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

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 genomeb. is about the size of the yeast genomec. is somewhere between the sizes of the yeast and human genomesd. cannot be predicted with any certainty

The energy content of fatsa. is released by bile salts.b. is, per gram, twice that of carbohydrates or proteins.c. cannot be dissolved in water and so cannot be absorbed.d. is usually healthier than the energy content of carbohydrates.

Which of the following vitamins is mismatched with the disease that results from its underconsumption?a. vitamin B6—beriberib. vitamin C—scurvyc. vitamin A—vision lossd. vitamin D—rickets

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

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

Which of the following statements is false?a. A healthy human has enough stored fat to supply calories for several weeks.b. An increase in leptin levels leads to an increase in appetite and weight gain.c. The interconversion of glucose and glycogen takes place in the liver.d. After glycogen stores are filled, excessive calories are stored as fat, regardless of their original food source

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 necessary for healthy vegetarians to combine different plant foods or eat some eggs or milk products?a. to make sure they obtain sufficient caloriesb. to provide sufficient vitaminsc. to make sure they ingest all essential fatty acidsd. to provide all essential amino acids for protein synthesis