Free Energy

     On earth, in order for living organisms to maintain life, all living systems require energy. Energy is a very interesting topic because without energy we would not have any order, growth, or reproduction. Although not all organisms use the same methods to maintain order, energy will always be required for that matter. In fact, organisms use various energy-related strategies to survive; For example, some include different metabolic rates, physiological changes, and variations in reproductive and offspring-raising strategies. With the lack of energy this would cause devastating deficiencies to individual organisms, also the changes in free energy can impact heavily the population size and cause huge disturbances at the ecosystem level.

        There have been many methods to capture, use and store free energy that have evolved within organisms. Cells are able to capture free energy through two methods either photosynthesis or chemosynthesis. Autotrophs, who are your plant organisms feed themselves by capturing free energy from the environment, including the energy that comes from the sun and chemical sources. On the contrary heterotrophs harvest free energy from carbon compounds produced by other organisms. So the difference between autotrophs and heterotrophs is simply that autotrophs provide themselves with food (energy) and heterotrophs rely on other organism for their income as food (energy). Photosynthetic organisms capture energy present in  sunlight while chemo-synthetic organisms capture free energy from small inorganic molecules present in their environment  and this can happen in the absence of oxygen these are two methods used by autotrophic organisms. Heterotrophs metabolize carbohydrates,lipids, and proteins by hydrolysis as a source of  free energy.

Willard Gibbs

If you take a took to the left, you will see one of the most profound men in science. This genius by the name Willard Gibbs is responsible for the Gibbs free energy equation used in thermodynamics. the Gibbs free energy is a thermodynamic potential that measures the "usefulness" from a thermodynamic system at a constant temperature and pressure.To get a better understanding of Gibbs equation you must know the laws of thermodynamic. The laws of thermodynamics define the laws which temperature,energy, and entropy go under.The first law of thermodynamics which is also known as the law of conservation of energy states that energy cannot be created nor destroyed. The second law of thermodynamics says that the entropy in any isolated system not in thermal equilibrium almost always increases. The third law says that the entropy of a system approaches a constant value as the temperature approaches an absolute zero. Entropy is the lack of order within a thermodynamic system and enthalpy is a thermodynamic quantity that shows the total heat content of a system.

that energy cannot be created or destroyed in a chemical reaction.

Source: Boundless. “The Three Laws of Thermodynamics.” Boundless Chemistry. Boundless, 16 Nov. 2014. Retrieved 30 Nov. 2014 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/thermodynamics-17/the-laws-of-thermodynamics-123/the-three-laws-of-thermodynamics-496-3601/

that energy cannot be created or destroyed in a chemical reaction.

Source: Boundless. “The Three Laws of Thermodynamics.” Boundless Chemistry. Boundless, 16 Nov. 2014. Retrieved 30 Nov. 2014 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/thermodynamics-17/the-laws-of-thermodynamics-123/the-three-laws-of-thermodynamics-496-3601/

Gibbs free energy equation.

The AP Biology curriculum framework 2012-2013 is a great guide for such a hefty topic. I would suggest for you to click the link below. The curriculum gives a satisfying in depth understanding to the growth, reproduction, and maintenance of organization of living systems requiring free energy and matter. Once you click the link below follow through pages 15-22 for extra details such as the the whole process of different energy-related pathways in biological systems. 






 AP Biology Curriculum Framework 2012-2013



Sources

 AP BIOLOGY (n.d.): n. pag. Web.

 

"No. 119: J. Willard Gibbs." No. 119: J. Willard Gibbs. N.p., n.d. Web. 30 Nov. 2014.

 

 

"Chemical Thermodynamics." Gibbs Free Energy. N.p., n.d. Web. 30 Nov. 2014.

 

"Gibbs Free Energy." Gibbs Free Energy. N.p., n.d. Web. 29 Nov. 2014.