Medication for treating high blood cholesterol levels should not be used for most people unless:

Correct Answer: D

Rationale: The correct answer is choice D because medication for high cholesterol is typically not considered unless Therapeutic Lifestyle Changes (TLC), which include diet and exercise, have not proven effective after a three-month period. This approach ensures that lifestyle modifications are given a fair chance to lower cholesterol levels before resorting to medication. Choice A is incorrect because the number of risk factors for coronary heart disease does not dictate when to begin medication; it is about the effectiveness of lifestyle changes. Choice B is incorrect as the duration of coronary heart disease symptoms does not determine when to start medication; the focus is on the response to TLC. Choice C is incorrect because the coverage of prescription drugs by the patient's insurance does not influence the medical decision to use medication for high cholesterol; it is based on medical necessity and effectiveness of prior interventions.

Correct Answer: B

Rationale: Malnutrition is a common comorbidity in patients with Chronic Kidney Disease (CKD). This is mainly due to factors such as dietary restrictions, poor appetite, and the body's increased nutritional needs as it struggles to deal with the disease. Liver disease (Choice A) is not typically associated directly with CKD, although both conditions may coexist in some patients. Acute renal failure (Choice C) is not a comorbidity but a severe and potentially lethal progression of CKD. Difficulty breathing (Choice D) is not a comorbidity but can be a symptom of severe kidney disease or other underlying conditions. However, malnutrition is more commonly observed in CKD patients compared to difficulty breathing.

Correct Answer: B

Rationale: The correct answer is B. The classification of the 20 common amino acids is not based on the properties of their side chains, but rather on the structure of their amino and carboxyl groups. These groups are consistent among all amino acids, while the side chains, also known as R groups, are what vary and give each amino acid its unique properties. Choice A is correct because proteins are indeed composed of amino acids. Choice C is incorrect because while the side chains of amino acids can vary, the general structure of an amino acid - a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and a side chain - is consistent. Choice D is correct because amino acids do polymerize to form long chains called polypeptides, which can then fold into complex shapes to form proteins.

Correct Answer: A

Rationale: The first statement is correct as bacterial plaque can indeed metabolize sucrose, lactose, and fructose. However, the second statement is inaccurate. Fructose, despite being found naturally in honey and known also as levulose, is not less cariogenic than either sucrose or lactose. This means that its consumption does not result in fewer cavities or tooth decay. Therefore, the correct answer is that bacterial plaque can metabolize these sugars, but fructose is not less cariogenic. Choices B, C, and D are incorrect because they either wrongly assert that bacterial plaque cannot metabolize these sugars or wrongly claim that fructose is less cariogenic.

Correct Answer: D

Rationale: Prevident is indicated for all the situations listed in the choices. It is recommended for patients with a high risk of caries to reduce the risk of tooth decay. It is also used in dental procedures like crown and bridge work to strengthen enamel and prevent cavities. Furthermore, it is utilized for orthodontic decalcification to aid in remineralizing the tooth structure and prevent further damage. Therefore, the correct answer is 'All of the above.' While choices A, B, and C are individually correct, selecting 'All of the above' is the most appropriate as it encompasses all the possible indications for Prevident.