Date: May 5th, 2017
Aim # 73: How are molecules recycled through an
ecosystem?
Do Now: Take out the amoeba sisters worksheet from
yesterday and complete!
HW:
1)Daily Review of class notes
2)Castle Learning (QUIZ) due MONDAY
3)Test Corrections due TUESDAY
4)Test next Wednesday 5/11 (period 5), and
Thursday 5/12 (period 1)
Aim#73: How are molecules
recycled through an ecosystem?
Types of Cycles:
•Nitrogen
Cycle
•Water Cycle
•Carbon
Cycle
1) Material Cycles
•A cycle is something that repeats or
renews itself
•Self-sustaining ecosystems must recycle
materials between organisms and the
abiotic environment.
•C, H, O, N – molecules make up living
things and are recombined as they pass
through food webs
2) Water Cycle
Evaporation (release of
water from the surface
of things),
condensation (the
pulling together of
water molecules in the
atmosphere),
precipitation (rain),
transpiration
(evaporation of water
from plants)
Brain Pop: Water Cycle
https://www.brainpop.com/science/earthsystem/wa
tercycle/
Photosynthesis: CO2 + Light +H2O
Carbon Cycle
Respiration: O2 + Glucose
Glucose + O2
ATP + H2O +CO2
Carbon dioxide is used
& oxygen is released as
a result of
photosynthesis and
oxygen is used &
carbon dioxide is
released as a result of
cellular respiration.
Brain Pop: Carbon Cycle
https://www.brainpop.com/science/earthsystem/car
boncycle/
4) Nitrogen Cycle
•Remains of
dead organisms
are broken down
into compounds
plants can use
Ammonium = NH4+
Ammonia= NH3
Nitrate = NO3Nitrogen gas = N2
1) Nitrogen-Fixing Bacteria – Convert N2 to NH4+
2) Nitrifying Bacteria – Convert NH4+ to NO33) Decomposers – Return NH4+ to the soil
4) Plants use NH4+ & NO35) Denitrifying Bacteria – Convert NO3- to N2
Brain Pop: Nitrogen Cycle
https://www.brainpop.com/science/earthsystem/nit
rogencycle/
5) IS ENERGY EVER RECYCLED?
NEVER
Energy is transferred in the food chain from one
organism to the next. Some of the energy is changed to
kinetic energy (energy of movement) & some to heat
energy
6) Could life on earth exist without a
continues influx of solar energy?
No, Because it is the earth’s primary
source of energy & it can’t be recycled
Let’s Review
1) What do we call evaporation from the leaves of
plants?
2) What two process are involved in the carbon
cycle?
• Which one releases CO2?
• Which one uses CO2?
3) Which type of organisms play a critical role in the
nitrogen cycle?
4) What type of molecule is ammonium?
5) Can plants use atmospheric nitrogen?
6) Is energy ever recycled?