ch. 3

Which of the following is a function os sphincter muscles? a. control the passage of food through the GI tract b. control peristalsis c. grind large food particles d. secrete digestive juices into the GI tract

a. control the passage of food through the GI tract

What is mastication a. the act of chewing b. the act of swallowing c. the wave-like contraction of the intestines d. the wave-like contraction of the esophagus

a. the act of chewing

What is the function of bile? a. Enhances absorption of complex carbohydrates b. Emulsifies fats c. Initiates digestion of protein d. Protects the stomach and small intestine from the action of hydrochloric acid

b. Emulsifies fats

Which of the following products of digestion is NOT normally released directly into the bloodstream? a. Vitamin C b. Fats c. Minerals d. Carbohydrates

b. Fats

Which of the following is a description of chyme a. a semiliquid mass of partially digested food released by the stomach into the small intestine b. The mixture of pancreatic juices containing enzymes for digestion of the macronutrients c. A thick, viscous material synthesized by mucosal cells for protection against digestive juices d. The semisolid mass of undigested food that passes through the ileocecal valve

a. a semiliquid mass of partially digested food released by the stomach into the small intestine

Exchange of oxygen, nutrients, and waste materials takes place across the walls of small vessels called a. capillaries. b. venules. c. arterioles. d. ducts.

a. capillaries.

Which of the following is a feature of peristalsis? a. its occurs along the GI tract at a constant rate with food is present b. it consists of wavelike muscular contractions resulting from alternate tightening and relaxing of circular muscles and longitudinal muscles c. it involves parallel and circular muscles found in the walls of the intestines but not the stomach d. it remains quiet between meals with the GI tract is empty

b. it consists of wavelike muscular contractions resulting from alternate tightening and relaxing of circular muscles and longitudinal muscles

What type of enzymes are responsible for hydrolyzing the proteins in foods a. lipases b. proteases c. carboghydrases d. salivases

b. proteases

Among the GI tract organs, which has the strongest muscles a. large intestine b. stomach c. cardiac sphincter d. small intestine

b. stomach

What is the lumen of the GI tract a. the epiglottis b. the inner space c. the capillaries d. the mucosal surface

b. the inner space

Which of the following are found on the microvilli and function to break apart small nutrients into the final products of digestion? a. Hormones b. Micelles c. Enzymes d. Mucus

c. Enzymes

Which of the following would NOT be acted upon by pancreatic juice secreted into the intestinal tract? a. Carbohydrates b .Fats c. Fiber d. Proteins

c. Fiber

When nutrients are transported from intestinal epithelial cells to the vascular system, what organ is first to receive them? a. Lungs b. Heart c. Liver d. Kidneys

c. Liver

Which of the following body organs does not secrete digestive enzymes? a. Stomach b. Pancreas c. Liver d. Salivary glands

c. Liver

What is the primary site for absorption of nutrients? a. Crypt b. Villus c. Microvillus d. Macrovillus

c. Microvillus

Why is there little or no digestion of starch in the stomach a. Mucus inhibits starch breakdown b. Stomach enzymes are dysfunctional c. Salivary enzymes do not work in an acid environment d. Starch should not be eaten with protein

c. Salivary enzymes do not work in an acid environment

What part of the GI tract prevents a person from choking while swallowing a. upper esophageal sphincter b. mouth c. epiglottis d. pyloric sphincter

c. epiglottis

What is a bolus a. enzyme that hydrolyzes starch b. sphincter muscle separating the stomach from the small intestine c. portion of food swallowed at one time d. device used to analyze the contents of the stomach

c. portion of food swallowed at one time

A solution with a pH of 7 is how many times more alkaline than one with a pH of 6? a. 100 b. 1 c. 5 d. 10

d. 10

After the pancreatic juices have mixed with chyme in the small intestine, which of the following describes the pH of the resulting mixture? a. Moderately acidic b. Strongly alkaline c. Very acidic d. Approximately neutral

d. Approximately neutral

What is a function of hydrochloric acid in the stomach? a. Inhibits peristalsis b. Absorbs water c. Neutralizes the food mass d. Creates an optimum acidity

d. Creates an optimum acidity

Which of the following is generally NOT digested but does stimulate intestinal muscle contractions? a. Bile b. Starch c. Amylase d. Fiber

d. Fiber

The process by which food is broken down into absorbable components is called a. mastication b. absorption c. excretion d. digestion

d. digestion

In what organ does the digestion process begin a. jejunum-ileum b. stomach c. duodenum d. mouth

d. month

What is the function of mucus in the stomach a. emulsifies fats b. neutralizes stomach acid c. activates pepsinogen to pepsin d. protects stomach cells from gastric juices

d. protects stomach cells from gastric juices