How many kilocalories (kcal) are provided by 35 g of fat?

Correct Answer: C

Rationale: Fat provides 9 kcal per gram, so 35 grams of fat provides 315 kcal. Therefore, the correct answer is C. Choice A (140) is incorrect because it doesn't consider the energy content of fat. Choice B (245) is incorrect as it miscalculates the kilocalories provided by 35g of fat. Choice D (360) is incorrect because it overestimates the kilocalories provided by 35g of fat.

Correct Answer: C

Rationale: The correct answer is C. Saturated fatty acids have no double bonds between carbon atoms, while unsaturated fatty acids have one or more double bonds. Therefore, the number of double bonds is the chemical feature that distinguishes a saturated fatty acid from an unsaturated fatty acid. Choices A, B, and D are incorrect because the distinguishing factor between saturated and unsaturated fatty acids lies in the presence or absence of double bonds, not in the arrangement of carbon atoms, number of oxygen molecules, or food source.

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.