Chapter 3 Questions - The Science of Nutrition

The region of brain tissue that is responsible for prompting us to seek food is the…

a. pituitary gland.

b. satiety center.

c. Hypothalamus.

d. Thalamus.

c. Hypothalamus.

In travelling through your GI tract, chyme would encounter…

a. the esophagus, then the stomach.

b. the duodenum, then the jejunum, and then the ileum.

c. he liver, then the gallbladder, and then the pancreas.

d. the jejunum, then the transverse colon, the ascending colon, and finally the anus.

b. the duodenum, then the jejunum, and then the ileum.

The parietal cells of the stomach secrete hydrochloric acid, which…

a. begins to denature proteins.

b. accomplishes protein digestion.

c. begins to digest carbohydrates.

d. is more acidic than battery acid.

a. begins to denature proteins.

Which of the following statements about chemical digestion is true?

a. Enzymes are chemical messenger molecules that are important in regulating many aspects of digestion.

b. Hormones are nearly always produced in the same organ whose activity they assist.

c. Most hormones and enzymes involved in digestion are nonspecific, acting on a wide variety of compounds.

d. Upon release into the GI tract, digestive enzymes typically facilitate hydrolysis reactions.

d. Upon release into the GI tract, digestive enzymes typically facilitate hydrolysis reactions.

Bile is a greenish fluid that

a. is produced by the gallbladder.

b. is stored by the pancreas.

c. is necessary for the absorption of vitamin B12.

d. emulsifies lipids.

d. emulsifies lipids.

The lining of the small intestine…

a. has muscular ridges called rugae that flatten to increase its absorptive capacity.

b. is studded with lymph nodes that absorb nutrients from the chyme.

c. has fingerlike projections called villi that contain capillaries and a lacteal that pick up absorbed nutrients.

d. has absorptive cells called enterocytes that line the microvilli.

c. has fingerlike projections called villi that contain capillaries and a lacteal that pick up absorbed nutrients.

A process in which nutrients are shuttled across enterocytes with the help of a carrier protein but no use of energy is…

a. passive diffusion.

b. facilitated diffusion.

c. active transport.

d. Endocytosis.

b. facilitated diffusion.

Which of the following processes moves food along the entire GI tract?

a. mass movement

b. Peristalsis

c. Haustration

d. Segmentation

b. Peristalsis

Gastroesophageal reflux disease is caused

a. by pooling of gastric juice in the lower esophagus.

b. when a hypersensitivity immune response triggers inflammation of the esophagus and stomach.

c. by ulceration of the lining of the stomach or duodenum.

d. by an inappropriate response of enteric nerves to stress

a. by pooling of gastric juice in the lower esophagus.

Colorectal cancer…

a. accounts for nearly one-fourth of all cancers of the gastrointestinal system.

b. is the most common cancer in both men and women.

c. has been linked to diets high in whole grains, fruits, vegetables, and other sources of dietary fiber.

d. can be detected with a screening test before it produces signs or symptoms

d. can be detected with a screening test before it produces signs or symptoms

True or false? Hunger is more physiological, and appetite is more psychological.

True

True or false? Vitamins and minerals are digested in the small intestine.

False

True or false? The pancreas secretes inactive enzymes, hormones, and bicarbonate.

True

True or false? The nerves in the walls of the GI tract are part of the central nervous system.

False

True or false? Acute diarrhea is typically protective.

True