What is the digestive tract and what does it include?
Tube extending from mouth to anus
- mouth, pharynx, esophagus, small and large intestine
What makes up gastrointestinal tract?
Stomach and intestines only
What are the Accessory organs?
Teeth, Tongue, salivary glands, Liver, Gallbladder, and Pancreas
What are Mesenteries?
- Connective Tissue Sheets
- Loosely suspend stomach and intestines to abdominal wall
- Hold abdominal viscera in proper relationship
- Prevent small intestine from becoming tangled
- Provide passage for blood vessels and nerves supplying tract
What are some mouth functions?
Ingestion, Taste, Chewing, Mechanical/Chemical digestion, Swallowing, Speech, and Respiration
What tissue lines the mouth?
Stratified Squamous Epithelium
What tissue covers the tongue?
Nonkeratinized Squamous Epithelium
What does the Palate do?
Separates oral cavity from the nasal cavity
What are the parts of the palate?
Hard Palate –> Anterior Portion; consists of horizontal plates of maxillae and palentine bones; covered by mucous membrane
Soft Palate –> Posterior portion; spongy with glandular tissue and skeletal muscle
- Uvula –> conical projection at rear
What is the function of Dentition (Teeth) ?
Break food into smaller pieces –makes it easier to swallow and speeds up chemical digestion
From the midline to the rear what are the kinds of teeth?
2 incisors (bite off food), canine (punctures and shred it), 2 premolars and up to 3 molars (crush, shred, and grind food)
What are the regions of the tooth?
Crown –> portion above the gingiva (Gum)
Root –> Portion in tooth socket below the gum
What is Dentine?
- Hard living connective tissue in calcified matrix
- Composes most of tooth
- CAN Regenerate if damaged
What is Enamel?
- Non-living hardened secretion
- Covers Dentine in Crown
- CANNOT regenerate
What is Cementum?
- Covers tooth root
- Living connective tissue
- cells embedded in calcified matrix
- can regenerate if damaged
What is pulp?
- Loose connective tissue, blood, lymphatic vessels, and nerves
- occupy crown internally and root canal in root
What is saliva and what are it’s functions?
- Watery solution of mucus, enzymes, and electrolytes
- FUNCTIONS: Moistens mouth, cleanses teeth, inhibits bacterial growth and dissolves molecules, and lubricates food and binds particles
What are the 3 Salivary Glands?
Parotid Glands –> just beneath skin, anterior to ear lobes
Submandibular Glands –> Along medial side of mandible body
Sublingual Glands –> Located in floor of mouth
What does the Pharynx do?
Connects oral cavity to the esophagus
connects nasal cavity to larynx
The Pharynx consists of 2 layers what are they?
- deep layer of longitudinal skeletal muscle
- superficial layer of circular skeletal muscle (force food downward when swallowing)
What is the stomach and what does it do?
- muscular sac in upper left abdominal cavity
- Food storage unit
- breaks up food particles
- liquifies food
- begins chemical digestion of proteins and fat
- Produces semi digested food, “chyme”
What are the 4 stomach regions?
- Cardiac Region –> immediately inside cardiac orifice
- Fundic Region –> Superior dome nestling against diaphragm
- Body –> Greatest part of stomach distal to cardiac orifice
- Pyloric Region –> Narrower pouch at inferior end. Terminates at pylorus (narrow passage into duodenum). surrounded by pyloric sphincter
What is the Liver?
- Gland immediately inferior to diaphragm
- Fills most of right hypochondriac and epigastric regions.
- Body’s larges gland weighing 3 lbs
What are the 4 lobes of the Liver?
Left, Right, Quadrate, and Caudate
