Which is NOT a characteristic or function of lipids?

Correct Answer: D

Rationale: Lipids are known for several functions including involvement in energy metabolism and storage (Choice A), providing insulation and protection (Choice B), and acting as hormones that regulate the body (Choice C). However, lipids are not hydrophilic (water-attracting), contrary to choice D. They are actually hydrophobic, meaning they repel water and do not mix well with it. This is a key property that differentiates them from many other biological molecules.

Correct Answer: B

Rationale: All the statements above are accurate about oral exposure to fermentable carbohydrates, except for option B. In fact, longer exposure to these carbohydrates decreases the opportunity for remineralization. This is because the process of demineralization, in which minerals are lost from the tooth enamel, is sped up by the presence of fermentable carbohydrates. The Stephan curve (option C) is a graph that demonstrates how the pH of dental plaque changes after a sugar rinse, usually dropping (becoming more acidic), which can lead to enamel decalcification. Option D is also accurate, as a pH of 5.5 or lower is the critical point at which enamel starts to decalcify.

Correct Answer: D

Rationale: MI Paste is contraindicated in children under six and in individuals with a milk casein allergy. The reason is that MI Paste contains casein phosphopeptide, which is derived from milk. Therefore, it may cause allergic reactions in those who are sensitive to milk proteins. Pregnant women (Choice C) are not contraindicated for using MI Paste unless they have a known allergy to milk casein. Hence, the correct answer is 'D: Both A and B'.

Correct Answer: C

Rationale: Adolescence is the most critical stage for building bone mass, which plays a significant role in preventing osteoporosis in later life. During adolescence, approximately 45% of adult bone mass is formed. Although bone mass can be built during infancy, early childhood, and young adulthood, it is not as significant as during adolescence, making choices A, B, and D incorrect. Therefore, focusing on adequate nutrition and physical activity during adolescence is vital for long-term bone health.

Correct Answer: A

Rationale: The primary goal of a dental hygienist when making dietary recommendations for a patient with a new dental prosthesis is to promote healing and repair. This can be achieved by ensuring the patient maintains an adequate and nutrient-dense diet. This is why option 'A' is the correct answer. Option 'B' is incorrect because while liquids are easier to consume with a new dental prosthesis, a diet consisting only of liquids for a week may not provide all necessary nutrients. Option 'C' is incorrect because while a variety of fibrous foods can contribute to a healthy diet, it's not specifically relevant to the healing and adjustment to a new dental prosthesis. Option 'D' is incorrect because eating as usual may not be feasible or comfortable for a patient with a new prosthesis, and it doesn't specifically focus on promoting healing and repair.