Chapter 26: Digestive System Flashcards
Parts of the gastrointestinal tract (alimentary canal)
-food and waste
-food and saliva
-chyme
-digestive organs
-accessory digestive organs
what does food and saliva result in?
bolus
what is chyme?
paste-like material in stomach
what is the gastrointestinal tract?
pathway by which food enters the body and solid wastes are expelled
what does the gastrointestinal tract include?
includes the oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, and anus
functions of the digestive system
-ingestion
-digestion
-secretion
-absorption
-elimination
2 types of digestion
-mechanical digestion
-chemical digestion
what is mechanical digestion?
-physical breakdown
-mastication = chewing
what is ingestion?
first step in the process of digestion and refers to the act of taking food and liquids into your mouth
what is digestion?
process by which the body breaks down the food you eat into smaller, more absorbable molecules.
what is chemical digestion?
-enzymes
-smaller molecules
what is secretion?
process of releasing digestive juices, enzymes, and other substances that aid in breaking down food so that nutrients can be extracted from it
what is absorption?
-process of taking the broken-down nutrients from digested food and delivering them into the body’s circulation system so they can be used to maintain and support various physiological functions.
-primarily takes place in small intestine
what is elimination?
-final stage of digestive process where it helps rid the body of waste and toxins
-primarily take place in large intestine
Parts of the oral cavity
-mouth
-lips to oropharynx
-hard palate & soft palate
-mylohyoid (forms floor of mouth)
-vestibule (outside teeth to lips)
-oral cavity proper (b/t teeth)
what is the biggest muscle in the oral cavity?
tongue
what type of muscle is the tongue?
skeletal muscle
parts of the tongue
-body
-root (lingual tonsil)
-lingual frenulum (tip to the floor of the mouth)
-papillae (superior surface)
functions of the tongue
-sound production
-food manipulation
-swallowing
what is the papillae?
tiny raised protrusions on the tongue that contain taste buds
4 types of papillae
-filiform
-fungiform
-vallate (back of the tongue)
-foliate (edge of the tongue)
which type of papillae has no taste buds and is bristle-like?
filiform
what is the largest part of the tongue?
vallate
functions of saliva
-moistens food
-cleans mouth
-inhibits pathogen growth
-salivary amylase starts digestion
types of salivary glands
-intrinsic
-extrinsic
function of intrinsic gland type
minor salivary gland that continually secrete small amounts of saliva to help maintain oral moisture
function of extrinsic gland type
major salivary gland that are responsible for producing most of the saliva during eating
features of intrinsic gland type
-small
-lingual lipase
-around oral cavity
features of extrinsic gland type
-larger
-multicellular
-pairs
-outside oral cavity
-amylase in saliva
3 types of extrinsic salivary gland types
-parotid glands
-submandibular glands
-sublingual glands
features of parotid glands
function: They produce a watery, enzyme-rich saliva that primarily helps with the initial breakdown of starches
-largest
-anterior to ear, lateral to masseter
-parotoid duct
-empties lateral, superior
features of submandibular glands
function: They produce a mixture of mucus and enzymes and contribute to both digestion and lubrication of the mouth.
-60-70%
-submandibular duct to lingual frenulum
features of sublingual glands
function: They produce thick, mucus-rich saliva, which helps to keep the mouth moist and assists in the initial stages of digestion.
-5%
-multiple ducts beneath & lateral to the tongue
parts of the teeth
-crown
-root
-dentin core
-deciduous
-permanent
what is the enamel a part of?
crown
parts of the root
-dental alveoli
-periodontal ligament
-cementum
-root canal
what is the pulp cavity a part of and what is the function?
-dentin core
-nourishes tooth
what are the deciduous teeth, how many teeth are in this category, and age of teeth?
-baby teeth
-lost
-20 teeth
-6 and 30 months
how many permanent teeth are there?
32 teeth
4 types of permanent teeth
-incisors
-canines
-premolars
-molars
what are the incisors?
front teeth and are designed for cutting and slicing food
what are the canines?
pointed teeth located on either side of the incisors, puncturing/tearing food
what are the premolars?
larger and have a flat biting surface with one or more cusps.
what are the molars?
largest and strongest teeth in the mouth, designed for grinding and crushing
refers to the cheek side of a tooth or the oral cavity
buccal
refers to the tongue side of a tooth or the oral cavity
lingual
chewing surface of a tooth; It is the top surface of the tooth that comes into contact with the opposing tooth when biting and chewing.
occlusal surface
describe a location or direction that is closer to the midline of the dental arch or closer to the front of the mouth
mesial
describes a location or direction that is farther away from the midline of the dental arch or closer to the back of the mouth
distal
parts of the pharynx
-oropharynx
-laryngopharynx
what is the vagus nerve, also known as the cranial nerve X (CN X) responsible for?
the vagus nerve has a pharyngeal branch in which muscles are innervated - process by which nerves supply signals to muscles, allowing them to contract and perform various functions. (ex: swallowing)
what is the glossopharyngeal nerve (cranial nerve IX) responsible for?
responsible for providing sensory innervation to the back of the throat, including the tonsils, the soft palate, and the back of the tongue.
3 phases of swallowing
-voluntary phase
-pharyngeal phase
-esophageal phase
what happens in the voluntary phase?
pushing food to hard palate
what happens in the pharyngeal phase?
-contact in oropharynx
-“gag reflex”
-larynx raises (epiglottis covers)
what happens in the esophageal phase?
-involuntary
-peristalsis
2 planes used to describe anatomical planes
-median plane (vertical plane)
-transumbilical plane (horizontal plane)
4 quadrants of the abdomen
-left upper
-left lower
-right upper
-right lower
features of the peritoneal cavity
-potential space
-visceral peritoneum
-parietal peritoneum
which organs are covered and not equally covered?
-intraperitoneal - completely
-retroperitoneal - only anterior surface of organ covered