Digestive System Flashcards
The __________ system is the conduit
for delivery and removal of what is
necessary to support cells and tissues of
the body
cardiovascular
A ________ is a double sheet of peritoneal
membrane; the peritoneal membrane lines
the abdominal cavity. Mesenteries stabilize
the position of organs attached to the
abdominal wall and prevent tangling of
intestines during movement of the tract or
sudden changes in body position.
mesentery
What does the mesentery consist of
Mesothelium, areolar tissue, mesothelium
What are the major layers of the digestive tract
Mucosa, submucosa, muscularis Externa, serosa
Mucosa
epithelial lining and underlying connective tissue
Submucosa
connective tissue containing blood vessels and
glands
Muscularis externa
smooth muscle in two layers – inner circular
layer and outer longitudinal layer
Serosa/adventitia
the serosa is a peritoneal membrane covering;
it is not present in oral cavity, pharynx, esophagus and rectum – instead they have an adventitia
The ________ is especially constructed to
facilitate absorption of nutrients from the
lumen of the tract
mucosa
The _________ in the upper part of the tract
(oral cavity, pharynx and esophagus) is
stratified squamous where the rest of the
tract is simple columnar
epithelium
_________ and ________ increase
surface area for absorption
Circular folds, intestinal villi
__________ in the mucosa and
submucosa produce secretions that are
carried through ducts to epithelial surfaces.
Secretory glands
The ___________ has smooth muscle
within it that change the shape of the lumen
and move the circular folds and villi.
muscularis mucosa
What are the 2 secretory glands of the digestive tract?
Mucosal gland, submucosal gland
What are the 4 components of the mucosa
Epithelial layer, Villi, lamina propia, muscularis mucosae
Describe the movement of food through the digestive tract
1) Bolus of food arrives in the digestive system
2) Circular muscles contract behind bolus
3) Longitudinal muscles ahead of bolus contract
4) Contraction in circular muscle layer forces bolus forward.
\_\_\_\_\_\_\_\_ is the process of smooth muscle contraction by which materials are moved from one portion of the digestive tract to another. Longitudinally oriented smooth muscle contracts and shortens the segment of gut ahead of the food bolus, then circularly-oriented smooth muscle contracts to push it forward
Peristalsis
________ is the process of smooth muscle contraction by which materials are churned and fragmented, mixing the contents of the tract with secretions. These muscle contractions don’t happen in any set pattern so contents are not propelled in any particular direction
Segmentation
All movements of the gut are under the control of three primary mechanisms:
• Autonomic nervous system • Hormones produced by the digestive tract itself • Local factors such as changes in pH, mechanical distortion of the gut wall, or chemical signals released from the mucosa and/or specific nutrients
What are the major organs of the digestive tract?
Oral cavity(mouth), Pharynx, Esophagus, Stomach, Small/Large Intestine
What are the accessory organs of the digestive tract
Teeth, tongue, salivary glands, liver, gallbladder, pancreas
What is the function of the oral cavity for digestive purposes?
Mechanical processing with accessory organs (teeth and tongue), moistening, mixing with salivary secretions
What is the function of the pharynx for digestive purposes?
Muscular propulsion of materials into the esophagus
What is the function of the esophagus for digestive purposes?
transport of materials to the stomach
What is the function of the stomach for digestive purposes?
Chemical breakdown of materials by acid and enzymes; mechanical processing through muscular contractions
What is the function of the small intestine for digestive purposes?
Enzymatic digestion and absorption of water, organic substrates, vitamins, and ions
What is the function of the large intestine for digestive purposes?
Dehydration and compaction of indigestible materials in preparation for elimination
What are the functions of the digestive tract?
Ingestion, digestion, absorption.
What is the compact material created from digestion?
feces
The discharge of feces from the body is called what
defecation
What makes up the superior boundary of the oral cavity?
Hard and soft palate
What makes up the posterior boundary of the oral cavity?
uvula, palatine tonsil, root of the tongue, pair of lingual tonsils
What makes up the anterior and lateral boundary of the oral cavity?
Labia, cheeks
What makes up the inferior boundary of the oral cavity?
Floor of the mouth inferior to the tongue
______ is the matrix of the tooth, similar in construction to the matrix of bone
Dentin
The _____ of the tooth projects into the oral cavity from the surface of the gums
Crown
The _____ of each tooth sits in a bony cavity called an alveolus, or tooth socket
root