4.2 energy flow notes
- 1. 4.2 Energyflow 1 Essential idea:Ecosystemsrequire acontinuoussupplyof energytofuel life processesandto replace energylostasheat. 1. State the source of energyformostecosystems. 2. Outline the processof photosynthesis a. Give the chemical equationof photosynthesis. b. Give the wordequationof photosynthesis. c. State what formof energylightenergyisconvertedtoinphotosynthesis. 3. Define the following: Trophiclevel Predator Nature of Science:Use theoriestoexplainnatural phenomena—the conceptof energyflow explains the limitedlengthof foodchains.(2.2) 4.2 U1 Most ecosystemsrelyonasupplyof energyfromsunlight. 4.2 U2 Lightenergyisconvertedtochemical energyincarboncompoundsbyphotosynthesis. 4.2 U3 Chemical energyincarboncompoundsflowsthroughfoodchainsbymeans of feeding. 4.2 U4 Energyreleasedfromcarboncompoundsby respirationisusedinlivingorganismsand convertedtoheat. 4.2 U5 Livingorganismscannotconvertheatto otherformsof energy. 4.2 U6 Heat islostfrom ecosystems. 4.2 U7 Energylossesbetweentrophiclevelsrestrictthe lengthof foodchainsand the biomassof highertrophiclevels. 4.2 S1 Skill:Quantitative representationsof energyflow usingpyramidsof energy International Mindedness:The energeticsof foodchainsisa factor inthe efficiencyof food productionforthe alleviationof world hunger. Guidance:Pyramidsof numberandbiomassare not required.Studentsshouldbe clear thatbiomass interrestrial ecosystemsdiminisheswithenergyalongfood chainsdue tolossof carbon dioxide, waterand otherwaste products,suchas urea. From BiologySubject Guide, IBO, 2014
- 2. 4.2 Energyflow 2 Prey Producer Consumer 4. Describe whatismeantby a foodchain. 5. Suggesta reasonwhymostfoodchainsconsistof only3 – 5 organisms. 6. Constructa foodchainwith4 namedorganismsinit.State whethereachisa producer, primaryconsumer,secondaryconsumer,ortertiaryconsumer. 7. Outline whatthe arrowsina foodchain mean.
- 3. 4.2 Energyflow 3 8. Outline the processinwhichcellsconvertstoredchemical energyintoaformthat the cell can use. a. Name of the process. b. Chemical equationof the process. c. Energycurrencyof a cell. 9. Energyconversionssuchasthe one in#8 are never100% efficient.State the reasonwhy. 10. Explainhowenergylossesbetweentrophiclevelsrestrictsthe lengthof foodchainsandthe biomassof highertrophiclevels.(8marks) 11. Describe whata pyramidof energyshows.(Describemeanstogive adetailedaccountof) 12. State the unitsfor a pyramidof energy.
- 4. 4.2 Energyflow 4 13. Explainthe shape of a pyramidof energy. 14. Deduce the trophiclevel of a.ladybird b.berries c.rabbit d.frog e. fox View https://goo.gl/mjDuK9 15. Answerthe DBQ onp. 219.