Energy Flashcards
Explain the process of a bomb calorimeter.
The sample is combusted in an oxygen-rich environment within the calorimeter, and the resulting heat is transferred to surrounding water. By measuring the temperature change in the water, the energy released by the food (measured in calories or joules) can be calculated.
What is the purpose of a bomb calorimeter?
Provides the gross energy (GE) of the food, which represents the total energy contained.
Define digestible energy.
The portion of GE that is digestible, calculated as GE minus energy lost in feces.
Define metabolisable energy.
DE minus energy lost in urine and gases.
Define net energy.
ME minus the energy expended for heat increment (energy lost as heat during digestion and metabolism); represents energy available for maintenance, growth, reproduction, etc.
Define BMR.
The energy expended by an animal at rest, in a thermoneutral environment, after fasting.
Define FMR.
Energy expenditure of an animal that is awake, at rest, and fasted.
Define maintenance metabolic rate.
The energy required to maintain current body weight and basic physiological functions without growth or activity.
Compare metabolic rates of larger and smaller animals.
Larger animals have lower metabolic rates per unit body weight compared to smaller animals.
Name the two methods used to measure metabolic rate.
Direct calorimetry, indirect calorimetry
