Fundamental Chemical Reactions in Biology

Understanding fundamental chemical reactions in biology is key to grasping how life functions. These reactions, like hydrolysis and oxidation-reduction, drive processes such as energy production, digestion, and genetic replication, connecting chemistry to the biological world around us.

1. Hydrolysis reactions

   • Involves the breaking of chemical bonds through the addition of water.
   • Essential for the digestion of macromolecules like proteins, carbohydrates, and lipids.
   • Plays a key role in cellular processes, such as ATP hydrolysis for energy release.

2. Condensation reactions

   • Also known as dehydration synthesis, where two molecules combine, releasing water.
   • Important for forming larger biological macromolecules, such as proteins and nucleic acids.
   • Facilitates the creation of peptide bonds between amino acids and glycosidic bonds in carbohydrates.

3. Oxidation-reduction (redox) reactions

   • Involves the transfer of electrons between molecules, changing their oxidation states.
   • Crucial for energy production in cellular respiration and photosynthesis.
   • Plays a role in metabolic pathways, including the Krebs cycle and electron transport chain.

4. Acid-base reactions

   • Involves the transfer of protons (H+) between molecules, affecting pH levels.
   • Important for maintaining homeostasis in biological systems and enzyme activity.
   • Key in metabolic processes, such as the regulation of bicarbonate in blood.

5. Phosphorylation reactions

   • The addition of a phosphate group to a molecule, often altering its activity or function.
   • Central to energy transfer processes, particularly in ATP and signal transduction pathways.
   • Plays a role in regulating metabolic pathways and enzyme activity.

6. Glycolysis

   • A series of enzymatic reactions that convert glucose into pyruvate, producing ATP and NADH.
   • Occurs in the cytoplasm and does not require oxygen (anaerobic process).
   • Serves as a key metabolic pathway for energy production in both aerobic and anaerobic organisms.

7. Krebs cycle (citric acid cycle)

   • A series of chemical reactions used by all aerobic organisms to generate energy.
   • Takes place in the mitochondria and processes acetyl-CoA to produce ATP, NADH, and FADH2.
   • Plays a critical role in the metabolic pathway, linking carbohydrate, fat, and protein metabolism.

8. Photosynthesis

   • The process by which green plants, algae, and some bacteria convert light energy into chemical energy.
   • Occurs in chloroplasts, using sunlight to convert carbon dioxide and water into glucose and oxygen.
   • Fundamental for the energy supply of nearly all life on Earth, forming the base of the food chain.

9. Protein synthesis

   • The process of translating genetic information from mRNA to build proteins.
   • Involves transcription (DNA to mRNA) and translation (mRNA to protein) in ribosomes.
   • Essential for cell structure, function, and regulation of biological processes.

10. DNA replication

    • The process of copying the DNA molecule to ensure genetic information is passed to daughter cells.
    • Involves unwinding the double helix and synthesizing new complementary strands.
    • Critical for cell division and maintaining genetic continuity across generations.