23B Homework

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

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

Which of the following is NOT a characteristic of the stomach? The mucosa is organized into large, longitudinal folds called rugae. The stomach produces a double-layered coat of alkaline mucus. The muscularis externa has three layers of smooth muscle. The stomach releases enzymes that digest carbohydrates.

The stomach releases enzymes that digest carbohydrates.

Which of these structures is found in the stomach but nowhere else in the alimentary canal?

an oblique muscle layer 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 of the following are types of papillae on the tongue that contain taste buds?

fungiform and vallate

What is the condition called where a proximal portion of the stomach pushes through an opening in the diaphragm, allowing stomach acid to pass into the esophagus?

hiatal hernia

Which layer of the stomach contains the gastric pits that secrete mucus, acid, and digestive enzymes?

mucosa 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 muscle forms the labia of the mouth and controls most lip movement, including puckering?

orbicularis oris The orbicularis oris muscle is positioned surrounding the mouth and within the labia. It acts to control the movement of the lips.

Some antacid drugs block histamine receptors, resulting in reduction of the production and excretion of stomach acid. These drugs have the biggest effect on which of the following?

parietal cells

What event triggers the opening of the gastroesophageal sphincter?

peristalsis in the esophagus As the peristaltic wave triggered by deglutition reaches the stomach, the gastroesophageal sphincter relaxes and allows food into the stomach.

label the oral cavity and pharynx

pg. 876

label the salivary glands

pg. 878

Which area of the stomach directly adjoins the small intestine?

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

Gastric juice does not typically cause a burning sensation within the stomach. But reflux of gastric juice into the esophagus can cause a burning sensation. One reason for the burning sensation caused by the gastric reflux is that the esophagus ______.

secretes mucus that is not identical to stomach mucus The function of the mucus-producing esophageal glands is to lubricate the food bolus as it travels toward the stomach.

Which of the following is not a common risk factor for acid reflux disease?

sitting upright after a meal

The uvula is an extension of the __________.

soft palate The uvula extends out from and past the soft palate area of the palatopharyngeal arch.

Another term for swallowing is deglutition.

true