Chapter 27, Problem 1P

Interpretation Introduction

Interpretation : Food consumed by the lady in 40 years should be calculated.

Concept Introduction : The amount of energy required to balance the energy loss to maintain the body size, composition, and level of physical activity is termed as energy requirement. Energy in the human body is derived from macronutrients, such as carbohydrates, fats, ethanol, and proteins.

Answer to Problem 1P

Food consumed by the lady in 40 years is 3200kg.

Explanation of Solution

Given information :

A woman’s weight does not change from the ages of 25 to 65. She requires 8,400 kJ (2000 kcal) per day. The energy density of fatty acids is 38kJ (9kcal) g -1.

The amount of food ingested by the woman in 40 years is

  $\begin{array}{c}\text{Amount of calories consumed by woman = No}\text{. of years }\times \frac{\text{365days}}{\text{year}}\times \text{ no}\text{. of calories taken in one year}\\ \text{ = 40 years}\times 365\text{ days }\times \text{ 8400 kJ/day }\\ \text{ = 1}\text{.2 }\times {\text{ 10}}^8\text{kJ }\\ \text{Total amount of food ingested in 40 years = }\frac{\text{1}\text{.2}\times {\text{10}}^8\text{kJ }}{38{\text{kJ g}}^{-1}}\\ \text{= 3}\text{.2}\times {\text{10}}^6\text{ g}\\ \text{ = 3200kg }\end{array}$

Conclusion

Food consumed by the lady in 40 years is 3200kg.