Which of the following statements about obesity in older adults is true?

Correct Answer: B

Rationale: The correct answer is B because obesity can indeed contribute to complications like osteoarthritis due to increased pressure on the joints. This is supported by research showing a link between obesity and joint issues. Choice A is incorrect as obesity can have various causes beyond excessive eating. Choice C is incorrect as metabolism can vary among older adults, and obesity remains a concern regardless. Choice D is incorrect as obesity tends to be a persistent issue that requires management rather than resolving with age.

Correct Answer: B

Rationale: The correct answer is B: small intestine. The majority of chemical digestion occurs in the small intestine, specifically in the duodenum, where enzymes from the pancreas and bile from the liver break down food into nutrients. Stomach primarily performs mechanical digestion and initial protein breakdown. Mouth initiates mechanical digestion through chewing and begins carbohydrate digestion. Large intestine mainly absorbs water and electrolytes. Therefore, small intestine is the site of most chemical digestion due to its specialized enzymes and processes.

Correct Answer: C

Rationale: The main role of the stomach is the digestion of proteins. Step 1: Stomach secretes gastric juices containing pepsin and hydrochloric acid. Step 2: Proteins are broken down into peptides and amino acids. Step 3: These smaller molecules are then further digested and absorbed in the small intestine. Absorption of nutrients (A) primarily occurs in the small intestine, not the stomach. Bile is produced in the liver and stored in the gallbladder, not secreted by the stomach (B). The transport of food (D) occurs through the esophagus and into the stomach, not the main role of the stomach itself.

Correct Answer: C

Rationale: The correct answer is C: Secreting digestive enzymes. The pancreas secretes digestive enzymes such as amylase, lipase, and proteases to break down carbohydrates, fats, and proteins in the small intestine. This aids in digestion and absorption of nutrients. Producing insulin (Choice A) is a function of the pancreas but is primarily related to regulating blood sugar levels, not digestion. Producing bile (Choice B) is a function of the liver, not the pancreas. Absorbing nutrients (Choice D) is a function of the small intestine, not the pancreas. Therefore, the correct answer is C based on the role of the pancreas in digestion and enzyme secretion.

Correct Answer: D

Rationale: The correct answer is D, bile salts. The jejunum is primarily responsible for the absorption of nutrients like glucose, amino acids, and fatty acids. Bile salts are mainly absorbed in the ileum, the part of the small intestine that follows the jejunum. Bile salts aid in the digestion and absorption of fats, but they are not absorbed in the jejunum. Therefore, the jejunum is not the main site for absorption of bile salts. This makes option D the correct answer.