Unit 5 Learning ObjectivesDigestive System Learning ObjectivesThe student should be able to do the following activities at the end of this unitPart 1Be able to classify an organ as part of the GI tract vs. accessory organ- GI Tract Organs o Oral cavityo Pharynxo Esophaguso Stomacho Large intestineo Small intestineo Anus- Accessory organso Teetho Tongueo Salivary glandso Livero Gallbladdero Pancreas Know in what organs do the processes of ingestion, digestion, absorption, metabolism and defecation occur. Ex., the tongue, teeth, stomach and intestines are the structures/organs for mechanical digestion.- Mechanical digestiono Mouth = masticationo Stomach and intestines = Smooth muscle contraction (GI motility) - Chemical digestiono Mouth = amylase in salivao Stomach = trypsin, gastrin, pepsino Intestines = numerous enzymes- Absorption o Enterocytes of intestines - Metabolism o Liver = major processing organ - Defecation o Terminal colon (large intestine)Review the difference between the thoracic and abdominopelvic cavity and between the abdominal vs. pelvic cavity. What are the boundaries of each of these cavities?Know the planes that create the 9 abdominal surface regions. 1- Thoracic cavityo Superior to diaphragm - Abdomnopelvic cavityo Inferior to diaphragm o There are 9 regions that are formed by the intersection of two transverse planes and twosagittal planes Right hypochondriac region Epigastric region Left hypochondriac region Right lumbar region Umbilical region: appendix is here Left lumbar region Right iliac region Hypogastric region Left iliac region o Midclavicular planes run verticleo Subcostal Plane runs horizontal and is higher up than Supracristal Plane which also runs horizontal o Abdominal cavity is superior to pelvic brimo Pelvic cavity inferior to pelvic brimKnow the planes that create the 4 abdominal quadrants. Be able to locate in what quadrant the majorityof an organ would be located. Ex., most of the stomach is in the LUQ. You will see some overlap in the CP for each organ.- Right Upper Quadrant: right kidney and gallbladder here- Left Upper Quadrant: spleen and left kidney and stomach are here- Right lower Quadrant: vermiform appendix are here - Left lower Quadrant: small intestine here- Transumbilical Plane is horizontal - Medical plane is vertical- The uterus will occupy all 4 quadrants in late gestation Be able to define the peritoneal cavity vs. the abdominal cavity? What is the difference? What is the contents of the peritoneal cavity?- The peritoneal cavity is within the abdominalpelvic cavity. It is between visceral and parietal peritoneum. It contains peritoneal fluid. It is “potential space”- Abdominal cavity is made up of peritoneal cavity and visceral peritoneum and parietal peritoneum. Know the 4 layers of the GI tract tissue from deep to superficial or vice versa. Know briefly the function of each layer. Which layers have nervous innervations and/or lymph tissue? The emphasis is not on the histology of these layers.2- From Deep (luminal)o Mucosa Lining of lumen Composed of 3 layers Contains lymphatic tissue o Submucosa Highly vascularized connective tissue Submucosal enteric neural plexus that controls GI secretions and localized blood flow Contains many glands which open into the lumen by way of ducts Contains lymphatic tissue o Muscularis Two types of muscle tissue in GI Tract Skeletal muscle tissue - At very beginning and end- Voluntary motor control- Mouth, pharynx, upper esophagus and ext. anal sphincter Smooth muscle tissue- Found in the remainder of the GI tract- 2 layers (Stomach has 3 layers)o Circular (inner): contraction produces change in diameter of segment Peristalsiso Longitudinal (outside): contraction produces change in length ofsegment Segmentation - Contains the portion of the enteric neural plexus responsible for GI motilityo Serosa (aka visceral peritoneum) Secretes serous peritoneal fluid Serosa is absent in oral cavity, pharynx, esophagus, and distal rectum. - To Superficial (aluminal)Part 2Know the processes of digestion that occur in the oral cavity, and the boundaries of the oral cavity.***Function as organs of mastication, and provide the initial stage of mechanical digestion.Boundaries- Anterior: inner surface of lips3- Lateral: cheeks- Superior: hard palate and soft palate- Inferior: floor of mouth- Posterior: fauces, open to oropharynxIdentify tooth anatomy: crown, dentin, periodontal ligaments, and alveolus. - Crown: enamel part of tooth; washed by saliva- Dentin: softer part of tooth underneath crown- Periodontal ligaments: anchors teeth; extends from dentin to alveolar bone- Alveolus: groove in maxilla and mandible that holds tooth. o The tooth is held inside the alveolus by a gomphosis joint!Know the difference between deciduous and permanent teeth. What are the tooth types for each? Howmany deciduous and permanent teeth does an individual have? - Deciduous (baby teeth) has 20 teeth while permanent teeth has 32 teetho 4 Quadrants, each has 5 teetho 1 Central incisor, 1 lateral incisor, 1 canine, 2 molars- Permanent teeth have 3 molars instead of 2 and have 2 premolars. o 4 Quadrants, each has 8 teetho 1 Central incisor, 1 lateral incisor, 1 canine, 2 premolars, 3 molarsWhen do permanent teeth first start to erupt? Understand the GSA innervations of the teeth, and the difference between maxillary and mandibular teeth innervation.- Begin to erupt at 6 years of age. - Maxillary teeth are innervated by superior alveolar n. of CN V2- Mandibular teeth are innervated by inferior alveolar n. of CN V3Understand the anatomy of the tongue, notice that the 4 extrinsic tongue mm. all end in –glossus. Distinguish the difference in the innervations of the posterior 1/3 vs. anterior 2/3 of the tongue for taste and general sensation. What is the motor innervation to the extrinsic tongue mm.?- Intrinsic muscleso Alters size and shape: responsible for precise movements during speech productiono Assists with mastication by placing food between the teeth- Extrinsic muscleso GENIOglossus: underneath tongue and most anterioro STYLOglossus: o HYPOglossuso PALATOglossuso Protrude (protract), retract, depress and elevate the tongueo Contraction of these muscles assists in swallowing 4- Anatomyo Triangular in shapeo The base of the tongue is the portion that is attached.o Bodyo Tip—freely mobileo Sulcus terminalis: divides the tongue
View Full Document
Unlocking...