3.4 Workbook Review

*Vocab*Key Questions (at top of wkbk)

*What is important about each cycle?

Recycling in the Biosphere

• 1. The four elements that make up over 95% of the body in most organisms are oxygen, sulfur, nitrogen and hydrogen

• False – CARBON• 2. Matter moves through an ecosystem in cycles• True• 3. Chemical and physical processes include the

formation of clouds and precipitation, “burning food”, and the flow of running water

• False - LIGHTNING

• 4. The illustration draws an analogy between the way energy drives matter to cycle in an ecosystem and the way water causes a waterwheel to turn. Give an example of another analogy that could be used to show the relationship between energy and the cycles of matter.

• Ex: wind causing windmill to turn; car engine causing wheels to turn; foot pushing bicycle pedal around and around…

• 5. Explain why Earth is considered a closed system• Matter does not enter or escape the earth. They are

recycled through organisms.• 6. How might building a new highway affect the cycles of

matter?• Building a highway means clearing out trees, plants,

and habitats of organisms, which limits nutrient availability. This prevents the nutrients from being recycled

THE WATER CYCLE:• 7. What role do plants play in the water cycle?• Absorb groundwater through roots• *Transpiration - plants lose water through leaves

(evaporation through tiny pores)

• 8. Draw a diagram explaining the water cycle. LABEL the processes involved as biological or physical/chemical

• 9. Complete the chart about the carbon cyclePROCESSES THAT CAUSE CARBON TO MOVE INTO THE ATMOSPHERE

PROCESSES THAT CAUSE CARBON TO MOVE OUT OF THE ATMOSPHERE

PROCESS DESCRIPTION PROCESS DESCRIPTION

Respiration Photosynthesis

Release of CO2 and other gases into the atmosphere through vents in Earth’s crust

Organisms eat and break down food, releasing CO2 through cellular respiration

Volcanic Activity

Plants use of sunlight and CO2 to produce carbohydrates

Ex: Dissolving, fossil fuels, others?

CO2 dissolves in rainwater; animals are decomposed, pressurized and converted to fossil fuels over time

• 10. The carbon in coal, oil, and natural gas came fromA. combustion of fossil fuelsB. remains of dead organismsC. carbon-fixing bacteria in swamp soilD. carbon dioxide dissolved in ocean water

• B. remains of dead organisms• 11. How does most of the carbon in an organism’s body return to the

environment after the organism dies?A. decomposers break down into simpler compoundsB. heat from the sun causes carbon in the body to evaporateC. geological processes cause it to turn into fossil fuelD. rainwater dissolves carbon in body and carries to the ocean

• A. decomposers break down into simpler compounds• 12. Human processes mainly contribute to

A. release of carbon dioxide (CO2) into the atmosphereB. decrease of total amount of carbon found on earthC. depletion of carbon dioxide reserves in atmosphereD. increase in carbon contained in rock material

• A. release of carbon dioxide (CO2) into the atmosphere

13 – 16 about Nitrogen Cycle!•13. Nitrogen in the form of ammonia, nitrate, and nitrite is found in the soil•True•14. Nitrogen fixation is the process in which certain bacteria convert nitrogen gas into nitrates•False- Ammonia•15. Denitrification is the process by which some soil bacteria convert nitrates into nitrogen gas•TRUE•16. All organisms require nitrogen to make amino acids, which in turn are used to build carbohydrates•False – proteins

17 – 21 about Phosphorus cycle!•17. Phosphate is released as rocks and sediment wear down•True•18. Plants absorb phosphate from the soil or water.•True•19. Phosphorus is the most abundant gas in the atmosphere•False – nitrogen (about 75%!! More than oxygen…)•20. Organic phosphate is taken up by producers during photosynthesis and released by cellular respiration•False – carbon dioxide•21. Phosphorus forms part of the important life-sustaining molecules such as DNA and RNA•True (So does nitrogen…)•22. Plants absorb phosphorus from the atmosphere or water•False - soil

• 23. List and describe the biological steps in the nitrogen cycle• *Nitrogen fixation – bacteria take nitrogen gas from

atmosphere and fix (make it stick) it into soil• Once in soil, plants absorb it into their roots• Consumers eat producers and reuse the nitrogen to make

compounds• Decomposers release nitrogen from dead organisms into soil• Bacteria convert it back to a gas - *denitrification

• 24. What is atmospheric nitrogen fixation, and how does it affect organisms

• When lightning strikes, some atmospheric nitrogen is converted to usable compounds in soil to be used by organisms (wow!)

• 25. How do humans add nitrogen to the biosphere?• Fertilizers!! (good or bad…)• 26. Which parts of the phosphorus cycle are

geological processes?• Geological activity- marine sediment turned into

rock and washes phosphates from rock to ocean

• 27. The visual analogy compares interlocking gears to the major nutrients – potassium, phosphorus, and nitrogen. What other “gears” would be affected if these stopped working?

• Plants and organisms could be added to the analogy• Plants cannot live without these vital nutrients, thus…• Consumers would not have oxygen produced by plants• Consumers would not get their food sources

• 28. If a nutrient were in short supply in an ecosystem, how might it affect an organism?

• Limit organism’s growth, or even survival• 29. When is a substance a limiting nutrient?• When it is scarce or cycles very slowly and limits an

ecosystem’s growth• 30. Compare and contrast the flow of energy through an

environment with the flow of matter through that same environment

• Matter moves differently than energy. • Energy is captured by producers and passes from one

trophic level to the next, and some energy is lost at each step.

• Matter is recycled within and between ecosystems. Elements pass from one organism to another and through nonliving things in the environment – these loops are called **biogeochemical cycles

• The End! Whew!• Focus on your vocabulary terms, and the “key questions”

found at the beginning of the workbook