L2: Salivary glands & Swallowing Flashcards
Digestion of which macromolecule begins in the oral cavity?
Carbohydrates
What Governs Mastication?
Central Pattern Generator (CPG)
CPG is a group of neurons in the CNS that can automatically execute a complex motor act without the need for continuous sensory input
Three Phases of Mastication?
- mouth opening
- mouth closing
- intercuspal phase (occlusion)
Muscles Involved in Mastication? (opening/closing)
Closing: Temporalis, Masseter, Medial Pterygoids
Opening: Lateral Pterygoids
Nerve that translates intention to chew from the chewing center in Brain to chweing machinery?
Trigerminal Motor Nuclei
Three main pair of salivary glands and their location?
Innervation of Salivary Glands?
Sympathetic/Parasympathetic?
Parasympathetic: Trigerminalc (V), Facial (VII), Glossopharyngeal (IX)
Sympathetic:: Superior cervical ganglion
Characteristics of Parotid Salivary Gland?
Largest salivary gland primarily produces amylase. Serous cell only -> Watery Excretions
Characteristics of Submandibular Salivary Gland?
Produces ~2/3 of all saliva
Serous cells produce lysosyme
Mixed gland serous and mucus -> Watery/Mucousy Excretions
Characteristics of Sublingual Salivary Gland?
Smallest gland
Mucus excretions
Which salivary gland produces Amylase?
Parotid
Which salivary gland produces 2/3 of Saliva?
Submandibular
Which Salivary Gland Produces Lysosyme
What does this enzyme do?
Submandibular
Enzyme that catalyzes the destruction of the cell walls of bacteria
Functions of Saliva?
Functions:
• Prevention of desiccation
• Lubrication
• pH control
• Digestion
• Immunological
Composition of Saliva?
Amount produced daily?
- Water and bicarbonate
- Enzymes: Amylase, Lingual lipase, Bacterial DNAase/RNAase, Lysozyme, Immunoglobulins, Mucin
- Epidermal Growth factor- maintenance of fungiform taste buds
750mls-1500ml
Function of striated ducts of salivary glands?
Saliva from acinus is isotonic, Striated ducts make saliva hypotonic:
- lower Na+ and Cl- relative to plasma
- increase K+ and bicarbonate due to ion exchange
Dependent on the rate of secretions. Flow increases => saliva becomes more HYPERTONIC (Less Na+ Cl- Exreted)
Effects of Sympathetic vs. Parasympathetic Innervation of Salivary Glands?
Parasympathetic-> Increased volume secretion (More watery)
Sympathetic innervation -> Thickening of secretion
Papilla with highest concentration of Taste Buds?
Vallate Papilla
Papilla responsible for shaping boulus through friction?
Filiform Papilla
How is taste differentiated?
Detection of Salty Taste?
ENaC – amiloride sensitive epithelial sodium channel
Detection of Sour Taste?
Protons/H+ ions block K+ channels
Detection of Umami?
Glutamate Receptor
Detection of Bitterness
K+ channels/ G- protein coupled receptors
Detection of Sweetness
Specific G- protein coupled receptor
Muscalaris Externa transistions from ______ to ______ muscle moving down the esophagus
Muscalaris Externa transistions from skeletal to smooth muscle moving down the esophagus