Energy and Metabolism
Introduction:
Energy is the basic requirement for living organisms. It drives all biological processes, including growth, reproduction, movement, and maintenance of life. Metabolism is a term used to describe the chemical reactions that occur within cells to convert the energy stored in nutrients into a form that can be used by cells.
Key Concepts:
- ATP: Adenosine Triphosphate is the molecule that typically provides energy to cells. Energy is stored in the high-energy bond between the second and third phosphate group, which is released when this bond is broken by hydrolysis.
- Catabolism: The breakdown of molecules (such as glucose) into smaller components releases energy, which can be used to make ATP.
- Anabolism: The synthesis of molecules (such as proteins) requires energy, which can be supplied by ATP hydrolysis.
- Enzymes: Biological catalysts that speed up chemical reactions, allowing catabolic and anabolic reactions to occur at appropriate rates.
Equations and Formulas:
- Cellular Respiration: C6H12O6 (glucose) + 6O2 → 6CO2 + 6H2O + energy (ATP)
- Photosynthesis: 6CO2 + 6H2O + light energy → C6H12O6 (glucose) + 6O2
Examples:
- The process of digestion breaks down carbohydrates into glucose molecules, which are then used in cellular respiration to produce ATP.
- The process of photosynthesis produces glucose molecules, which can be used for energy as well as for the synthesis of other molecules.
References for Further Learning:
- “Bioenergetics and Metabolism” by Dr. Reginald Garrett and Dr. Charles Grisham
- “Biochemistry” by Dr. Lubert Stryer
- “Molecular Biology of the Cell” by Dr. Bruce Alberts and colleagues.
