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