Final answer:
The total energy expenditure in a 24-hour period is made up of resting energy expenditure, the thermic effect of food, and the energy expended during physical activity.
Step-by-step explanation:
Resting energy expenditure (REE), the thermic effect of food (TEF), and physical activity-related energy expenditure are all components that contribute to one's 24-hour energy expenditure. REE accounts for the energy required at rest and is closely related to the basal metabolic rate (BMR), which represents the energy the body needs for basic functions. TEF refers to the energy expended in digesting, absorbing, and metabolizing food. Physical activity energy expenditure involves the extra energy used when engaging in any form of physical activity beyond resting. Together, these components calculate the total amount of energy an individual expends in a 24-hour period.