Transcript Energy-FLow-and-Cycles1516 rev1

Check Yer Head 
Thoroughly explain the following ecological terms
using complete sentences. If you can do it…your
golden!

Community
2. Population
3. Biosphere
4. Organism
5. Ecosystem
6. Ecology
1.
Energy Flow and Cycles




1.
2.
3.
An ECOSYSTEM is…all of the living
(BIOTIC) AND non-living (ABIOTIC)
things within an area…you know this.
Energy moves through an ecosystem.
An organism’s ENERGY ROLE is part of
its NICHE.
The ENERGY role can be that of a:
PRODUCER
CONSUMER
DECOMPOSER
PRODUCERS





SUNLIGHT is the primary energy source for
ecosystems.
Autotrophs (organisms that make their own
food) are the primary producers for almost all
ecosystems.
Photosynthetic autotrophs are the predominant
type of autotroph and they use the sun to make
food.
Remember…6CO2 + 6H2O 6O2 + C6H12O6
Producers are food for…CONSUMERS
CONSUMERS






Consumers get energy by feeding upon
other organisms.
These are HETEROTROPHS…they can’t
make their own food.
Three Main Types:
HERBIVORES: eat plant materials
CARNIVORES: eat other animals…some
eat dead stuff…these are SCAVENGERS
OMNIVORES: eat all types of things
DECOMPOSERS



These are organisms that break down
waste and the remains of dead organisms.
Decomposers return the raw organic
materials to the soil where it is recycled
back into the ecosystem.
Bacteria and Fungi are two main groups of
decomposers.




FOOD CHAINS: show how energy moves
through an ecosystem by showing what is
eating what.
FOOD WEBS: are made up of many food
chains.
ENERGY PYRAMIDS: show how much
energy is moving from one level to the
next in a food web.
Only about 10% of the energy at one level
of a food web is transferred to the next
highest level.

Because there is so much energy lost from
one level to the next…the top of the food
web or energy pyramid has fewer
organisms.
A Typical Food Chain
A Typical Food Web
Comprised of several food chains
A Typical Energy Pyramid
How the numbers work in an
Energy Pyramid
Try These…
1.
2.
3.
4.
Pick an ecosystem (any one you want), and list
as many abiotic and biotic factors as you can.
Draw a food web within that ecosystem that
includes at least four trophic levels and six
different organisms. Label the levels and
energy roles of each organism.
If there is 10,000kcal of energy available at the
producer level, how many kcal would be
available to an apex predator?
Remove one organism from your food web and
explain the effect that this would have on the
rest of the organisms.
CYCLES

1.

There are some major cycles that are
important for biologists to understand.
WATER CYCLE: a continuous process
wherein water moves from the Earth’s
surface to the atmosphere and back.
There are four basic part to this cycle.
1. WATER CYCLE
1. WATER CYCLE




EVAPORATION: LIQUID water absorbs energy
(heats up) and turns into a GAS (Surface to
atmos.).
CONDENSATION: Water vapor (GAS) in the
atmosphere looses energy (cools) and turns into
a liquid (clouds).
PRECIPITATION: occurs when droplets of water
that are formed during condensation get bigger
and fall back to Earth.
Transpiration: water is absorbed by plants and
subsequently released back into the atmosphere through
their leaves.
2. CARBON (CO2) CYCLE
2. CARBON (CO2) CYCLE
PHOTOSYNTHESIS & CELLULAR
RESPIRATION
 Producers take in carbon from CO2 and
produce oxygen, while consumers take in
the oxygen and give off CO2.
 Photosynthesis (in the chloroplasts):
6CO2 + 6H2O Sunlight6O2 + C6H12O6
 Cellular Respiration (in the mitochondria):
6O2 + C6H12O6 6CO2 + 6H2O + ATP (Energy)

The Essence!
Carbon is cycled (converted) from
Inorganic Carbon is to Organic
Carbon…and the other way around.
Photosynthesis:
Plants make FOOD from ENERGY
Cellular Respiration:
Organisms make ENERGY from FOOD.
The NITROGEN CYCLE
The NITROGEN CYCLE



Nitrogen is another important element for
living things.
Most organisms cannot get it directly from
the atmosphere.
Nitrogen by itself in the atmosphere is
called FREE nitrogen. Nitrogen that is
attached to other elements is called FIXED
nitrogen…that’s the kind we need.







Organisms require nitrogen-compounds,
(proteins and nucleic acids).
Air is about 78% nitrogen gas (N2). That’s
where most of the nitrogen hangs out.
Most organisms can’t use atmospheric
(free) nitrogen as is. They need it
changed into nitrogen compounds.
Plants need their nitrogen "fixed", which means
as part of compounds such as:
ammonia (NH3)
urea (NH2)2CO
nitrate ions (NO3−)
NITROGEN FIXATION





This is the process that changes free nitrogen
into the usable fixed kind.
Bacteria in the soil, plant root nodules, and in
water change the nitrogen into compounds
called nitrites /NO2- (nitrosomonas) and then to
nitrates /NO3-(nitrobacter).
These can be used by the plants to make
proteins and other needed compounds.
Animals eat the plants…other animals eat those
animals, and the nitrogen gets used by them
too.
Lightning and industrial processes also fix free
nitrogen.


When an organism dies, the nitrogen
compounds return to the ecosystem and
are reused.
Eventually they are broken down
completely (denitrification) and return to
the atmosphere…and the cycle begins
again…that’s why its called a cycle!
FYI…if you’re gonna take
biology in college…
There are four sub-processes involved in
the Nitrogen Cycle. You don’t have to
know this now, but…someday…
1. Nitrogen Fixation: breaks N apart so it can form compounds.
2. Decay: waste from life processes (ammonification).
3. Nitrification: bacteria converting ammonia to

2
nitrites and then to nitrates (which what plants can
assimilate).
4.
Denitrification:
nitrogen gas again.
bacteria converting nitrates to
4. The Phosphorus Cycle
4. The Phosphorus Cycle
Phosphorus is a super-important element
that is a key part of ATP, DNA molecules
(more on DNA later…a lot more!), bone,
shells…n’ other stuff too.
Ya know how NITROGEN is from the
atmosphere? Of course you do…we just
talked about it. Well…Phosphorous (most of
it) is in the Earth’s soil and rocks in
compounds called phosphates (PO43-).




Most Phosphorus is stored in the crust as the
mineral Apatite aka…Calcium Phosphate aka
Ca5(PO4)3
The extrusive igneous rock…granite, is where
you can find apatite, but it is also found in
metamorphic and sedimentary rocks too.
Some Phosphorus is dissolved in fresh and
ocean water, or is stored in soil or in organic
matter.
Plants can take phosphates from the soil
sorta like they do with NITROGEN. No
special bacteria for this one.

Too much phosphate (or nitrogen) ain’t a
good thing and can lead to problems such
as lake eutrophication (nutrient buildup)
leading to algal and bacterial blooms.
These guys use up the oxygen and
BLAMMO!…dead fish everywhere! NOT
COOL