39. Digestive System

Fat digestion yields fatty acids and glycerol. Protein digestion yields amino acids. Both digestive processes a. occur inside cells in most animals. b. add a water molecule to break bonds. c. require a low pH resulting from HCl production. d. consume ATP.

There are several key concepts introduced in this chapter: Structure correlates with function; an animal's body has a hierarchy of organization with emergent properties at each level; and complex bodies have structural adaptations that increase surface area for exchange. Label the tissue layers shown in this section of the small intestine, and describe how this diagram illustrates these three concepts.. a. Microvilli b. Mucosa c. Muscularis d. Sub-serous layer e. Serosa

Calculate and compare the caloric content of skim milk and whole milk. Per serving, skim milk contains 12 g carbohydrates, 8 g protein, and no fat; whole milk contains 12 g carbohydrates, 8 g protein, and 8 g fat.

The mammalian trachea and esophagus both connect to the a. pharynx. b. stomach. c. large intestine. d. rectum.

Evaluate the following statements regarding digestion; select True or False for each statement. T/F Salivary amylase completes the digestion of starch into monosaccharides. T/F Pepsin digests proteins in the stomach. T/F Trypsin digests disaccharides into monosaccharides. T/F Pancreatic lipase performs the majority of chemical digestion of lipids.

Which of the following organs is incorrectly paired with its function? a. stomach—protein digestion b. large intestine—bile production c. small intestine—nutrient absorption d. pancreas—enzyme production

After finding a gene that causes a disease, researchers often introduce the defective allele into mice to create an animal model of the disease. Why are these models valuable? a. They allow the testing of potential drug therapies without endangering human patients. b. They allow the sequencing of the mutant allele. c. They allow the production of large quantities of the defective gene product, usually a protein. d. They allow the study of how the gene was transmitted from parents to offspring.

Cellulose is fermented in which of the following structures in rabbits? a. small intestine b. cecum c. abomasum d. rumen

In which digestive system organ does nearly all nutrient absorption occur? (A) stomach (B) small intestine (C) large intestine (D) pancreas

The human genome size is 3 billion base pairs, and the size of the baker's yeast genome, a single-celled organism, is 12 million base pairs. Therefore, the predicted genome size for another single-celled organism, an amoeba, a. is about the size of the human genome b. is about the size of the yeast genome c. is somewhere between the sizes of the yeast and human genomes d. cannot be predicted with any certainty

Explain the role in nutrition of each of the following structures: bird crop, cow rumen, and elephant cecum.

If you put the following events in the order they occur in the human digestive system, the third event in the series would be a. Cells in gastric pits secrete protons. b. Pepsin activates pepsinogen. c. HCl activates pepsinogen. d. Partially digested food enters the small intestine.

After surgical removal of the gallbladder, a person might need to limit his or her dietary intake of a. starch. b. protein. c. sugar. d. fat.

Why is oral rehydration therapy with a solution of sodium chloride and glucose an effective treatment for dehydration? a. The sodium and glucose decrease urine output. b. The sodium and glucose facilitate water absorption by the small intestine. c. The sodium and glucose help kill intestinal bacteria. d. The sodium and glucose make the person thirsty.

Why is it important that the small intestine has a much greater surface area than the stomach or esophagus?

Use the Nutrition Facts label to the right to answer these questions: Each gram of fat supplies 9 Calories. Based on the grams of saturated fat and its % Daily Value, calculate the upper limit of saturated fat (in grams and Calories) that an individual on a 2,000-Calorie/day diet should consume.

Use the Nutrition Facts label to the right to answer these questions: Is this product a good source of vitamin D and calcium? Explain.

Use the Nutrition Facts label to the right to answer these questions: What percentage of the recommended daily value of fat is found in a 1-cup serving?

Among vertebrates, the large intestine exists only in lineages that are primarily terrestrial (amphibians, reptiles, and mammals). Propose a hypothesis to explain this observation.

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Like cichlids, minnows use their pharyngeal jaws to process food. Suggest some possible structural differences between the teeth on the pharyngeal jaws of carnivorous and herbivorous minnows.

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Which of the following is true of the digestive tracts of minnows? a. They are incomplete but have both a mouth and an anus. b. They are complete, facilitating compartmentalization of digestion in different organs. c. They are incomplete, with no accessory organs. d. They are complete and include a large gastrovascular cavity.

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Researchers compared the relative gut length—the length of the digestive tract divided by body length—in four species of herbivorous minnows and four species of carnivorous minnows. The results are shown in the graph provided here. Based on these data, what conclusion can you draw about the relationship between diet and gut length?

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Suggest a function of the difference in relative gut lengths of herbivorous and carnivorous minnows.

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Which minnows, herbivorous or carnivorous, should exhibit higher cellulase activity in the gut? Explain.

Minnows are mainly carnivorous, eating insects and other small animals. However, herbivory has evolved independently in minnows several times. What changes in digestive structure and function are associated with the evolution of herbivory? Why did the researchers compare relative gut length instead of absolute gut length?