Energy
Energy balance is the homeostasis of energy in living systems. It is measured with the following equation:
Energy intake = internal heat produced + external work + storage.
When calculating energy balances in the body, energy is often measured in calories, with the definitions of a calorie falling into two classes:
- The small calorie or gram calorie (symbol: cal) approximates the energy needed to increase the temperature of 1 gram of water by 1 °C. This is about 4.2 joules.
- The large calorie, kilogram calorie, dietary calorie or food calorie (symbol: Cal) approximates the energy needed to increase the temperature of 1 kilogram of water by 1 °C. This is exactly 1,000 small calories or about 4.2 kilojoules.
Read more about this topic: Human Homeostasis
Famous quotes containing the word energy:
“For infants and toddlers learning and living are the same thing. If they feel secure, treasured, loved, their own energy and curiosity will bring them new understanding and new skills.”
—Amy Laura Dombro (20th century)
“Violence among young people ... is an aspect of their desire to create. They don’t know how to use their energy creatively so they do the opposite and destroy.”
—Anthony Burgess (b. 1917)
“Just as we are learning to value and conserve the air we breathe, the water we drink, the energy we use, we must learn to value and conserve our capacity for nurture. Otherwise, in the name of human potential we will slowly but surely erode the source of our humanity.”
—Elaine Heffner (20th century)