Food and Heat
Name: Tasha P.
How does food produce heat in the body?
The potential energy of food is released when it is "burned" by the body's metabolic processes.
In fact, the processes involved extend all the way back to the sun. Sunlight provides the
energy necessary to enable green (photosynthesizing) plants to grow as they convert carbon
dioxide, water, and other nutrients into plant tissue that itself represents a kind of energy
storehouse. We can access that stored energy when we eat those plants -- or animals that have
eaten plants. In the end, our metabolic processes release some of the food energy as heat as
we convert the food back into carbon dioxide, water, and other products from the processes
that enable us to thrive, grow, and repair injuries to our body. So, in a sense, the body is
Energy must be generated in order life to be
maintained. Heat is a form of energy.
As you said energy is generated from the food eaten
This is done by a highly integrated network of
chemical reactions that receive the collective name
A scientist named Hans Krebs described 3 stages in the
generation of energy from the oxidation of foodstuffs.
-In the first stage, large molecules in food are
broken down to smaller units. Proteins are hydrolyzed
to their twenty constituent amino acids,
polysaccharides are hydrolized to simple sugars, as
glucose, and fats are hydrolized to glycerol and fatty
acids. In that phase no useful energy is generated.
- In the second stage, these numerous small molecules
are degraded to a few simple units that play a central
role in metabolism. Most of them sugars, fatty acids,
glycerol and many amino acids are converted into the
acetyl unit of the acethyl CoA.
- The third stage consists of the citric acid cycle
and oxidative phosphorilation, which are the final
commom pathways in the oxidation of fuel molecules
when they are completely oxidized to CO2 and ATP
(Adenosine triphosphate) is generated as electrons
flow from the reduced forms of these carriers to O2,
completing the process.
Thanks for asking NEWTON!
(Dr. Mabel Rodrigues)
All food energy comes from sunlight. In photosynthesis, plants capture solar energy and use
it to make large, energy-rich molecules from smaller, simpler ones. The sun's energy is
converted to chemical energy that is stored within the structures of these molecules. We
recover some of this stored energy when we eat the plants--or dine on meat and dairy products
from animals that consumed green plants. When these energy giving chemicals are digested,
some of these chemical are further broken down in your body's cells and converted into heat
I hope that this helps.
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Update: June 2012