GENERAL HISTOLOGY

Detailed explanation-1: -This is the accepted standard unit of energy used in human energetics and it should also be used for the expression of energy in foods. Because nutritionists and food scientists are concerned with large amounts of energy, they generally use kiloJoules (kJ = 103 J) or megaJoules (MJ = 106 J).

Detailed explanation-2: -The International System of Units (SI) unit for energy is the joule; however, the calorie is commonly used for a unit of food energy. A calorie is equal to the amount of energy per unit mass required to raise the temperature of 1 g of water by 1° C. One calorie is the equivalent of 4.18 joules.

Detailed explanation-3: -Calories are a measure of energy in nutrition and exercise. Calories and kcal are used interchangeably and refer to the same amount of energy. Calories or kcal may also be measured in kJ, with one calorie (kcal) equaling 4.18 kJ.