The energy content of fats a. is released by bile salts. b. is, per gram, twice that of carbohydrates or proteins. c. cannot be dissolved in water and so cannot be absorbed. d. is usually healthier than the energy content of carbohydrates.

Verified step by step guidance

1. Identify the question: The problem is asking about the characteristics of the energy content of fats.
2. Analyze the options: Consider each statement in relation to what you know about fats, their digestion, and their energy content.
3. Recall the role of bile salts: Bile salts emulsify fats in the digestive system, but they do not release energy from fats.
4. Compare energy content: Remember that fats provide about 9 calories per gram, whereas carbohydrates and proteins provide about 4 calories per gram. This makes the energy content of fats more than twice that of carbohydrates or proteins.
5. Consider solubility and absorption: Fats are insoluble in water, but they can be absorbed with the help of bile salts and enzymes like lipases.

Key Concepts

Energy Content of Macromolecules

Fats, carbohydrates, and proteins are the three primary macromolecules that provide energy to the body. Fats contain approximately 9 calories per gram, while carbohydrates and proteins each provide about 4 calories per gram. This significant difference in energy content is crucial for understanding dietary choices and energy metabolism.

Absorption of Fats

Fats are hydrophobic molecules, meaning they do not dissolve in water. This property affects their absorption in the digestive system, where bile salts emulsify fats, allowing them to be broken down and absorbed by intestinal cells. Understanding this process is essential for grasping how dietary fats contribute to energy intake.

Health Implications of Dietary Fats vs. Carbohydrates

The health implications of consuming fats compared to carbohydrates can vary significantly based on the type of fat or carbohydrate. While some fats (like unsaturated fats) can be beneficial, others (like trans fats) can be harmful. Similarly, refined carbohydrates can lead to health issues, making it important to evaluate the quality of these macronutrients in the diet.