Respiration (DP IB Environmental Systems & Societies (ESS))

Respiration

• Respiration is the conversion of organic matter into carbon dioxide and water in all living organisms, releasing energy

  • Cellular respiration releases energy from glucose by converting it into a chemical form that can easily be used in carrying out active processes ( such as growth and repair) within living cells

  • The aerobic respiration reaction is:

Aerobic respiration

• The inputs and outputs are:

  • Inputs: organic matter (glucose) and oxygen

  • Processes: oxidation processes inside cells

  • Outputs: release of energy for work (movement) and heat

  • Transformations: stored chemical energy is transformed into kinetic energy and heat

• Some of the chemical energy released during cellular respiration is transformed into heat

  • Heat is generated by cellular respiration because it is not 100% efficient at transferring energy from substrates, such as carbohydrates, into the chemical form of energy used in cells

  • Heat generated within an individual organism cannot be transformed back into chemical energy and is ultimately lost from the body

  • The heat energy released increases the entropy in the ecosystem, following the second law of thermodynamics, while enabling organisms to maintain relatively low entropy (high organisation)