Final answer:
Metabolic rate is the rate at which calories are burned to produce energy for sustaining life and supporting activities. Basal metabolic rate (BMR) measures energy use at rest, and diet affects energy requirements for processing different nutrients.
Step-by-step explanation:
Metabolic rate refers to the rate at which calories are burned to produce energy. This rate is integral to sustaining life and supporting various activities that an individual undertakes. The basal metabolic rate (BMR) is the rate at which the body uses energy while at rest to maintain vital functions such as maintaining core body temperature, which is tightly regulated by the hypothalamus in the brain. Our diet plays a significant role in our metabolic rate, as different nutrients like carbohydrates, proteins, and fats require varying amounts of energy to be processed. Moreover, in situations like starvation, our body prioritizes different energy sources such as glucose and proteins to sustain metabolic functions.