Sphy102 Slay Summaries PDF
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This document provides summaries of structures, blood supply, veins, and nodes in the human body, along with detailed information on oral cavity, salivary glands, tongue, and the gastrointestinal tract. The text contains tables and lists, outlining various components and features.
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Structures Tables Skull Table Bones of the orbit : frontal, zygomatic, maxilla, sphenoid, ethmoid, lacrimal Sutures: coronal, sagittal, lambdoid Pterion: weak soft point because of meningeal artery neurocranium viscerocranium frontal...
Structures Tables Skull Table Bones of the orbit : frontal, zygomatic, maxilla, sphenoid, ethmoid, lacrimal Sutures: coronal, sagittal, lambdoid Pterion: weak soft point because of meningeal artery neurocranium viscerocranium frontal Zygomatic x2 Parietal x2 Maxilla x2 Temporal x2 mandible occipital vomer sphenoid Palatines x2 ethmoid Nasals x2 Nasal concha x2 Lacrimals x2 Skull development infant child adult elderly Large neurocranium Larger Large Smaller mandible neurocranium viscerocranium Large orbits Large orbits Adult teeth Smaller viscerocranium Thin soft bones Fused bones Varying sizes of Thinner bones paranasal sinuses Fontanelles - Infant teeth Loss of teeth unfused bones, soft, important for labour No teeth Small paranasal sinuses Blood supply, veins, and nodes ** “ - same word from above Blood supply- external Venous drainage - jugular Lymphatic drainage - carotid artery veins drain into cervical lymph nodes along internal jugular vein Superior thyroid artery Superior thyroid “ Submandibular lymph nodes Lingual “ Lingual “ Submental “ Facial “ Facial “ Cervical (superficial and deep) “ Superficial temporal “ Superficial temporal “ maxillary Maxillary “ Oral Cavity parts Oral cavity proper: basically everything inside Oral vestibule: between teeth, gums, lips, cheeks functions Passage for ingested material hold/collect ingested material prior to swallowing Begin digestion Accessory airway Articulation and resonance for speech boundaries Roof: palate Floor: muscles Walls: anterior - lips, lateral - cheeks, posterior oro-pharyngeal fauces innervation Trigeminal CN V - sensory and motor Facial CN VII - sensory Glossopharyngeal CN IX Vagus CN X Dysfunction Sensory loss - inaccurate or absent sensory feedback about placement of articulators - may not feel tongue against hard palate Motor impairment - ability to effectively move jaw for vowel and consonant production Role in Break down food to bolus swallowing Summary of Tongue: manipulates food between teeth mechanisms Palate: rough surface helps tongue manipulate Salivary glands: enzymes released Parts Mucous membrane / mucosa Lines oral cavity Continuous with mucosa of oropharynx Contains mucous glands for lubrication Called gingivae when surrounds teeth Gingivae and mucosa of hard palate and tongue or tougher than on lips and cheeks - allows for greater withstanding of abrasion from ingested material Hard Palate - anterior bony portion Consists of maxilla and palatine bones Covered with mucosa Has midline ridge called PALATINE RAPHE Has irregular folds of connective tissue called PALATINE RUGAE - extend from ant. palate to area of first premolars, highly sensitive, assist with speech and swallowing Has bony ridge called ALVEOLAR PROCESS - contains tooth sockets Innervation: maxillary CN V2 Soft Palate - posterior muscular portion **has uvula hanging from the end Innervation: maxillary CN V2 Dysfunction: produce oral sounds - soft palate closes against back of throat, if not tightly, air comes out of nose = hyper nasality Cleft Palate Birth defect when maxilla doesn’t fuse in utero Tongue 2 parts divided by SULCUS TERMINALIS CN X - taste and general sensation to epiglottis and small area of tongue near Oral part: anterior ⅔ epiglottis innervated by: CN V3 - GENERAL SENSATION, CN VII - TASTE Pharyngeal part: posterior ⅓ innervated by CN IX - TASTE & GENERAL SENSATION Anchored to floor of mouth by LINGUAL FRENULUM Lips From anterior wall of oral cavity Formed by musculo-fibrous tissue orbicularis oris muscle and labial muscles skin (external surface) mucosa (internal surface) Anchored to gingivae by LABIAL FRENULA For articulation of sound and speech, smiling, sucking liquids, holding food, osculation Innervation for UPPER LIP and TEETH: maxillary CN V2 LOWER LIP: mandibular CN V3 Cheeks / buccae From lateral walls of oral cavity - movable walls, continuous with lips Lined by mucosa Contain fat pads, muscles, nerves, duct of parotid gland Allow filling of oral vestibule Innervation: mandibular CN V3 Oropharyngeal isthmus / fauces From posterior wall of oral cavity Narrow passage between velum and tongue, boundary between oral cavity and oropharynx Bounded by faucial pillars - palatoglossal arch (ant.) , palatopharyngeal arch Palatine tonsils are located between faucial pillars, first line of defence against foreign substances Salivary Glands *produce approx. 1-1.5L *functions of saliva - Cleans and moistens oral cavity - Maintains oral hygiene, neutralises acid, antibacterial properties - Starts digestion - Mechanical: moistens food - Chemical: enzyme production - Dissolves molecules for tasting *Innervation: autonomic nervous system *Parasympathetic innervation increases salivation *sympathetic innervation decreases salivation via vasoconstriction -> resulting in thicker salivar that is rich in mucous = dry mouth Gland Parotid Submandibular Sublingual Size largest Produce most of total Smallest saliva Location Located superficially on Located deep and Located on floor of cavity, face, anterior to ear inferior to the body of under tongue mandible Type of Produces mostly serous Produces mixture of Produces mostly mucous secretions secretions serous and mucous secretions secretions Drainage Drains secretions via Drains its secretions via Drains its secretions via parotid duct into oral submandibular duct into several sublingual ducts vestibule, opposite upper oral cavity proper into oral cavity proper second molar (under tongue) (under tongue) Innervation Glossopharyngeal CN IX Facial CN VII Facial CN VII *fibres are carried to glands via branches of mandibular nerve CNV3 Tongue Components Body Central mass Tip Most anterior, motor part Important for cleansing oral cavity For swallowing, push bolus to throat Blade Posterior to tip Inferior to alveolar process of maxilla Anterior part of hard palate Dorsum Posterior to blade Inferior to posterior part of hard palate and velum Root/Base Most posterior part Surface Features Oral part (palatal surface) - Anterior ⅔: Pharyngeal part - posterior ⅓ - root tip, blade, dorsum Sulcus terminalis - division between anterior Lingual tonsil ⅔ and posterior 1/3 Foramen cecum - hole, embryological epiglottis remnant where thyroid gland came from Median sulcus - groove in midline Glossoepiglottic folds (1x median, 2x lateral) Papillae Papillae circumvallate Sit anterior to sulcus terminalis, nipple-like foliate grooves fungiform Scattered all over filiform Smaller dark spots, only one that’s for taste buds, everything else is for grip Tongue Movements CHANGE SHAPE CHANGE POSITION Shortening and elongating Elevation and depression Narrowing and widening Protrusion and retrusion Curling and flattening Lateral deviation Dysfunction Any deficit of tongue musculature due to nerve damage or surgery (head or neck cancer), impact the ability to correctly produce sounds Ex. damage on tip - difficulty producing alveolar sounds Gastrointestinal Tract Ingestion Taking food/liquids into mouth Secretion Addition of water, acids, buffers and enzymes into GI tract Mechanical Physical breakdown of food into smaller particles, mix secretions and processing move contents Motility Spontaneous motion Digestion Digestive enzymes break down large molecules to smaller - enzymatic hydrolysis Absorption Uptake of nutrients through epithelial cells into blood or lymph Defecation Elimination of wastes, indigestible substances, bacteria, dead cells Parts Oral Cavity Goal: break down food to form a bolus Mechanisms: - Mastication of food particles - Tongue manipulates food between teeth - Palate’s surface helps tongue manipulate - Salivary glands release enzymes Pharynx Goal: move bolus down - Passage way toward oesophagus Oesophagus Goal: move bolus from pharynx to stomach via peristalsis Collapsible muscular tube - Upper third consists of striated muscle - Lower ⅔ consists of smooth muscle Two sphincters - UES - upper - regulates movement into oesophagus - LES - lower - regulates movement into stomach Innervation: vagus CN X and sympathetic divisions of nervous system Stomach Storage of ingested food Very distensible - expands Muscular wall allows mechanical digestion Small Intestines Duodenum: received chyme and digestive secretions, neutralises stomach acids Jejunum: chemical digestion, more nutrient absorption Ileum: ends ar ileocecal valve sphincter Large Intestine Cecum Colon - Ascending - Transverse - Descending - Sigmoid Rectum - Anal canal - -internal and external anal sphincter Functions: - Absorption of vitamins produced by bacteria - Reabsorption of remaining water - Compaction and storage of faeces prior to defecation - Produces mucus for lubrication - motility Pharynx **for airflow, sound generation and filtering, swallowing nasopharynx oropharynx laryngopharynx Respiratory function Digestive and speech function Resonance variation Accessory airway Pharyngeal Spaces Epiglottic valleculae Pyriform sinus Depression just behind root of the tongue On either side of the laryngeal orifice is a between the epiglottis recess Saliva can pool here and is directed Internal laryngeal nerve supplies towards the pyriform sinus sensation **helps so we don’t keep swallowing when there’s saliva Gag / Pharyngeal Reflex afferent/sensory efferent/action/motor CN IX Glossopharyngeal CN IX Glossopharyngeal and CN X Vagus Stimulation of oropharynx Contraction of muscles of pharynx, soft palate and fauces Muscle Tables Muscles of Mastication (all paired) All innervated by mandibular division CN V3 Muscle Origin Insertion Action(s) Temporalis Temporal fossa Coronoid Elevates and process of retracts the mandible mandible Ramus of mandible Masseter Zygomatic arch Angle of Elevates (and mandible slightly protrudes) Lateral the mandible surface of ramus Medial pterygoid Superficial head: Medial surface of Bilaterally (both Pyramidal the ramus of the sides): elevates and process of mandible protrudes mandible the palatine bone Unilaterally (one Tuberosity of side): laterally the maxilla deviates mandible to the contralateral Deep head: (opposite) side MEDIAL surface of the lateral pterygoid plate (of the sphenoid bone) Lateral pterygoid Upper head: Neck of the Bilaterally: protrudes Greater wing condylar the mandible (and of sphenoid process of assists gravity in bone the mandible depressing the Capsule and mandible) Lower head: articular disc LATERAL of the TMJ Unilaterally: together surface of with the medial lateral pterygoid, laterally pterygoid deviates the plate (of mandible to the sphenoid contralateral side bone) Movements of TMJ Elevation & depression Superior and inferior Occurs in inferior joint hinge-like movement Protrusion and retrusion Anterior and posterior Occurs in superior joint gliding movement Lateral deviation Side to side gliding Occurs in superior Muscles of Facial Expression - paired muscles *important for non-verbal communication *contains high number of fast twitch muscle fibres *high level of control pink : upper face Yellow: middle face Blue: lower face Muscle Action(s) Occipitofrontalis Frontal belly: raises eyebrows and wrinkles forehead Occipital belly: retracts scalp *bellies connect by epicranial aponeurosis (flattened tendon) Orbicularis oculi Closes the eyes *circular muscle, sphincter = closes Procerus Depresses medial aspect of the eyebrows → produces TRANSVERSE wrinkles in the skin between them (therefore involved in frowning) *located vertically between eyebrows Corrugator Draws eyebrows inferomedially → produces supercilii VERTICAL wrinkles in the skin between them (known as the “frowning muscle”) *located deep into skin of eyebrows Levator labii Elevates the upper lip and dilates the superioris alaeque nasi nostrils *located laterally to nose and superior to lip Nasalis Transverse part (compressor naris): compresses the nostrils and also wrinkles the skin of the dorsum of the nose Alar part (dilator naris): dilates the nostrils *located across dorsum/bridge of nose Zygomaticus major Draws the angle of the mouth superolaterally (involved in smiling/laughing) *extends diagonally from syzgomatic bone *located lateral to zygomaticus minor Zygomaticus minor Elevates upper lip (involved in smiling) *extends diagonally from zygomatic bone *located medial to zygomaticus major Levator labii superioris Elevates upper lip *located superior to upper lip Levator anguli oris Elevates angle of mouth *extends superiorly from angle of mouth *zygomaticus muscles on top of it Buccinator Compresses cheeks against teeth ○ Assists with mastication ○ Sucking Forcibly expels air (e.g when laying wind instruments - “trumpet muscle”) Risorius Draws angle of the mouth laterally (“smiling muscle”) *extends laterally from angle of mouth Depressor labii Depresses lower lip inferioris *located inferior to lower lip Depressor anguli Depresses angle of mouth oris *extends inferiorly from angle of mouth Mentalis Protrudes lower lip and wrinkles the skin of the chin (“pouting muscle”) Orbicularis oris Closes the mouth Assists with mastication Involved in the articulation of bilabial and labiodental consonants ○ Bilabial = both lips ○ Labiodental = lower lip and upper teeth *not paired Platysma Tenses the skin of the neck Draws the lower lip and angle of the mouth inferolaterally Compresses the lower lip against lower teeth *located superficially on neck Muscles of the Tongue Intrinsic Muscles of the Tongue Muscle Basic attachments Action(s) Innervation Superior longitudinal Tip to base of the Shortens CNXII (Hypoglossal tongue (superior) tongue nerve) Pulls/curls tip upwards Inferior longitudinal Tip to base of the Shortens CNXII (Hypoglossal tongue (inferior) tongue nerve) Pulls/curls tip downwards Transverse From side to side of Elongates and CNXII (Hypoglossal the blade of the narrows the blade of nerve) tongue the tongue Vertical From the midline to Widens and flattens CNXII (Hypoglossal the surface of the the blade of the nerve) tongue tongue Extrinsic Muscles of the Tongue Muscle Origin (all insert into Action(s) Innervation body of the tongue) Genioglossus Genial tubercle of the Depresses, CNXII (Hypoglossal mandible (specifically protrudes and nerve) the superior mental contralaterally spine) deviates tongue Hyoglossus Body and greater horn Depresses and CNXII (Hypoglossal of the hyoid bone retracts tongue nerve) Styloglossus Styloid process Retracts CNXII (Hypoglossal of the temporal tongue nerve) bone Curls sides Stylomandibular superiorly for ligament swallowing Palatoglossus Sides of the soft palate Elevates posterior Pharyngeal branch tongue to touch the of of CNX (Vagus hard palate nerve) Suprahyoid Muscles *Swallowing: these muscles elevate the hyoid bone in the pharyngeal and esophageal phases, which causes the epiglottis to fold over the entrance to the larynx → prevents food from entering airway Muscle Origin Insertion Action(s) Innervation Mylohyoid Mylohyoid line Body of the Elevates the hyoid CNV3 (Mandibular of the mandible hyoid bone bone and the oral branch of the cavity trigeminal nerve) Geniohyoid Genial tubercle Body of the Elevates the hyoid C1 spinal nerve, of the mandible hyoid bone bone and pulls it via CNXII (specifically the anteriorly (hypoglossal inferior mental nerve) spine) Stylohyoid Styloid process Body of the Elevates the hyoid CNVII (facial of the temporal hyoid bone bone and pulls it nerve) bone posteriorly Digastric Anterior belly: Body of the Elevates Anterior belly: digastric fossa hyoid bone (via the hyoid CNV3 (Mandibular of mandible the intermediate bone branch of the tendon) Depresses trigeminal nerve) Posterior belly: the mastoid notch mandible Posterior belly: of temporal against CNVII (facial bone resistance nerve) Muscles of the Velum/Soft Palate Muscle Action(s) Innervation Levator veli palatini Elevates velum to meet posterior Pharyngeal branch of pharyngeal wall CNX (vagus nerve), via the pharyngeal plexus Musculus uvulae Elevates and shortens uvula Pharyngeal branch of CNX (vagus nerve), via the pharyngeal plexus Palatoglossus Depresses velum (draws it onto Pharyngeal branch of the tongue) CNX (vagus nerve) via the pharyngeal plexus Palatopharyngeus Depresses velum Pharyngeal branch of Elevates pharynx CNX (vagus nerve) via the pharyngeal plexus Tensor veli palatini Tenses velum CNV3 (Mandibular Opens auditory tube during branch of the trigeminal swallowing and yawning nerve) Muscles of the Pharynx **regulates size and shape of tube for speech and swallowing **works in conjunction with oral cavity, tongue, epiglottis Muscle Action(s) Innervation Superior pharyngeal Narrows upper Pharyngeal branch constrictor pharynx of vagus (CN X) Help us get food pharyngeal plexus from mouth to throat (CN IX and CN X) Help prevent food and liquid to wrong spaces Middle pharyngeal Narrows middle Pharyngeal branch constrictor pharynx of vagus (CN X) pharyngeal plexus (CN IX and CN X) Branches of external and recurrent laryngeal nerve (vagus nerve) Inferior pharyngeal Narrows lower Same as middle constrictor pharynx pharyngeal *most powerful of the three Maintains closure of constrictor UES Palatopharyngeus Raises/elevates Pharyngeal branch pharynx of vagus nerve (CN Mix of pharyngeal When velum is X) and soft palate relatively stable, Pharyngeal plexus muscle contraction of pp (CN IX and CN X) results to: uppermost fibres of the muscle draw the lateral pharyngeal walls inward to complement superiors lowermost pull upward and elevate pharynx Salpingopharyngeus Raises pharynx Same as Opens auditory tube palatopharyngeus Reduces width of (and superior pharynx pharyngeal constrictor) Stylopharyngeus Raises/elevates Glossopharyngeal pharynx nerve (CN IX) Originates at styloid Pulls pharyngeal process of temporal tube upwards and bone outward widening Inserts into lateral wall of pharynx and thyroid cartilage Sensory innervation of the pharynx IX - glossopharyngeal transmits information on touch, temperature and pressure from oropharyngeal/upper pharynx mucosa posterior 1/3 of tongue, palatine tonsils, oro, mucosa of middle ear, pharyngotympanic tube and mastoid air cells, carotid body X - vagus transmits information on touch, pressure and temperature from the pharynx and larynx Three branches of CN X supply the laryngopharynx: pharyngeal: supplies mucosa overlying the levator veli palatini and superior and middle pharyngeal constrictors internal branch of the superior laryngeal: nerve supplies the hypopharynx, epiglottis, supraglottic laryngeal structures (ventricle, fvf, arytenoids, laryngeal aspects of aryepiglottic folds and vestibule) recurrent: supplies subglottic larynx and inferior pharyngeal constrictor **longitudinal muscles NERVE TABLE Nerve Innervation Nerve Region Innervated CN V Trigeminal Ophthalmic nerve of (V1) Face: Sensory innervation of forehead, upper eyelids, nose dorsum CN V Trigeminal Maxillary nerve of (V2) Face: Sensory innervation of lower eyelids, ala of nose/nasal tip, temporal bone, cheek/zygomatic bone Oral cavity: - Hard palate - Upper lip and teeth CN V Trigeminal Mandibular division of (V3) Muscles of mastication temporalis, masseter, medial pterygoid, lateral pterygoid Face: Sensory innervation of chin, lower lip, cheek etc. Oral cavity: - Lower lip and teeth - Buccal mucosa - Anterior ⅔ of tongue Tongue sensory: - General sensation to anterior ⅔ of tongue Velum: - Tensor veli palatini CN VII Facial Nerve Salivary glands: Submandibular and sublingual glands > sympathetic innervation = decreased salivation > parasympathetic innervation = increased salivation Tongue: - Taste to anterior ⅔ of tongue All muscles of facial expression - motor CN IX Glossopharyngeal Nerve Salivary glands: Parotid gland Tongue: - Taste and general sensation to posterior ⅓ of tongue (incl. Pillars of fauces) Pharynx: - Sensory: transmit info on touch, temp, pressure from oropharyngeal/upper pharynx mucosa. > helps w stimulation of oropharynx for gag reflex - Motor: Pharyngeal muscles innervated by motor fibres of CN IX (along w vagus nerve) > helps w contraction of pharyngeal muscles, soft palate and fauces for gag reflex CN X Vagus Nerve Tongue: - Taste and general sensation to small areas of tongue near epiglottis - And epiglottis Tongue muscle: - Palatoglossus Velum: - All palatine muscles innervated by vagus nerve through pharyngeal plexus - Except tensor veli palatini Gastrointestinal tract - Innervates oesophagus (along w the sympathetic divisions of NS) Pharynx - Pharyngeal plexus/Motor fibres innervate pharyngeal muscles Laryngopharynx (sensory innervation) Transmit info on touch, pressure, temp from pharynx and larynx 1. Pharyngeal branch: supplies the mucosa overlying the levator veli palatini and superior/middle pharyneal constrictors 2. Internal branch of superior laryngeal: supplies laryngopharynx, epiglottis, supraglottic laryngeal structures (eg. false VF, arytenoids, aryepiglottic folds, vestibule etc.) 3. Recurrent laryngeal branch: subglottic larynx and inferior laryngeal constrictor CN XI Accessory Pharynx: - Contributes some fibres to the vagus nerve - Indirectly contributes to the pharyngeal musculature CN XII Hypoglossal Nerve Tongue muscle: All extrinsic and intrinsic tongue muscles except palatoglossus Cranial Nerves Cranial Nerve Function CN I Olfactory SVA: Sense of smell CN II Optic SSA: Vision, sends visual messages to brain CN III Oculomotor GSE: eye movement GVE: Pupil width Most voluntary/involuntary eye movement eg. elevation of eyelid CN IV Trochlear GSE: moves eye medially (toward nose) and downwards CN V Trigeminal Has 3 branches: Ophthalmic (sensory) Maxillary (sensory) Mandibular (mixed) CN VI Abducens GSE: Moves eye and abducts eye CN VII Facial Mixed cranial nerve GSE: facial muscle expression / lip movement GVE: Glands–submandibular and sublingual salivary glands and tear glands SVA: anterior ⅔ of tongue taste GSA: Posterior ear canal CN VIII Vestibulocochlear SSA: Helps with hearing (cochlea) and balance (vestib) CN IX Glossopharyngeal GSA: taste sensation in posterior oral cavity SVA: taste from posterior tongue GSE: stylopharyngeus GVE: parotid gland CN X Vagus GSE: movement of larynx, pharynx, velar muscles GVE: parasympathetic control of abdominothoracic viscera muscles SVA: taste from pharyngeal region GVA: sensation from laryngopharynx and larynx CN XI Accessory GSE: Movement of certain neck muscles CN XII Hypoglossal GSE: Movement of tongue muscles Sensory vs Visceral Sorry guys im too lazy to write it i’ll just copy and paste the info from the worksheet HAEHWDJNE PROCESSES Swallowing Oral phase = voluntary Pharyngeal phase = reflexive/involuntary Oral - voluntary Pharyngeal - Oesophageal reflexive/involuntary Lasts for 3 seconds or Triggered once bolus Lasts between 8-20 longer passes anterior faucial sesconds pillars From open and depressed - Rapid complex movements Movement of bolus into lip sealed (CNVII) and simultaneously to move oesophagus mandible elevated (CNV3) bolus Mastication of solids (CNV3) Full velopharyngeal Bolus is propelled through closure:velum elevation and oesophagus by peristaltic pharyngeal walls constrict actions of the oesophageal walls Anterior pulling of soft palate Elevation of hyoid bone: Peristaltic contraction raises (CNX - palatoglossus elevates larynx, folds over pressure behind the bolus, muscle) to rest against the epiglottis creating the pressure back of the tongue CNXII differential needed to propel which is elevated serving to it toward the stomach keep material in the oral cavity Tongue sweeping CNXII Laryngeal closure CN X Relaxation of the lower oesophageal sphincter to allow material to pass into the stomach Sensation in oral cavity Opening of upper CNV, V2, V3, VII, IX, esophageal sphincter Tongue root moves backward Movement of bolus: as bolus passes the anterior faucial arch pharynx is drawn upwards (to receive/catch bolus) constriction of pharynx by sequential peristaltic (squeezing) action to cause downward movement of bolus towards oesophagus relaxation of the cricopharyngeal sphincter (or UES) to allow material to pass from pharynx into oesophagus Variables Affecting Swallow - Bolus: consistency, texture, volume, taste - Body position - Development - Ageing - Sex - breathing KEY __ = CN V3 __ = CN VII __ = CN CNIX __ = CN X __ = CN XII Structure Oral Preparatory Phase Oral Transport Pharyngeal Phase Esophageal Phase Phase Lips Sealed Sealed Sealed Sealed Mandible Elevated Mandible remains Mandible remains Mastication of solids elevated elevated occurs (muscles of mastication move mandible) Tongue Elevates against soft Tip elevates Tongue root moves palate - keeps Pushes bolus backwards material in the oral against the cavity palate and Sweeps to move food towards the and clear it from the back of the oral cavity mouth Velum Depressed to rest against the Tilts up and back to Elevates for back of the tongue close off the pathway velopharyngeal closure to the nasal cavity and - closes off nasal cavity direct bolus towards so food/liquid does not the oesophagus enter the nasal cavity Pharynx Elevates/is drawn upwards to catch the bolus once it passes the anterior faucial arch Muscles of the pharynx constrict (peristalsis) to move bolus down toward the oesophagus Hyoid bone Elevated by the suprahyoid muscles, which elevates the larynx Epiglottis The elevation of the Folded over larynx causes the epiglottis to fold over the larynx, preventing any food/liquid from entering the larynx and going into the trachea and lungs (airways) Vocal folds The lateral cricoarytenoid and transverse + oblique arytenoid muscles adduct the vocal folds to prevent materials from entering the airway Upper Relaxes and opens to esophageal allow material to pass sphincter from pharynx into the oesophagus Lower Relaxes and opens to esophageal allow material to pass sphincter into stomach Oesophagus Moves bolus to the stomach through peristalsis (wave-like contractions of muscles): - Muscle contracts - Pressure behind bolus increases - Relaxation lowers pressure in front of the bolus - This creates a pressure gradient which helps propel the bolus towards the stomach