Lecture 11: Mouth & Esophagus Flashcards
What are the two groups of organs in GI system?
- alimentary
- accessory (breakdown)
What are the six steps of dissasembly?
- ingestion
- secretion
- motility
- digestion
- absorption
- defecation
What are the functions of teeth, cheek, uvula, submandibular gland?
Teeth: mech. digestion
Cheek: containment
Uvula: tactile/irritant receptors
Gland: chemical digestion
What are the two dentitions? Four types of teeth/purpose?
Dentitions: deciduous, permanent
Teeth: incisors (cutting), canines (tearing), premolars (crushing), molars (grinding)
What are the three layers of the crown (tooth)? What are their purposes?
Enamel: calcium salts protecting tooth from wear & tear
Dentin: calcified CT, makes up majority of tooth
Gingiva: gum, holds tooth
What is within the neck (tooth)?
Pulp cavity: CT containing Ns and BVs
What 5 things are contained within the root (tooth)?
Cementum: bone-like, attaches root to periodontal ligament
Root canal: extension of pulp cavity, contains Ns and BVs
Alveolar bone
Periodontal ligament: anchors tooth to bone
Apical foramen: opening at base of root canal, BVs, LVs, Ns enter tooth
What are the three branches of the trigeminal nerve, and what is it responsible for?
Ophthalmic, maxillary, mandibular. Muscles of mastication, mouth sensory
What are the four extrinsic tongue muscles, how do they act on the tongue? What nerve innervates them?
Palatoglossus: elevation
Genioglossus: protraction
Hyoglossus: depresses
Styloglossus: elevation
Hypoglossal supplies all but palatoglossus (vagus N)
Which muscles are responsible for closing of mouth? Lateral movement? Which N is responsible?
Closing: temporalis, masseter
Lateral: temporalis, lateral pterygoid, medial pterygoid
All trigeminal N.
What are the three glands for chemical digestion, where are they generally located?
Parotid gland: by ear
Submandibular gland: by jaw
Sublingual gland: under tongue
Which 6 substances are found in saliva, and what do they generally do?
Amylase: break down starches
Lipase: break down fats
Mucin: protect/lubricate
Lysozyme: antimicrobial
IgA: antibody
Bicarbonate: buffer
What occurs in para vs. sympathetic salivation?
Para = watery, enzyme-rich
Symp = thicker, mucous-rich
How does taste “get” to the brain, depending on location of the tongue? Where does it go?
Front 2/3: Facial N
Back 1/3: Glossopharyngeal N
Throat: Vagus N
**Tactile sensation: Trigeminal N
Tongue –> thalamus –> gustatory cortex
What occurs in the three phases of deglutition (swallowing)?
Oral: bolus moves backwards, voluntary
Pharyngeal: Soft palate closes, UES opens/relaxes, epiglottis blocks larynx
Esophageal: UES contracts, peristalsis, LES relaxes
What are the 4 layers of esophagus, deepest to superficial? (hint: 2 sub-layers at 3rd layer)
Mucosa
Submucosa: nerves, vessels
Muscularis (1. circular, 2. longitudinal): peristalsis
Adventitia: connective tissue anchor
Lingual lipase is activated in ______ environments. Which organ is it activated in?
Acidic, stomach
Which nerve is found in the pulp cavity? Which part of the tooth is that?
Trigeminal. Neck of tooth.
The mucosal epithelium of the stomach detects changes in ________ and ______
pH, stretch
