1. Review From Last class: Answer questions in TOTD Folder
Your house is an example of a(n) ___.
a. biotic factor b. habitat c. niche
Trees, mosses and shrubs are all examples of what type of factor?
a. abiotic b. biotic c. commensalism
The study of interactions between organisms and their environments is called ?
a. botany b. cytology c. ecology
If you work at McDonald’s, that is an example of your?
a. habitat b. niche c. community
A group of deer that live in a forest is an example of a?
a. biosphere b. community c. population

2. IN 29 & 31 Headings Vocabulary Important Info
Ecosystem Recycling
IN 29 & 31
Headings
Vocabulary
Important Info

3. 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

4. Water Cycle CELLS CONTAIN 70-90% H20
VERY LITTLE OF EARTHS AVAILABLE H20 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 H20 B/T RESERVOIRS
EVAPORATION
TRANSPIRATION
PRECIPITATION

5. Evaporation ADDS H20 VAPOR TO ATMOSPHERE
HEAT CAUSES WATER TO EVAPORATE
90% OF EVAPORATED WATER FROM TERRESTRIAL ECOSYSTEM PASSES THROUGH PLANTS IN A PROCESS CALLED…

6. Transpiration PLANTS TAKE IN H20 THRU ROOTS
RELEASE WATER & TAKE IN CO2 (CARBON DIOXIDE)
ANIMALS DRINK/ EAT TO TAKE IN H20
ANIMALS RELEASE IT WHEN:
BREATHING
SWEATING
EXCRETION

7. 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

8. Carbon Cycle PHOTOSYNTHESIS + CELLULAR RESPIRATION
PHOTOSYNTHESIS = PLANTS & OTHER AUTOTROPHS USE:
CO2 + H20 & SUNLIGHT = CARBOHYDRATES

9. CELLULAR RESPIRATION
PROCESS IN WHICH AUTOTROPHS & HETEROTROPHS USE OXYGEN (O2) TO BREAKDOWN CARBS.
CELLS MAKE ATP (ENERGY) BY BREAKING DOWN ORGANIC COMPOUNDS
A COMPOUND THAT RESULTS FROM LIVING THINGS & CONTAINS CARBON

10. HUMAN INFLUENCE ON THE CARBON CYCLE
IN THE PAST 150 YEARS CO2 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

11. BURNING RELEASES ENERGY & CO2
BURNING VEGETATION RELEASES CO2
TROPICAL RAINFOREST DESTRUCTION
WITH NO PLANTS CO2 IS NOT ABSORBED

12. Nitrogen Cycle NITROGEN IS NEEDED TO MAKE PROTEINS & NUCLEIC ACIDS:
ORGANIC MOLECULE, DNA OR RNA, THAT STORES & CARRIES IMPORTANT INFO FOR CELL FUNCTION
N2 (NITROGEN GAS) MAKES UP 78% OF THE ATMOSPHERE
N2 IS HOWEVER LIMITED TO AMMONIA FOR MOST LIVING THINGS

13. NITROGEN FIXATION CONVERSION OF N2 TO AMMONIA
CERTAIN BACTERIA CAN CONVERT  NH3 = NITROGEN- FIXING BACTERIA
LIVE IN SOIL & IN SOME ROOTS

14. 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, NO2 & NITRATES, NO3
Back into the environment

15. 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

16. 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 H20 VAPOR ENTER ATM.