COLLEGE PREP BIOLOGY CHAPTER 3 THE BIOSPHERE
3-1 WHAT IS ECOLOGY ECOLOGY IS THE STUDY OF INTERACTIONS AMONG ORGANISMS AND HOW THE ORGANISMS INTERACT WITH THEIR ENVIRONMENT THE BIOSPHERE CONTAINS THE COMBINED PORTIONS OF THE PLANET IN WHICH ALL LIFE EXISTS (LAND, WATER, AIR) INTERDEPENDENCE OF LIFE ON EARTH CONTRIBUTES TO THE EVER CHANGING BIOSPHERE
LEVELS OF ORGANIZATION INDIVIDUALPOPULATIONCOMMUNITYECOSYSTEMBI OMEBIOSPHERE A SPECIES IS A GROUP OF ORGANISMS SIMILAR TO ONE ANOTHER THAT CAN BREED TO PRODUCE FERTILE OFFSPRING A POPULATION INVOLVES MEMBERS OF THE SAME SPECIES LIVING IN THE SAME AREA COMMUNITIES INCLUDE DIFFERENT POPULATIONS THAT LIVE TOGETHER IN A DEFINED AREA (*ONLY LIVING THINGS*) ECOSYSTEMS ARE COLLECTIONS OF ALL ORGANISMS THAT LIVE IN A PARTICULAR PLACE IN ADDITION TO THE NONLIVING ENVIRONMENT A BIOME IS A GROUP OF ECOSYSTEMS THAT HAVE THE SAME CLIMATE (AVERAGE WEATHER)
Figure 3-2 Ecological Levels of Organization Section 3-1 Go to Section:
THREE ECOLOGICAL METHODS OBSERVING: ASKING QUESTIONS EXPERIMENTING: EXPERIMENTS ARE USED TO TEST HYPOTHESES; CAN BE DONE IN THE LABORATORY OR IN NATURAL ECOSYSTEMS (FIELD STUDIES) MODELING: HELPS SCIENTISTS GAIN INSIGHT INTO COMPLEX PHENOMENA (MATHEMATICAL FORMULAS) *ALL THREE APPROACHES RELY ON THE APPLICATION OF THE SCIENTIFIC METHOD!!! COMPLETE THE 3-1 ASSESSMENT ON PAGE 65, #1-4
3-2 ENERGY FLOW *ENERGY IS NEEDED TO POWER LIFE’S PROCESSES *THE FLOW OF ENERGY THROUGH AN ECOSYSTEM IS ONE OF THE MOST IMPORTANT FACTORS THAT DETERMINES THE SYSTEM’S CAPACITY TO SUSTAIN LIFE SUNLIGHT IS THE MAIN SOURCE OF ENERGY FOR LIFE ON EARTH OF ALL SUNLIGHT, LESS THAN 1% IS USED BY LIVING THINGS
AUTOTROPHS AUTOTROPHS USE ENERGY FROM THE ENVIRONMENT TO FUEL THE ASSEMBLY OF SIMPLE INORGANIC COMPOUNDS INTO COMPLEX ORGANIC MOLECULES (EXAMPLES: PLANTS, SOME ALGAE, BACTERIA) AUTOTROPHS A.K.A. PRODUCERS! SOME PRODUCERS CAPTURE ENERGY FROM THE SUN AND SOME CAPTURE CHEMICAL ENERGY; BOTH TYPES ARE ESSENTIAL TO THE FLOW OF ENERGY THROUGH THE BIOSPHERE
ENERGY FROM THE SUN PHOTOSYNTHESIS IS THE PROCESS WHERE AUTOTROPHS USE LIGHT ENERGY TO POWER CHEMICAL REACTIONS THAT CONVERT CARBON DIOXIDE (CO2) AND WATER (H2O) INTO OXYGEN (O2) AND CARBOHYDRATES (SUGARS AND STARCHES) PHOTSYNTHESIS ADDS OXYGEN TO EARTH’S ATMOSPHERE AND REMOVES CARBON DIOXIDE ON LAND, PLANTS DO THIS, IN THE OCEAN, ALGAE, AND IN SALT MARSHES, CYANOBACTERIA
LIFE WITHOUT LIGHT CHEMOSYNTHESIS IS THE PROCESS WHERE ORGANISMS USE CHEMICAL ENERGY TO PRODUCE CARBOHYDRATES (SEVERAL TYPES OF BACTERIA DO THIS) CHEMOSYNTHESIS TAKES PLACE IN VOLCANO VENTS ON THE DEEP OCEAN FLOOR OR IN HOT SPRINGS
EQUATION FOR PHOTOSYNTHESIS 6 CO2 + 6 H2O C6H12O6 + 6 O2 WHICH ELEMENT DOES C STAND FOR? O? H?
CONSUMERS A.K.A. HETEROTROPHS HETEROTROPHS ARE ANIMALS THAT CANNOT USE ENERGY DIRECTLY FROM THE SUN THEY RELY ON OTHER ORGANISMS FOR THEIR ENERGY AND FOOD SUPPLY TYPES OF HETEROTROPHS HERBIVORES: EAT PLANTS CARNIVORES: EAT ANIMALS OMNIVORES: EAT BOTH PLANTS AND ANIMALS DETRITIVORES: EAT ANIMAL REMAINS & DEAD MATTER DECOMPOSERS: EAT ORGANIC MATTER
FEEDING RELATIONSHIPS ENERGY FLOWS THROUGH AN ECOSYSTEM IN ONE DIRECTION, FROM SUN TO AUTOTROPHS TO HETEROTROPHS THE FOOD CHAIN IS A SERIES OF STEPS IN WHICH ORGANISMS TRANSFER ENERGY BY EATING AND BEING EATEN FOR EXAMPLE: PRAIRIE PRODUCER HERBIVORE CARNIVORE GRASS ANTELOPE COYOTE WHEN WE SEE “”, WE SAY “IS EATEN BY”
FEEDING RELATIONSHIPS CONTINUED A FOOD WEB CONTAINS ALL FEEDING RELATIONSHIPS LINKED TOGETHER IN AN ECOSYSTEM; IT CONTAINS MORE THAN ONE FOOD CHAIN LET’S LOOK AT FIGURE 3-8 ON PAGE 71 A TROPHIC LEVEL REPRESENTS EACH LEVEL IN A FOOD CHAIN OR FOOD WEB PRODUCERS ARE ALWAYS THE FIRST TROPHIC LEVEL CONSUMERS ARE SECOND, THIRD, OR HIGHER LEVELS EACH CONSUMER DEPENDS ON THE TROPHIC LEVEL BELOW IT FOR ENERGY
Figure 3-8 A Food Web A FOOD WEB Section 3-2 Go to Section:
ECOLOGICAL PYRAMIDS ECOLOGICAL PYRAMIDS ARE DIAGRAMS THAT SHOW THE RELATIVE AMOUNTS OF ENERGY OR MATTER CONTAINED WITHIN EACH TROPHIC LEVEL IN A FOOD CHAIN OR FOOD WEB
TYPES OF ECOLOGICAL PYRAMIDS Section 3-2 Energy Pyramid Shows the relative amount of energy available at each trophic level. Organisms use about 10 percent of this energy for life processes. The rest is lost as heat. Pyramid of Numbers Shows the relative number of individual organisms at each trophic level. Biomass Pyramid Represents the amount of living organic matter at each trophic level. Typically, the greatest biomass is at the base of the pyramid. Go to Section:
THREE TYPES OF ECOLOGICAL PYRAMIDS ENERGY PYRAMIDS: ONLY PART OF THE ENERGY STORED IN ONE TROPHIC LEVEL IS PASSED ON TO THE NEXT LEVEL *ORGANISMS USE WHAT THEY NEED FOR THEIR LIFE PROCESSES BEFORE PASSING ENERGY ON *ONLY 10% OF THE ENERGY AVAILABLE WITHIN ONE TROPHIC LEVEL IS TRANSFERRED TO THE ORGANISMS AT THE NEXT LEVEL FOR EXAMPLE: IF PRODUCERS GET 100% OF THE ENERGY FROM THE SUN, PRIMARY CONSUMERS WILL GET 10%, SECONDARY CONSUMERS WILL GET 1%, AND TERTIARY CONSUMERS WILL ONLY GET .1%!!!
ECOLOGICAL PYRAMIDS CONTINUED 2. BIOMASS PYRAMID: BIOMASS IS THE TOTAL AMOUNT OF LIVING TISSUE WITHIN A GIVEN TROPHIC LEVEL IT IS EXPRESSED IN TERMS OF GRAMS ORGANIC MATTER/UNIT AREA (THE GREATEST BIOMASS IS AT THE BASE OF A PYRAMID)
ECOLOGICAL PYRAMIDS CONTINUED 3. PYRAMID OF NUMBERS: CONTAINS THE NUMBERS OF INDIVIDUAL ORGANISMS AT EACH TROPHIC LEVEL
*LOOK AT THE ENERGY PYRAMID ON P 72. SUPPOSE THE BASE CONSISTS OF PLANTS THAT CONTAIN 450,000 CALORIES OF FOOD ENERGY. IF ALL THE PLANTS WERE EATEN BY MICE AND INSECTS, HOW MUCH FOOD ENERGY WOULD BE AVAILABLE TO THOSE FIRST LEVEL CONSUMERS? 45,000 CALORIES IF ALL MICE AND INSECTS WERE EATEN BY SNAKES, HOW MUCH FOOD ENERGY IS AVAILABLE TO THE SNAKES? 4,500 CALORIES IF SNAKES WERE EATEN BY A HAWK, HOW MUCH FOOD ENERGY IS AVAILABLE TO THE HAWK? 450 CALORIES
COMPLETE THE GUIDED READING WORKSHEETS FOR CHAPTER 3 SECTION 2!!! HOW MUCH FOOD ENERGY WOULD THE HAWK USE FOR ITS BODY PROCESSES AND LOSE AS HEAT? 405 CALORIES (90% OF 450) HOW MUCH FOOD ENERGY WOULD BE STORED IN THE HAWKS BODY? 45 CALORIES COMPLETE THE GUIDED READING WORKSHEETS FOR CHAPTER 3 SECTION 2!!!
3-3 CYCLES OF MATTER IN MOST ORGANISMS, MORE THAN 95% OF THE BODY IS MADE UP OF FOUR ELEMENTS: OXYGEN, CARBON, HYDROGEN, AND NITROGEN. MATTER IS RECYCLED WITHIN AND BETWEEN ECOSYSTEMS IN THE BIOSPHERE. BIOGEOCHEMICAL CYCLES ARE PROCESSES WHERE ELEMENTS, CHEMICAL COMPOUNDS, AND OTHER FORMS OF MATTER ARE PASSED FROM ONE ORGANISM TO ANOTHER. THE SAME MOLECULES ARE PASSED AROUND AGAIN AND AGAIN WITHIN THE BIOSPHERE.
THE WATER CYCLE The Water Cycle Section 3-3 Go to Section: Condensation Precipitation Transpiration Evaporation Runoff Seepage Root Uptake Go to Section:
THE WATER CYCLE CONTINUED EVAPORATION: THE PROCESS BY WHICH WATER IS CHANGED FROM LIQUID TO GAS TRANSPIRATION: THE EVAPORATION OF WATER FROM THE LEAVES OF PLANTS *WHAT PROCESS IN HUMANS AND OTHER MAMMALS RELEASES WATER VAPOR INTO THE AIR? RESPIRATION!
NUTRIENT CYCLES NUTRIENTS INCLUDE ALL THE CHEMICAL SUBSTANCES THAT AN ORGANISM REQUIRES TO LIVE. EVERY LIVING ORGANISM NEEDS NUTRIENTS TO GROW AND CARRY OUT ESSENTIAL LIFE FUNCTIONS. LIKE WATER, NUTRIENTS ARE PASSED BETWEEN ORGANISMS AND THE ENVIRONMENT THROUGH BIOGEOCHEMICAL CYCLES.
THE CARBON CYCLE (THE 1ST NUTRIENT CYCLE) CARBON IS THE KEY INGREDIENT IN ALL LIVING ORGANISMS. LESS THAN 1% OF ALL CARBON ON EARTH ACTIVELY CIRCULATES WITHIN THE BIOSPHERE BIOLOGICAL PROCESSES: PHOTOSYNTHESIS, RESPIRATION, AND DECOMPOSITION GEOCHEMICAL PROCESSES: RELEASING CARBON DIOXIDE GAS INTO THE ATMOSPHERE MIXED BIOGEOCHEMICAL PROCESSES: BURIAL OF CARBON REMAINS OF ORGANISMS AND THEIR CONVERSION TO COAL BY PRESSURE OF EARTH HUMAN ACTIVITY: MINING, BURNING FOSSIL FUELS
THE CARBON CYCLE Figure 3-13 The Carbon Cycle Section 3-3 CO2 in Atmosphere CO2 in Ocean Go to Section:
THE NITROGEN CYCLE (THE 2ND NUTRIENT CYCLE) NITROGEN IS USED TO MAKE AMINO ACIDS WHICH ARE THE BUILDING BLOCKS OF PROTEINS. FORMS OF NITROGEN: NITROGEN GAS MAKES UP 78% OF THE EARTH’S ATMOSPHERE AMMONIA: FOUND IN WASTES PRODUCED BY ORGANISMS NITRATE IONS AND NITRITE IONS: FOUND IN WASTES PRODUCED BY ORGANISMS NITRATE: PLANT FERTILIZERS ADDED BY HUMANS
THE NITROGEN CYCLE BACTERIA USE NITROGEN GAS AND CONVERT IT INTO AMMONIA. THIS IS CALLED NITROGEN FIXATION. OTHER BACTERIA CONVERT AMMONIA INTO NITRATES AND NITRITES PRODUCERS USE NITRATES AND NITRITES TO MAKE PROTEINS CONSUMERS EAT PRODUCERS AND REUSE NITROGEN TO MAKE THEIR OWN PROTEINS ORGANISMS DIE AND DECOMPOSERS RETURN NITROGEN TO THE SOIL AS AMMONIA AMMONIA IS TAKEN UP BY PRODUCERS BACTERIA IN THE SOIL CONVERT AMMONIA INTO NITROGEN GAS. THIS IS CALLED DENITRIFICATION. NITROGEN GAS IS RELEASED INTO THE ATMOSPHERE AGAIN AND THE CYCLE CONTINUES
THE NITROGEN CYCLE Figure 3-14 The Nitrogen Cycle NO3- and NO2- NH3 Section 3-3 N2 in Atmosphere NO3- and NO2- NH3 Go to Section:
THE PHOSPHORUS CYCLE (THE 3RD NUTRIENT CYCLE) PHOSPHATE FORMS PARTS OF DNA AND RNA PHOSPHATE DOESN’T ENTER THE ATMOSPHERE; IT REMAINS ON LAND IN THE SOIL AND ROCK. AS THE ROCKS WEAR DOWN, PHOSPHATE IS RELEASED. ON LAND, PHOSPHATE IS WASHED INTO RIVERS AND STREAMS WHERE IT DISSOLVES. IT CAN THEN BE USED BY MARINE ORGANISMS. PHOSPHATE IN THE SOIL CAN BE ABSORBED B Y PLANTS AND BE USED TO FORM ORGANIC COMPOUNDS. PHOSPHATE MOVES THROUGH THE FOOD WEB AS CONSUMERS EAT PRODUCERS
NUTRIENT LIMITATION PRIMARY PRODUCTIVITY: THE RATE AT WHICH ORGANIC MATTER IS CREATED BY PRODUCERS. PRIMARY PRODUCTIVITY IS CONTROLLED BY THE AMOUNT OF AVAILABLE NUTRIENTS FOR EXAMPLE, IF A NUTRIENT IS IN SHORT SUPPLY, IT WILL LIMIT THE ORGANISMS GROWTH A LIMITING NUTRIENT IS WHEN AN ECOSYSTEM IS LIMITED BY A SINGLE NUTRIENT THAT IS SCARCE OR CYCLES SLOWLY
COMPLETE CHAPTER 3 SECTION 3 GUIDED READING WORKSHEETS!!! FERTILIZERS BOOST THE PRODUCTIVITY OF CROPS. THEY CONTAIN NITROGEN, PHOSPHORUS, AND POTASSIUM, WHICH ALL HELP PLANTS GROW LARGER AND MORE QUICKLY THAN THEY WOULD IF THEY WERE IN UNFERTILIZED SOIL. NITROGEN, SILICON, AND IRON ARE LIMITING NUTRIENTS IN SALTWATER ENVIRONMENTS. PHOSPHATE IS A LIMITING NUTRIENT IN FRESHWATER ENVIRONMENTS. AN ALGAL BLOOM INVOLVES AN IMMEDIATE INCREASE IN THE AMOUNT OF ALGAE AND OTHER PRODUCERS DUE TO LARGE AMOUNTS OF A LIMITING NUTRIENT COMPLETE CHAPTER 3 SECTION 3 GUIDED READING WORKSHEETS!!!