Homework:•Complete Bioaccumulation w/s…Show your work•Be prepared for 35% nitrogen/carbon cycle mini-quiz next class period (study jams)•Nutrition/food retest Wednesday 4/29 am/pm/enrichment

Date Session Activity page

4/21-22 4 Food WebsEcological Pyramids

8

Classwork Quiz 9

4/23-24 5 Carbon Cycle 10

Nitrogen Cycle 11

Warm Up:Look at the warning label on your desk. Why are some types of fish included in the warningAnd others are not?

8.L.3 Understand how organisms interact with and respond to the biotic and abiotic components of their environment8.3.3 Explain how the flow of energy within food webs is interconnected with the cycling of matter (including water, nitrogen, carbon dioxide, and oxygen)

TLW complete quiz about population dynamics & food webs, then brainstorm Carbon and Nitrogen cycles, & recreate those cycles in play doh quizzes

• Bioaccumulation: Process where plants/animals take up a chemical from the environment and do not excrete it. The chemical builds up in the organisms over time to a potentially lethal level.

• Biomagnification: Higher concentrations of a chemical in organisms at higher levels in the food chain (at higher trophic levels.) As a result the chemical’s concentration is magnified from trophic level to trophic level.

• Available energy decreases as one moves up a food chain, concentration of toxins increases

Putting together what you already know•Energy is changed as it moves through a food web/chain.•Energy flows one way, no recycling•Matter is recycled as it moves through a food web.

The most common elements on earth are carbon, nitrogen, oxygen and hydrogen. These elements, along with water,

cycle between biotic and abiotic elements of the environment. This cycling is done through familiar

processes!

Carbon Cycle Diagram Carbon Cycle Notes

•Recreate the carbon cycle with clay•Use arrows and label the processes the arrows represent

Carbon Cycle Diagram Carbon Cycle Notes

Photosynthesis (plants):Move C from air to living organisms

Respiration (living things):C moved into atmosphere & oceans

Diffusion: atmosphere C oceans

Decomposition:Decomposers move C to soil, atmosphere & oceansIncomplete decay fossil fuel storage of C (coal/oil)

Combustion:Burning fossil fuels or other organic material moves C into atmosphere

OCEANS: CO2 used in sea shells, also ends up in sed. rock: limestone

Photosynthesis moves C from the atmosphere & oceans into living organismsCO2 + H2O C6H12O6 + O2

Respiration moves C from the living organisms into the atmosphere & oceans C6H12O6 + O2 CO2 + H2O

Decomposition

Decomposers move C to soil, atmosphere & oceans

Incomplete Decomposition

fossil fuel storage of C (coal/oil)

Carbon is also in the Oceans!!Animals in the ocean also pull carbon from water

(dissolved CO2) to use in their shells (CaCO3)

When they die, their shells are deposited at the bottom of the ocean. The shells become the

sedimentary rock: limestone.Oceans contain earth’s LARGEST store of carbon

Nitrogen Cycle diagram Nitrogen Cycle Notes

Nitrogen Cycle p11Nitrogen Cycle Notes

Nitrogen fixation : N2 in atmosphere is broken down and bonded with H or O (NH3/N2O)•Bacteria•Lightning•Industrial

Ammonification bacteria decompose plant and animal matter into (NH4)

Nitrification Bacteria convert NH3 NO3

Denitrification = bacteria convert NO3 N2

Nitrogen cycle4 processes

Nitrogen fixation : N2 in atmosphere are broken down and bonded with H or O (NH3/N2O)– Special Bacteria– Lightning– Industrial

Ammonification (Decay) = decomposing plant and animal matter into (NH4)

Nitrification = bacteria convert NH3 to NO3

Denitrification = bacteria convert NO3 into N2

Nitrogen Fixation•Special bacteria live in the soil or on root nodules of legumes(peas, beans, clover). They convert N2 to NH3. Now these special plants are able to use the nitrogen. This is a symbiotic relationship!

Nitrification

Different bacteria in soil can convert NH3 to NO3.

Other plants can now use

this form of Nitrogen.

Nitrogen Fixation• Energy from lightning breaks nitrogen molecules

apart, so they can combine with oxygen (N2O), then dissolve in rain to create (NO3), which is carried to the ground with the rain and deposited into the soil.

• Plants then absorb the nitrates and use them.

Nitrogen FixationIndustrial Production

Chemical reactions are used tochange the bonding of N2 to NH3

(fertilizer)

Ammonification Decomposition plant and animal matter into (NH4)

Denitrification

A third type of bacteria converts nitrates (NO3) to atmospheric nitrogen

(N2), which is returned to the air!

Human Impact carbonFossil Fuel naturally release carbon very slowly BURNING fossil fuels releases stored carbon very quickly. Burning anything (trees, oil, etc) releases CO2 into the atmosphere.

•CO2 gas dissolves in rain drops, making them more acidic…acid rain affects plants & aquatic life•Increasing CO2 in the atmosphere increases global warming. •As more CO2 dissolves into oceans, they become more acidic (ocean acidification) Limestone and SHELLS dissolve in acidic solutions.

Human Impact….nitrogenHuman activities have doubled the amount of fixed nitrogen entering the nitrogen cycle in the past 100 years

•Fertilizer runoff into surface water causes algae blooms…eutrophication (pond scum)•Fertilizer increases the rate of nitrification in the soil, increasing NOx to the air, which dissolves in rain drops and causes acid rain

Stop motion paper nitrogen cycle video

https://www.youtube.com/watch?v=6GLIzlUD-zw

Study videos

http://www.classzone.com/books/ml_science_share/vis_sim/em05_pg20_nitrogen/em05_pg20_nitrogen.swf

http://studyjams.scholastic.com/studyjams/jams/science/index.htm