What role do fats play in the human body?

Correct Answer: D

Rationale: Fats play various essential roles in the human body, one of which is aiding in the digestion of food. While fats do provide a concentrated source of energy, the primary source is carbohydrates. Proteins are the building blocks of enzymes and hormones, not fats. Essential fatty acids found in fats are vital for brain function and development, but this is not the primary role of fats in the body.

Correct Answer: A

Rationale: Monitoring for signs of infection is crucial in managing a central venous catheter to prevent complications. This involves observing for redness, swelling, warmth, or drainage at the catheter site, as these can indicate an infection. Restricting physical activity unnecessarily (choice B) can hinder the child's recovery and quality of life. Administering routine antibiotics (choice C) without a confirmed infection can lead to antibiotic resistance and unnecessary side effects. Increasing fluid intake only (choice D) is not the primary intervention for managing a central venous catheter.

Correct Answer: C

Rationale: Kilojoules are the standard units of energy used by most scientists and nutritionists worldwide. Newtons are units of force, liters are units of volume, and kilocalories are more commonly used in the United States but not as widely adopted internationally for energy measurements. Therefore, the correct answer is 'kilojoules.'

Correct Answer: D

Rationale: The correct answer is D: 13. There are 13 essential vitamins required in the diet of human beings, including vitamins A, C, D, E, K, and the B vitamins. Choice A (5), Choice B (8), and Choice C (10) are incorrect because they do not represent the total number of essential vitamins needed by human beings.

Correct Answer: B

Rationale: The correct answer is B: 'To promote overall health and reduce the risk of chronic diseases.' Dietary guidelines aim to improve public health by providing recommendations on dietary patterns and nutrient intake. While ensuring food safety and sanitation (choice A) is important, it is not the primary purpose of dietary guidelines. Preventing foodborne illnesses (choice C) is more related to food safety practices rather than dietary guidelines. Recommendations for physical activity (choice D) are important for overall health but are separate from dietary guidelines, which primarily focus on nutrition.

Correct Answer: C

Rationale: One major weakness of laboratory-based studies is that results from animal testing cannot always be applied to human beings. This limitation arises due to the inherent biological differences between animals and humans, making the generalization of findings challenging. While costs may be a concern in some cases, they do not represent a universal weakness of laboratory-based studies. Findings in such studies can be replicated to ensure validity, and experimental variables can be effectively controlled in a laboratory setting. Choice C is the correct answer because the translatability of results from animal studies to humans is a significant challenge in laboratory-based research, impacting the direct application of findings to human health and well-being.

Correct Answer: D

Rationale: The correct answer is D. Nutrient recommendations are designed to meet the needs of most healthy people, providing guidelines for a balanced diet. Choice A is incorrect because while nutrition plays a crucial role in health, it is not the only factor influencing it. Choice B is incorrect as nutrient needs vary based on factors like age, gender, activity level, and health status. Choice C is incorrect because all nutrients are essential for different bodily functions, and none can be deemed universally more important than others.

Correct Answer: B

Rationale: The correct answer is B, Theophylline. Theophylline is commonly used for long-term control of asthma by relaxing the muscles around the airways to keep them open, making breathing easier. Albuterol (choice A) is a short-acting bronchodilator for quick relief of asthma symptoms, not for long-term control. Ipratropium (choice C) is another short-acting bronchodilator that helps open the airways but is not typically used for long-term control. Prednisone (choice D) is a corticosteroid usually used for short periods to control asthma exacerbations or flare-ups, not as a long-term control medication.

Correct Answer: D

Rationale: The correct answer is D. Controls in an experiment ensure that the subjects are similar in all respects except for the treatment being tested. This allows for a fair comparison between the treatment group and the control group. Choice A is incorrect because the size of the groups is not the primary benefit of using controls. Choice B is incorrect as blinding, not controls, refers to subjects not knowing about the experiment. Choice C is incorrect as it pertains more to randomization than the use of controls.