Which consumption pattern of fermentable carbohydrate is considered most cariogenic?
- A. A single exposure to a large quantity
- B. A single exposure to a small quantity
- C. Multiple exposures of small quantities
- D. Multiple exposures followed by chewing sugarless gum
Correct Answer: C
Rationale: Multiple exposures of small quantities are considered most cariogenic. The total amount of dietary fermentable carbohydrate seems to matter less than the form and frequency in which it is consumed. Having multiple exposures of even small quantities of fermentable carbohydrate throughout the day promotes a highly cariogenic environment in the mouth. Choices A and B, involving single exposures, are less cariogenic as they do not sustain the fermentation process over time. Choice D suggests a beneficial practice by chewing sugarless gum after exposures, which can reduce the risk, making it less cariogenic compared to multiple exposures of small quantities.
You may also like to solve these questions
Complex carbohydrates contain more than 10 monosaccharides. Complex carbohydrates are also called disaccharides.
- A. Both statements are true.
- B. Both statements are false.
- C. The first statement is true; the second is false.
- D. The first statement is false; the second is true.
Correct Answer: C
Rationale: The first statement is true; the second is false. Complex carbohydrates are also called polysaccharides and contain more than 10 monosaccharides. Choice A is incorrect because the second statement is false. Choice B is incorrect because the first statement is true. Choice D is incorrect because the second statement is false.
What physiologic role does calcium play in the body?
- A. Blood clotting, transmission of nerve impulses, muscle contraction and relaxation
- B. Calcium homeostasis, structural integrity of heart muscle
- C. No known metabolic function, caries-preventing properties
- D. ATP energy release; metabolism of fats, carbohydrates, proteins; regulates acid-base balance.
Correct Answer: A
Rationale: The correct answer is A: 'Blood clotting, transmission of nerve impulses, muscle contraction and relaxation.' Calcium plays a crucial role in various physiological functions such as blood clotting, transmission of nerve impulses, muscle contraction and relaxation, membrane permeability, and activation of certain enzymes. Choice B is incorrect because while calcium is involved in calcium homeostasis, it is not the only role it plays in the body. Choice C is incorrect as calcium indeed has several known metabolic functions, and it is not solely for preventing caries. Choice D is also incorrect as the functions mentioned are primarily carried out by other nutrients and not specifically by calcium.
Which nutrient deficiency produces microcytic anemia, fatigue, faulty digestion, blue sclerae, pale conjunctivae, and tachycardia?
- A. Zinc
- B. Iron
- C. Sodium
- D. Potassium
Correct Answer: B
Rationale: A deficiency in iron can lead to various symptoms, such as microcytic anemia, fatigue, faulty digestion, blue sclerae, pale conjunctivae, and tachycardia. Iron-deficiency anemia may be caused by inadequate dietary intake; accelerated demand or losses; and inadequate absorption secondary to diarrhea, decreased acid secretions, or antacid therapy. Iron deficiency is frequently the result of postnatal feeding practices and has a serious impact on growth and mental and psychomotor development in infants and children. Choices A, C, and D are incorrect as zinc deficiency typically presents with symptoms like impaired wound healing, taste abnormalities, and hair loss; sodium deficiency can lead to symptoms such as muscle cramps, dizziness, and confusion; and potassium deficiency may cause muscle weakness, fatigue, and abnormal heart rhythms.
Each statement is true of vitamin K, except one. Which is the exception?
- A. Vitamin K is produced in the gut.
- B. Vitamin K functions as a catalyst for the synthesis of blood-clotting factors.
- C. Vitamin K maintains prothrombin levels.
- D. Vitamin K absorption increases with high levels of vitamin E supplementation.
Correct Answer: D
Rationale: The correct answer is D. Vitamin K absorption decreases with high levels of vitamin E supplementation because in larger amounts, vitamin E acts as an anticoagulant. Vitamin K is not produced in the gut but can be obtained from food sources or supplements. Vitamin K is essential for the synthesis of blood-clotting factors and is crucial in maintaining prothrombin levels, which is vital for proper blood clotting. The incorrect choice, D, is misleading as high levels of vitamin E supplementation hinder vitamin K absorption due to its anticoagulant properties. Dental hygienists should be aware of the importance of vitamin K in blood clotting, especially when treating patients who are on anticoagulant medications for conditions like stroke prevention.
Inadequate intake of vitamin A occurs in lower socioeconomic groups due to a lack of resources to purchase and consume vegetables and fruits.
- A. Both the statement and the reason are correct and related.
- B. Both the statement and the reason are correct but are not related.
- C. The statement is correct, but the reason is not correct.
- D. The statement is not correct, but the reason is correct.
Correct Answer: A
Rationale: Both the statement and the reason are correct and related. Inadequate intake of vitamin A in lower socioeconomic groups is due to a lack of resources to purchase and consume vegetables and fruits. This is supported by the fact that the average intake in the United States meets the Recommended Dietary Allowance (RDA) for vitamin A intake, except in lower socioeconomic groups. These individuals often lack the financial means to buy, prepare, and eat a variety of fruits and vegetables, leading to deficiencies. It's important to note that because vitamin A can be stored in the liver, most adults have sufficient quantities to maintain health. Choices B, C, and D are incorrect because the statement and reason are both accurate and logically connected, as the lack of resources directly impacts the ability to obtain necessary sources of vitamin A.