Structures of the digestive system

tigrebright's version from 2015-10-19 13:16

Section 1

Question Answer
gastrointestinal tractthe primary part of the digestive tract
upper GI tractmouth, pharynx, esophagus, stomach-transports food from the entry into the body until digestion begins in the stomach
lower GI tractsmall and large intestine, rectum and anus-here digestion is completed, and waste material is prepared for expulsion from the body
accessory organs of the digestive systemliver, gallbladder and pancreas
oral cavityaka mouth; lips, hard and soft palate, salivary glands, tongue, teeth and periodontium
labialips; surround the opening to the oral cavity
palatethe roof of the mouth
hard palateanterior portion; covered specialized mucous membrane
rugaeirregular ridges or folds in the mucous membrane of the hard palate
soft palatethe flexible posterior portion of the palate
uvulathird part of the palate; hangs from the free edge of the soft palate; moves upward with the soft palate during swallowing

Section 2

Question Answer
tonguevery strong, flexible and muscular
dorsumupper surface of the tongue;has a tough protective covering
papillaesmall bumps on the dorsum of the tongue containing taste buds
taste budssensory receptors for the sense of taste
sublinguinal surfacetissues that lie under the tongue and are covered with delicate highly vascular tissues
sublinguinalunder the tongue
highly vascularcontaining many blood vessels
lingual frenumband of tissue that connects the tongue to the floor of the mouth
periodontiumthe structures that surround, support, and are attached to the teeth;
gingivaaka masticatory mucosa or gums;

Section 3

Question Answer
dental archesthe bony structures of the oral cavity; they hold the teeth firmly in position to facilitate chewing and speaking
maxillary archaka upper jaw;
mandibular archaka lower jaw;
temporomandibular jointaka TMJ;
dentitionrefers to the natural teeth
incisors and caninesaka cuspids; used for biting and tearing
premolarsaka bicuspids and molars; used for chewing and grinding
primary dentitionaka deciduous dentition or 20 baby teeth;
permanent dentition32 permanent teeth
occlusionany contact between the chewing surfaces of the upper and lower teeth

Section 4

Question Answer
crownportion of the tooth that is visible in the mouth
enamelcovering of the tooth; the hardest substance in the body
rootshold teeth securely in the dental arch
cementumprotects the roots of the teeth
cervixaka the neck of the tooth; where the crown and root meet
dentinmakes up the bulk of the tooth
pulp cavityarea within the crown and roots of the tooth that is surrounded by the dentin to protect the delicate pulp of the tooth
root canalsspace in the roots of teeth that contains the pulp
pulpconsists of a rich supply of blood vessels and nerves that provide nutrients and innnervation to the tooth
salivaa colorless liquid that maintains the moisture in the mouth; helps maintain the health of the teeth, and begins the digestive process by lubricating food during chewing and swallowing
salivary glandssecrete saliva that is carried by the ducts into the mouth
parotid glandslocated on the face, slightly in front of each ear;ducts are located on the inside of the cheek near the upper molars
sublinguinal glandsglands and ducts are located on the floor of the mouth under the tongue
submandibular glandsglands and ducts are located on the floor of the mouth near the mandible

Section 5

Question Answer
pharynxthe common passageway for both respiration and digestion
deglutitionaka swallowing
epiglottislid-like sturcture that closes off the entrance to the trachea to prevent food and liquids from moving from the pharynx during swallowing
esophagusthe muscular tube through which ingested food passes from the pharynx to the stomach
lower esophageal sphincteraka cardiac sphincter; a muscular ring between the esophagus and stomach
regurgitatingto flow backward
stomacha sac-like organ composed of the fundus, body, and antrum
fundusupper, rounded part of the stomach
bodymain portion of the stomach
antrumlower part of the stomach
rugaefolds in the mucosa ling of the stomach;allow flexibility of the stomach increasing and decreasing in size;glands are located within the folds that produce gastric jiuces
gastric juicesaid in the beginning of food digestion;mucus produced by glands in the stomach create a protective coating on the lining of the stomach
phloric sphincterring-like muscle at the base of the stomach that controls the flow of partially digested food from the stomach to the duodenum of the small intestine
pylorusthe narrow passage that connects the stomach with the small intestine

Section 6

Question Answer
small intestineextends from the pyloric sphincter to the first part of the large intestine; it is 20 ft in length and consists of 3 sections; this is where food is digested and the nutrients are absorbed into the bloodstream
duodenumthe first portion of the small intestine
jejunumthe middle portion of the small intestine
ileumthe last and longest portion of the small intestine
large intestineextends from the end of the small intestine to the anus;wider but shorter that the small intestine; it is where waste products of digestion are processed in preparation for excretion through the anus
cecumthe pouch that lies on the right side of the abdomen
ileocecal sphincterthe ring-like muscle that controls the flow from the ileum of the small intestine into the cecum of the large intestine
vermiform appendixhangs from the lower portion of the cecum; consists of lymphoid tissue
vermiformrefers to worm-like shape
colonthe longest portion of the large intestine
ascending colonon the right side of the body;travels upward from the cecum to the undersurface of the liver
transverse colonpasses horizontally across the abdominal cavity from right to left toward the spleen
descending colontravels down the left side ot the abdominal cavity to the sigmoid colon
sigmoid colons-shaped structure that continues from the descending colon above and joints the rectum below
sigmoidcurved like the letter S
rectumwidest division of the large intestine; it makes up the last 4 inches of the large intestine and ends at the anus
anusthe lower opening of the digestive tract;leading to the outside of the body
internal and external anal sphincterthese control the flow of waste through the anus
anorectalrefers to the anus and rectum as a single unit

Section 7