Mastering A&P #7

Which of these structures is found in the stomach but nowhere else in the alimentary canal? a. an oblique muscle layer b. a lining of columnar epithelium c. mucus-forming cells d. a circular muscle layer

a All areas of the alimentary canal have a circular and a longitudinal layer of muscle. The stomach has an additional oblique layer of muscle for "wringing" itself while processing food.

Which layer of the alimentary canal is responsible for segmentation and peristalsis? a. muscularis externa b. serosa c. submucosa d. mucosa

a Contractions of the circular and longitudinal layers of the muscularis externa produce the effects of peristalsis and segmentation. In the stomach, an additional muscle layer adds a twisting action.

Which of the following is NOT a means of mechanically breaking down food? a. peristalsis b. mastication c. segmentation d. churning

a Peristalsis is a physical process used for propulsion, or movement, through the GI tract.

Which of the following functions is NOT correctly matched with its description? a. propulsion: physical breakdown of ingested food in the GI tract b. mechanical breakdown: churning movements in the GI tracts c. ingestion: intake of food nutrients d. absorption: intake of chemically processed nutrients

a Propulsion is the movement of ingested food through the GI tract.

Where does the process of segmentation occur? a. small intestine b. stomach c. anus d. esophagus

a Several areas of the digestive tract are capable of peristalsis, which propels food onward, but only the small intestine undergoes segmentation, whose purpose is mixing food with enzymes and bringing it close to intestinal walls.

Which layer of the alimentary canal is constructed from either stratified squamous or simple columnar epithelium? a. mucosa b. serosa c. muscularis externa d. submucosa

a The mucosa's inner lining is composed of columnar epithelium for most of the alimentary canal. Stratified squamous is used in the esophagus, oral cavity, and anus.

Which area of the stomach adjoins the small intestine? a. pylorus b. cardia c. body d. fundus

a The pylorus is the lowest part of the stomach. It attaches to and empties food into the small intestine via the pyloric sphincter.

Which of the following inhibits salivation? a. being stressed or frightened b. ingestion of spicy foods c. the sight or smell of food d. relaxing after a meal

a The sympathetic division of the autonomic nervous system is associated with fight-or-flight responses. Stimulation of the salivary glands by the SNS tends to inhibit flow, as when you are scared or nervous and your mouth "goes dry."

How would you classify chewing food? a. mechanical breakdown b. digestion c. propulsion d. ingestion

a. mechanical breakdown Chewing breaks apart and grinds food and mixes it with saliva.

label the uvula hard palate tongue esophagus oropharynx epiglottis oral cavity trachea

art labeling question

label the following on the stomach cardia body rugae lesser curvature pyloric antrum pyloric sphincter fundus greater curvature

artistic label

The outermost tissue layer of the alimentary canal is the __________. a. submucosa b. serosa c. muscularis d. mucosa

b

Which digestive process does NOT occur in the mouth? a. digestion b. segmentation c. ingestion d. mechanical breakdown

b Segmentation is the back-and-forth mixing movement of food in the small intestine. The process of chewing and mixing food with saliva in the mouth is known as mastication.

Which of the following does NOT describe a basic regulator of digestive control? a. Digestive effectors are smooth muscle and glands. b. conscious neural control c. pH, stretch, and osmolarity are some of the inputs that can initiate digestive responses. d. Short reflexes act locally in the GI tract.

b. Neural control over the digestive system is through the autonomic nervous system, which does not function under conscious control mechanisms.

Unitary smooth muscle is found in all hollow organs except for the heart. What structure do both heart muscle and unitary smooth muscle share that allows them to contract as a functional group? a. T tubules b. epimysium c. gap junctions d. caveolae

c

Which of the following processes occurs in the stomach? a. deglutition b. absorption c. mechanical digestion d. defecation

c Mechanical digestion occurs in the stomach by churning.

Which layer of the stomach contains the gastric pits that secrete mucous, acid, and digestive enzymes? a. serosa b. muscularis externa c. mucosa d. submucosa

c The mucosa of the stomach contains the epithelial lining and the gastric pits, which extend down into the mucosa but do not penetrate the submucosa.

What role of the stomach is essential to life? a. production of hydrochloric acid b. production of VIP c. production of intrinsic factor d. production of chyme

c Without the production of intrinsic factor, the body would not be able to absorb vitamin B12 in the small intestine. This is the only factor that would cause problems with living.

Which of the following is NOT a function of saliva? a. Saliva moistens food and helps compact it into a bolus. b. Saliva cleanses the mouth. c. Saliva dissolves food chemicals so that they can be tasted. d. Saliva contains enzymes that begin the chemical breakdown of proteins.

d Saliva contains components with functions ranging from starch breakdown to fighting bacterial infection, but it does not contain any enzymes that digest protein.

How many total permanent teeth should an adult have, assuming none have been lost or removed? a. 8 b. 16 c. 20 d. 32

d There are two incisors (2I), one canine (1C), two premolars (2PM) and three molars (3M) for a total of 8 on each side of each jaw. Multiply by 4 for a total of 32 adult teeth.