2.3 Energy for Life

• Chemosynthesis; the synthesis of organic compounds by bacteria or other living organisms using energy derived from reactions involving inorganic chemicals, typically in the absence of sunlight
• Extremophiles; organisms that live in "extreme environments"
• Sun; a fiery ball of exploding hydrogen gas
• Photosynthesis; the process by which green plants and certain organisms transforms light energy into chemical energy
• The light coming from the sun contains 10% ultraviolet light, 45% infrared light, and 45% visible light.
• Photosynthetically Active Radiation; the amount of light available for photosynthesis
• Who can Photosynthesize?

  • Some Protists
  • Some Bacteria
  • Plants
• Chloroplast; chlorophyll containing organelle in eukaryotic organisms; sites of Photosynthesis
• Chlorophyll; a unique green molecule that can absorb light energy and use it to create high-energy chemical bonds in compound that serve as the fuel for all subsequent cellular metabolism
• Pigments; Light - capturing molecules
• Example of Pigments;

  • Carotene
  • Anthocyanin
  • Xanthophyll
• Cellular Respiration; a metabolic pathway that breaks down glucose and produces ATP. It occurs in the mitochondria
• Mitochondria; the powerhouse of the cell
• Cellular Respiration; the process of releasing chemical energy that involves splitting carbon and hydrogen atoms from the sugar molecule and recombining them with oxygen to re-create carbon dioxide and water
• Electromagnetic Spectrum:

  1. 10% ultraviolet
  2. 45% infrared
  3. 45% visible