Unit 3 - Energy and Matter

Unit 3 - Matter and Energy

Biogeochemical Cycles

Recycling in the Biosphere

• Matter is recycled within and between the ecosystems

  Biochemical cycles: how matter is passed from one organism to another and from one part of the biosphere to another

  Biological systems do not use up matter, they transform it:

  o  Assembled into living tissue

  o  Passed out of the body as waste products 

Introduction to the Cycles

• Organisms need water, minerals, and other compounds too

• 95% of most organisms are made up of just 4 element:

• Oxygen

• Carbon

• Hydrogen

• Nitrogen

The Water Cycle (continued)

• As warm moist air rises it cools and forms clouds

• When the droplets become large enough, the water returns to Earth’s surface in the form of precipitation

• The rain eventually enters a river or stream, and then runs off to the ocean;

  Some of the rain seeps into the soil, some goes to ground water, while some is absorbed by plants 

The Water Cycle

• All living things require water

• Water moves between the ocean, atmosphere, and land

• Evaporation is the process where water changes from liquid form to an atmospheric gas

• Water can also enter the atmosphere by evaporating from leaves of a plant in the process of transpiration

Nutrient Cycles

• All the chemical substances that an organism needs to sustain life are its nutrient

• Primary producers usually obtain nutrients in simple inorganic forms from their environment 

• Consumers obtain nutrients from eating other organisms 

  ·  Three important cycles are:

  o  Carbon cycle

  o  Nitrogen cycle

  o  Phosphorus cycle 

Carbon Cycle

• Carbon is a key ingredient of living tissue

• Four main types of processes move carbon through its cycle:

  o  Biological process: photosynthesis, respiration, and decomposition take up & release CO2 and O2

  o  Geochemical processes, such as erosion and volcanic activity release CO2 into the atmosphere and oceans     

  o  Mixed biogeochemical:

  ** Burial and decomposition of dead organisms

  ** processes, how coal and oil was made

  o  Human activities, mining, burning fossil fuels release CO2 

Click on each step of the Carbon Cycle to see where the Carbon goes