Natural Resources

• Natural resources


  Substances or materials that occur naturally in the environment and are used by humans for various purposes
• Abiotic resources


  • Minerals
  • Non-metallic minerals
  • Water
  • Soil
  • Air
• Minerals


  Iron, copper, gold, silver, uranium
• Non-metallic minerals


  Salt, gypsum, sand, gravel
• Water


  Freshwater (rivers, lakes, groundwater), saltwater (oceans, seas)
• Soil


  Essential for agriculture and plant growth
• Air


  Oxygen, nitrogen, carbon dioxide
• Biotic resources


  • Plants
  • Animals
  • Microorganisms
• Animals


  Livestock, fish, wildlife
• Microorganisms


  Bacteria, fungi, algae
• Biochemical cycle (system)


  Succession of interrelated chemical reactions that occur within an organism or environment
• Inputs of biochemical cycles

  • Molecules, substrates, or energy sources that start or feed the cycle
  • Frequently obtained from the environment or from other metabolic processes within the organism
• Outputs of biochemical cycles

  • Products or intermediates generated as a result of the cycle's activity
  • May serve various purposes within the organism, such as providing building blocks for cellular structures, generating energy in the form of ATP, or serving as signaling molecules for cellular communication
• Growing system


  Has more inputs than outputs
• Declining system


  Has less inputs than outputs
• Negative feedback


  • Helps to preserve stability by compensating for any deviation from the set point
  • When a change in a parameter is recognised, the system launches an opposing response, bringing the parameter back to the set point
• Positive feedback


  • Improves or supports parameter changes rather than opposing them
  • This might result in a cascade effect, in which the parameter continues to deviate from the set point until an external factor breaks the loop
• Positive feedback


  • Blood clotting
  • Release of oxytocin during labour
• Matter on earth is limited, it is used over and over again
• Common cycles of matter

  • Water
  • Carbon
  • Nitrogen