lawsoftheromo

GeneralBiologyOnline

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Ch. 6 Contents

General
---------Biology----------------------------------------------
------------------Online------------------------------wilcox@sunline.net Ch. 6 Metabolism of carbohydrates, fats, proteins, nucleic acids

3. The energy transformations of life are
subject to two laws of thermodynamics

Look up the definitions and write them below.
First Law: _______________________________________________________________.
Second Law: _____________________________________________________________.

"Thermo" come from the latin/greek word meaning energy. "Dynamic" comes from the latin/greek word meaning change.

As an example of the Second Law, only 25% of the energy in gasoline is converted into kinetic energy of a car.

Important!!! Most of the chemical energy in the gas is lost as heat and ultimately radiated out into space. This is true any time you convert or transform energy. This is a very important limiting factor in the universe, on a farm, in nutrition and in attempts to improve a society's standard of living. The second law of thermodynamics is like an unseen, greedy dictator, always standing beside us ready to take a whopping 45 to 90 percent of the energy out of every transformation.

The effort to develop more fuel efficient cars is just one way society is constantly trying to cheat the greedy dictator. Can you name another? _______________________________

As the children in Figure 6.2 of your text play on the slide, several energy transformations occur.

List the energy conversion in the following activities using kinetic, chemical and potential kinetic energy.

Activity From ? Energy To ? Energy
climbing the slide	chemical energy (food in muscles)	-kinetic energy (climbing up)
sitting on top then sliding down	-potential ________ energy	-________ energy

thermodynamics and order