body . Only when it is absorbed is it in the body.
An example is when you put your finger in the hole of a doughnut. Your finger is NOT in the doughnut. If you image your G.I. tract as an elongated doughnut , then you can see the similarity.
The accessory digestive organs do not form the long GI tube, but often develop as outgrowths from and are connected to the GI tract. These accessory organs include the teeth, tongue, salivary glands, liver, gallbladder, and pancreas
Ingestion of food that will cause atherosclerosis.
Food must be mechanically and chemically reduced before it can be absorbed across the intestinal wall.
Mouth receives food, masticates, and instigates swallowing
Mouth (oral cavity) is bounded anteriorly by the teeth and lips and posteriorly by the oropharynx. The roof is the hard and soft palates, while the floor contains the tongue and muscles covered with mucosa.
The oral cavity has two distinct regions: the vestibule (space between the cheeks or lips and the gums) and the oral cavity proper (region central to the alveolar processes of the mandible and maxillae Oral cavity proper
The lips (labia) are formed primarily by the obicularis oris. The gingivae (gums) help support the teeth. The superior and inferior labial frenulum extend from the lips to the gingivae.
The hard palate is formed by the palatine processes of the maxillae and the horizontal plates of the palatine bones. Transverse folds assist the tongue in manipulating food. The soft palate is mostly composed of skeletal muscle. The uvula and soft palate rise superiorly during swallowing to close of the nasopharynx. The palatine tonsils monitor ingested food and drink for harmful antigens.
Tongue , which is composed of skeletal muscle, assists in mastication, in swallowing, has taste buds, and helps with speech.
Lingual frenulum anchors the tongue to the floor of the mouth. Note location of submandibular salivary ducts that can squirt! Lingual
Saliva (spit) contains amylase which breaks down starch to maltose. It also contains lysozyme, and antibacterial substance.
The parotid salivary glands are the largest salivary glands and are located near the ear, partially overlying the masseter muscle. The parotid duct travels parallel to the zygomatic arch and opens into the vestibule near the second upper molar.
Swollen parotid gland in child with viral mumps . This virus can also infect the testes.
The submandibular salivary glands are inferior to the body of the mandible. A submandibular duct opens from each gland in the floor of the mouth on the lateral sides of the lingual frenulum. These are the squirters used in “gleeking”!
“ Gleeking” with submandibular gland at base of lingual frenulum
The sublingual salivary glands are inferior to the tongue. Each sublingual gland extends multiple tiny sublingual ducts that open onto the inferior surface of the oral cavity.
The facial nerve (CN VII) innervates the submandibular and sublingual glands The glossopharyngeal nerve (CN IX) innervates the parotid glands
Parasympathetic innervation stimulates salivary gland secretion (anticipation of tasty food). Sympathetic stimulation inhibits normal secretion, which is why persons who are frightened experience the sensation of a dry mouth.
A tooth has an exposed crown , a constricted neck , and one or more roots that anchor it to the jaw. The roots fit into dental alveoli where they are bound to the surrounding bone by the periodontal ligaments to form a gomphosis joint .