Class IX Biology - Chapter: Nutrition - Topic: Caloric Value Numerical Problems

Problem 1: Calculating Energy from Food Components

A food sample contains 10g of carbohydrates, 5g of proteins, and 3g of fats. Calculate the total energy (in kcal) provided by this food sample.

Solution:

We use the approximate physiological fuel values:

• Carbohydrates: 4 kcal/g
• Proteins: 4 kcal/g
• Fats: 9 kcal/g

Energy from carbohydrates = 10g * 4 kcal/g = 40 kcal Energy from proteins = 5g * 4 kcal/g = 20 kcal Energy from fats = 3g * 9 kcal/g = 27 kcal

Total energy = 40 kcal + 20 kcal + 27 kcal = 87 kcal

Therefore, the food sample provides a total of 87 kcal of energy.

Problem 2: Daily Calorie Requirement

An adult male requires approximately 2500 kcal per day. If he consumes a meal providing 750 kcal, what percentage of his daily calorie requirement has he fulfilled with this meal?

Solution:

Percentage fulfilled = (Calories consumed in meal / Daily calorie requirement) * 100 Percentage fulfilled = (750 kcal / 2500 kcal) * 100 Percentage fulfilled = 0.3 * 100 = 30%

Therefore, the meal fulfilled 30% of his daily calorie requirement.