ECOSYSTEMS AND ENERGY
CHAPTER 2P.52-60
ENERGYTHE ABILITY TO DO WORK OR CAUSE CHANGE
TYPES OF ENERGY
1. POTENTIALSTORED ENERGY(BEFORE THE PITCHER RELEASES THE BALL) 2. KINETICENERGY OF MOTION(THE PITCHED BALL)
3. CHEMICALFROM ORGANIC MOLECULES, NUTRIENTS(PHOTOSYNTHESIS, CHEMOSYNTHESIS)
4. FREEENERGY NEEDED FOR A CELL TO WORK (SUCH AS FROM ATP)*EAT FOODGLUCOSEATP*
ORGANISMS THAT NEED ENERGY• AUTOTROPHSMAKE THEIR OWN FOOD SUCH AS PLANTS USING LIGHT FOR PHOTOSYNTHESIS ARE CALLEDPHOTOAUTOTROPHS ENERGY USING CHEMICALS (CHEMOSYNTHESIS) SUCH AS BACTERIA ARE CALLEDCHEMOAUTOTROPHS
• HETEROTROPHSCANNOT MAKE THEIR OWN FOOD AND MUST OBTAIN IT SUCH AS ANIMALS, FUNGI AND MOST BACTERIA **BOTH AUTOTROPHS AND HETEROTROPHS USE CELLULAR RESPIRATION IN ORDER TO RELEASE ENERGY FOR CELLS TO STAY ALIVE (GLUCOSEATP)
**BOTH STORE ENERGY (CHEMICAL ENERGY) AND USE SOME OF IT TO DO WORK (FREE ENERGY)
ECOSYSTEM STRUCTURE
1. PRODUCERS (AUTOTROPHS SUCH AS PLANTS)2. CONSUMERS (HETEROTROPHS SUCH AS HERBIVORES, CARNIVORES, OMNIVORES)3. DECOMPOSERS (HETEROTROPHS SUCH AS BACTERIA, FUNGI)
*THESE BREAKDOWN AND RECYCLE MATTER FOR NUTRIENTS*
FOOD CHAINS
• SHOW ENERGY FLOW BASED UPON WHAT ORGANISMS EAT
• EXAMPLE: GRASSRABBITSNAKEHAWK
TROPHIC LEVELS
• PRODUCERUSUALLY PLANTS• CONSUMERPRIMARY/1STORDER• CONSUMERSECONDARY/2ND ORDER • CONSUMERTERTIARY/3RDORDER• CONSUMERQUATERNARY/4TH ORDER
FOOD WEBS
• MADE UP OF MANY FOOD CHAINS • SHOWS THE INTERACTIONS BETWEEN THE
MEMBERS OF AN ECOSYSTEMFOR ENERGY AND NUTRIENTS
• FROM PRODUCERS TO CONSUMERS (BOTTOM TO TOP)
2 LAWS OF THERMODYNAMICS
P.57-60
2 LAWS OF THERMODYNAMICS
1. ENERGY CANNOT BE CREATED OR DESTROYED BUT CAN CHANGE FORM (LAW OF CONSERVATION OF ENERGY)
2. SYSTEMS TEND TO CHANGE IN A WAY THAT INCREASES DISORDER (ENTROPY) OF THE SYSTEM AND ITS SURROUNDINGS– FREE ENERGY INCREASES, ENTROPY DECREASES – FREE ENERGY DECREASES, ENTROPY INCREASES
*ORGANISMS OVERCOME THIS TENDENCY FOR INCREASED ENTROPY BY OBTAINING ENERGY
PYRAMIDS OFENERGY, BIOMASS, AND NUMBERS
• AT THE BASE OF EACH ARE THE PRODUCERS FOLLOWED BY THE CONSUMERS
• AS YOU GO FROM THE BOTTOM TO THE TOP, ALL 3 DECREASE
Levels of OrganizationBiosphere
Ecosystem Community
Population Organism
Biosphere
• Broadest, most inclusive level• Thin volume of Earth and its atmosphere that
supports all life• 20km (13mi) thick• 8-10 km (5-6mi) deep
into oceans• Comparable to skin
only of ENTIRE apple
Ecosystems • Includes all organisms and the non-living environment
found in a particular place• Ex: Pond– Living• Fish, aquatic
plants, algae, bacteria, etc
– Nonliving• Water, sunlight,
rocks
Community• All interacting organisms living in an area• Look at how species interact• How interactions
influence nature of community
• Ex: Pond– How fish
interact with plants, algae, bacteria
Populations • Includes all members of a species that live in
one place at one time • Ex: Pond– Rainbow trout
of THAT SPECIFIC POND
Organism • Simplest level• Look at behavioral adaptations that allow
organism to overcome obstacles
• Ex: Pond– One specific
rainbow trout