Chapter 2: Environmental Systems

Chapter 2: Environmental Systems

1. everything = matter

   • radioactivity/half-life
   • chemical bonds
     • covalent: shares e-
     • ionic: transfers e-
     • hydrogen bonds: very weak
   • properties of H2O
     • surface tension: "skin" on water's surface
     • larger volume in solid form than liquid
     • versatile solvent
   • law of conservation of matter: matter cannot be created/destroyed
   • biological molecules
     • proteins
     • nucleic acid, DNA, RNA
     • lipids
     • carbs

2. energy: ability to do work or transfer heat

   • most comes from Sun
     • electromagnetic radiation/photons
   • energy = power x time
   • potential energy: stored but not yet released
   • kinetic energy: energy of motion
     • temperature: measure of kinetic energy
   • 1st law of thermodynamics: energy is neither created/destroyed
   • 2nd law of thermodynamics: when energy is transformed, amount of energy is same, ability to do work lessens
     • systems work towards entropy (randomness)

3. energy conversions

   • amount/form of energy determines what kind of organisms can live there

4. Systems analysis shows how matter and energy flow in the environment

   • open vs closed systems
   • steady state: inputs = outputs
   • positive vs negative feedback loops

5. Natural systems change across space and over time

   • difference in environmental conditions
   • passage of time