Consuming 30 g of which nutrient would provide the highest number of kcalories?

Correct Answer: B

Rationale: The correct answer is B, 'Fat.' Fat provides 9 kcalories per gram, which is more than carbohydrates and proteins that provide 4 kcalories per gram each. Therefore, consuming 30 g of fat would yield a higher number of kcalories compared to the same amount of carbohydrates or proteins. Micronutrients do not significantly contribute to kcalories, making them an incorrect choice in this scenario.

Correct Answer: B

Rationale: The correct answer is B: Essential fatty acids are not manufactured by the body. These fatty acids must be obtained through the diet because the body cannot synthesize them. Choice A is incorrect because essential fatty acids can come from both animal and plant sources, not just from an animal source. Choice C is the correct characteristic of essential fatty acids. Choice D is incorrect because essential fatty acids are not produced by the body.

Correct Answer: C

Rationale: The primary function of protein in the diet is to build and repair tissues. Proteins are essential for the growth, maintenance, and repair of body tissues like muscles, skin, and organs. While proteins can be a source of energy, their primary role is not to supply energy, making choice A incorrect. Choice B is also incorrect as proteins do not synthesize vitamins; rather, they are essential nutrients themselves. Choice D is inaccurate because glycogen is a form of stored glucose in the body, not a function of protein.

Correct Answer: B

Rationale: Lignin is the correct answer because it is a type of fiber that is not a carbohydrate and provides structure to plant cell walls. Gums (choice A), pectin (choice C), and cellulose (choice D) are all types of dietary fiber that are carbohydrates. Gums are a type of soluble fiber, pectin is found in fruits and is a soluble fiber, and cellulose is a type of insoluble fiber found in plant cell walls.

Correct Answer: B

Rationale: The correct answer is B: Supply energy. The primary function of macronutrients such as carbohydrates, fats, and proteins is to supply energy for various bodily functions. Choices A, C, and D are incorrect because while regulating metabolic processes, maintaining homeostasis, and controlling cellular activity are essential functions in the body, they are not the primary roles of macronutrients. Macronutrients mainly serve as a source of energy to support daily activities and bodily functions.