Lab 7 Assignment
The muscularis externa contains __________ sheets of muscle throughout most of the alimentary canal wall. The fibers in these layers are arranged at __________ angles to each other.
2; right
the undigested food passes through the:
ascending, transverse, descending, and sigmoid portions of the colon into the rectum and anal canal
the single digestive function of the liver is to produce:
bile
list the four regions of the stomach
cardia, fundus, body, pyloric
the large intestine includes the:
cecum, appendix, colon, rectum, and anal canal
The muscular stomach is involved in ________________ and ________________ digestion, as well as food storage.
chemical; mechanical
once food is mixed with gastric juices in the stomach, it is called:
chyme
The muscularis mucosa has both ___________ and _________ layers of muscle in the muscularis externa.
circular and longitudinal
From largest to smallest, list the three modifications of the small intestine's inner wall that function to increase surface area
circular folds, villi, and microvilli
lamina propira
connective tissue layer containing blood and lymphatic vessels
simple columnar epithelium
densely populated with goblet cells
The function of the double-layered muscularis mucosa is to aid in _______ and ________ by moving the _________________ in the small intestine
digestion and absorption; mucosal vili
list, in order from the pylorus to the colon, the three regions of the small intestine
duodenum, jejunum, and ileum
the three regions of the small intestine are the:
duodenum, jejunum, and ileum
the partially ingested bolus of food is moved from the mouth to the ___________, and then to the _____________.
esophagus; stomach
feces are composed of:
indigestible food, bacteria, inorganic substances, and sloughed off epithelial cells
The muscularis externa layer of the stomach wall is unique in that it has three sheets of muscle, which are:
longitudinal, circular, and oblique
list the three sheets of muscle in the stomach's muscularis externa
longitudinal, circular, oblique
mucosal epithelial cells are ____________ active, thus the epithelium is replaced approximately every ________ days.
mitotically; three to six
three pairs of salivary glands function to:
moisten food in the mouth
the four main layers of the digestive tract wall from inside to outside are:
mucosa, submucosa, muscularis (externa), & serosa
absorption of nutrients occurs through the:
mucosal epithelium and into either capillaries or lacteal lymphatic vessels
Goblet cells secrete:
mucus
The network of neurons in between the two muscle layers of the muscularis externa is the ____________________.
myenteric plexus
Blood and lymph vessels as well as an intrinsic network of _____________ are located in the submucosa.
neurons
sphincters regulate the passage of food from:
one region of the digestive tract to the next, and finally, out of the body as feces
the main digestive enzyme- producing exocrine organ in the body is the
pancreas
The two types of movements produced by contractions of the muscularis externa are
peristalsis and segmentation
enteroendocrine cells of the mucosa:
produce hormones that are released into the blood via the capillaries of the lamina propria.
the stomach can expand greatly because of internal folds called:
rugae
The mucosa is subdivided into three layers. From the lumen (inward) outward they are:
simple columnar epithelium, lamina propria, and muscularis mucosa
the majority of chemical digestion and virtualy all-nutrient absorption occur in the
small intestine
There is a transition in the esophagus wall from striated to _____________ muscle, from the upper to lower portions.
smooth
muscularis mucosa
smooth muscle sheet
the anus is lined with __________________ epithelium
stratified squamous
the lining of the oral cavity and pharynx is a _____________________ epithelium mucosa.
stratified squamous
The mouth, with its _____________________ epithelium, is involved in both chemical and __________________ digestion.
stratified squamous; mechanical
The built-in network of nerve cells in the submucosa is the __________________________.
submucosal plexus
three bands of smooth muscle called _____________ cause the outer portion of the colon to be puckered into pockets called ______________.
taeniae coli; haustra
List two main divisions of the digestive system
the alimentary system (digestive tract) & accessory organs
the sphincters of the digestive tract, from the mouth to the anus, are:
upper esophageal sphincter, lower esophageal sphincter, pyloric sphincter, ileocecal sphincter, internal anal sphincter, and external anal sphincter
the large intestine absorbs:
water, salt, and vitamin K
