Ecosystem Recycling Headings Vocabulary Important Info ENERGY FLOWS
Ecosystem Recycling Headings Vocabulary Important Info
• ENERGY FLOWS THROUGH ECOSYSTEM • WATER—NITROGEN—CARBON—PHOSPHORUS ARE RECYCLED!!! • THEY MOVE THRU A BIOGEOCHEMICAL CYCLE: • ABIOTIC (non-living) PORTION OF ENVIRONMENT (ATMOSPHERE) LIVING THINGS THEN BACK AGAIN
Water Cycle • CELLS CONTAIN 70 -90% H 20 • VERY LITTLE OF EARTHS AVAILABLE H 20 IS IN LIVING THINGS • RIVERS / LAKES / STREAMS / OCEANS CONTAIN A BIG % • ATMOSPHERE CONTAIN WATER = WATER VAPOR • GROUND WATER = IN SOIL OR UNDERGROUND IN POROUS ROCK • WATER CYCLE = MOVEMENT OF H 20 B/T RESERVOIRS – EVAPORATION – TRANSPIRATION – PRECIPITATION
Evaporation • ADDS H 20 VAPOR TO ATMOSPHERE • HEAT CAUSES WATER TO EVAPORATE • 90% OF EVAPORATED WATER FROM TERRESTRIAL ECOSYSTEM PASSES THROUGH PLANTS IN A PROCESS CALLED…
Transpiration • PLANTS TAKE IN H 20 THRU ROOTS • RELEASE WATER & TAKE IN CO 2 (CARBON DIOXIDE) • ANIMALS DRINK/ EAT TO TAKE IN H 20 • ANIMALS RELEASE IT WHEN: – BREATHING – SWEATING – EXCRETION
Precipitation • WATER LEAVES ATMOSPHERE • TEMP & AIR PRESSURE (ABIOTIC FACTORS) DETERMINE HOW MUCH WATER CAN BE HELD • ONCE ATM. IS SATURATED W/VAPOR = – SNOW, RAIN, SLEET, HAIL OR FOG
Carbon Cycle • PHOTOSYNTHESIS + CELLULAR RESPIRATION • PHOTOSYNTHESIS = PLANTS & OTHER AUTOTROPHS USE: • CO 2 + H 20 & SUNLIGHT = CARBOHYDRATES
CELLULAR RESPIRATION • PROCESS IN WHICH AUTOTROPHS & HETEROTROPHS USE OXYGEN (O 2) TO BREAKDOWN CARBS. • CELLS MAKE ATP (ENERGY) BY BREAKING DOWN ORGANIC COMPOUNDS – A COMPOUND THAT RESULTS FROM LIVING THINGS & CONTAINS CARBON
HUMAN INFLUENCE ON THE CARBON CYCLE • IN THE PAST 150 YEARS CO 2 IN THE ATMOSPHERE HAS RISEN 30% ALMOST ½ IN THE LAST 40 YEARS • DUE TO HUMANS ACTIVITY • BURNING FOSSIL FUEL: – REMAINS OF ORGANISMS THAT HAVE BEEN TRANSFORMED BY DECAY, HEAT, & PRESSURE • ENERGY RICH ORGANIC MOLECULES
• BURNING RELEASES ENERGY & CO 2 • BURNING VEGETATION RELEASES CO 2 • TROPICAL RAINFOREST DESTRUCTION • WITH NO PLANTS CO 2 IS NOT ABSORBED
Nitrogen Cycle • NITROGEN IS NEEDED TO MAKE PROTEINS & NUCLEIC ACIDS: • ORGANIC MOLECULE, DNA OR RNA, THAT STORES & CARRIES IMPORTANT INFO FOR CELL FUNCTION • N 2 (NITROGEN GAS) MAKES UP 78% OF THE ATMOSPHERE • N 2 IS HOWEVER LIMITED TO AMMONIA FOR MOST LIVING THINGS
NITROGEN FIXATION • CONVERSION OF N 2 TO AMMONIA • CERTAIN BACTERIA CAN CONVERT NH 3 = NITROGENFIXING BACTERIA • LIVE IN SOIL & IN SOME ROOTS
Recycling Nitrogen • BODIES OF DEAD ORGANISMS CONTAIN “N” – URINE & DUNG ALSO • DECOMPOSERS BREAK DOWN CORPSES & WASTE OF ORGANISMS GIVE OFF NITROGEN AS AMMONIA = AMMONIFICATION • NITRIFICATION = BACTERIA IN SOIL TAKE IN AMMONIA & OXIDIZE IT INTO NITRITES, NO 2 & NITRATES, NO 3 Back into the environment
DENITRIFICATION • RETURNING NITROGEN TO ATMOSPHERE • PLANTS CAN ABSORB NITRATES & AMMONIA FROM SOIL – ANIMALS CANNOT! • ANIMALS OBTAIN IT BY EATING OTHER ORGANISMS • THEY DIGEST THE PROTEINS & NUCLEIC ACIDS
COMPREHENSION QUESTIONS 1. WHAT IS THE BIOGEOCHEMICAL CYCLE 2. WHERE DO NITROGEN-FIXING BACTERIA LIVE? WHAT CRUCIAL FUNCTION DO THEY PERFORM? 3. DESCRIBE THE ROLE OF DECOMPOSERS IN NITROGEN CYCLE? 4. HOW HAS BURNING FOSSIL FUELS AFFECTED CARBON CYCLE? 5. THROUGH WHAT PROCESS DOES MOST H 20 VAPOR ENTER ATM.
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