HISTO LEC FINALS

• What is the digestive tract also known as?

  Gastrointestinal tract
• What are the main components of the digestive tract?

  Oral cavity, esophagus, stomach, intestines, anus
• What is the primary function of the digestive system?

  To obtain necessary molecules from food
• What is ingestion in the context of the digestive system?

  Introduction of food and liquid into the oral cavity
• What is mastication?


  Chewing food into digestible pieces
• What does motility refer to in the digestive system?

  Muscular movement of materials through the tract
• What is the mucosa in the GI tract?

  Layer with epithelial lining and connective tissue
• What does the muscularis mucosae do?


  Allows local movement of the mucosa
• What is contained in the submucosa layer of the GI tract?

  Dense connective tissue and larger blood vessels
• What is the muscularis externa composed of?

  Smooth muscle cells organized in sublayers
• What is the serosa in the GI tract?

  Outermost layer of the digestive tract
• What type of epithelium lines the oral cavity?

  Stratified squamous epithelium
• What is the function of keratinized cell layers in the oral cavity?

  Resist damage from abrasion
• What predominates in the lining mucosa of the oral cavity?

  Nonkeratinized squamous epithelium
• What is the structure of the lips (labia)?

  Core of striated muscle for mobility
• What is the internal mucous surface of the lip lined with?

  Thick, nonkeratinized epithelium
• What characterizes the vermilion zone of the lip?

  Thin keratinized stratified squamous epithelium
• What is the outer surface of the lip composed of?

  Thin skin with sweat and sebaceous glands
• What is the tongue primarily made of?

  Striated muscle
• What is the function of the tongue during mastication?

  Manipulates ingested material
• What is the sulcus terminalis?

  1. shaped groove on the tongue's surface
• What are filiform papillae?

  Numerous, elongated, keratinized structures
• What is the function of fungiform papillae?

  House taste buds and provide taste sensation
• What are foliate papillae characterized by?

  Parallel ridges on each side of the tongue
• What are vallate papillae?

  Largest papillae aligned in front of sulcus terminalis
• What do salivary (Von Ebner) glands do?

  Empty into grooves around vallate papillae
• What are taste buds?

  Ovoid structures sampling chemical composition
• How many taste buds are present on each vallate papilla?

  Approximately 250
• What is the taste pore?

  Opening where microvilli project in taste buds
• What tastant is responsible for a salty taste?

  Sodium ions
• What tastant is responsible for a sour taste?

  Hydrogen ions from acids
• What tastant is responsible for a sweet taste?

  Sugar and related compounds
• What tastant is responsible for a bitter taste?

  Alkaloids and certain toxins
• What tastant is responsible for an umami taste?

  Glutamate and aspartate
• What are dental alveoli?

  Bony sockets for teeth in the jaws
• What covers the crown of the teeth?

  Enamel
• What is dental pulp?

  Highly vascular connective tissue in teeth
• What is the periodontal ligament?

  Fibrous tissue binding cementum and bone
• What is dentin?

  Calcified tissue harder than bone
• What do odontoblasts do?

  Line the tooth pulp cavity