NAME P ER LAB CELL ENERGY PTS CELLULAR R ... _____ PER_____ LAB A: CELL ENERGY (25 PTS) : CELLULAR RESPIRATION (INTERACTIVE DEMONSTRATION) - PART I BACKGROUND: All living cells, including the cells in your body and the cells in yeast, need ...

  • Published on
    30-May-2018

  • View
    309

  • Download
    11

Transcript

  • NAME _______________________________________________________ PER_____ LAB A: CELL ENERGY (25 PTS) : CELLULAR RESPIRATION (INTERACTIVE DEMONSTRATION) - PART I BACKGROUND:

    All living cells, including the cells in your body and the cells in yeast, need energy for cellular processes such as pumping molecules into or out of the cell or synthesizing needed molecules. ATP is a special molecule which provides energy in a form that cells can use for cellular processes. Yeast are tiny eukaryotic cells that produce CO2 or Carbon Dioxide as they convert glucose and oxygen to carbon dioxide and water during cellular respiration. Yeast produces gas by feeding on the sugars in flour, and expelling carbon dioxide in the process and that makes bread rise. Yeast is tiny: Just one gram holds about 25 billion cells. That amount of fungi can produce a significant amount of carbon dioxide, provided it has the simple sugars it uses as food. The three sugars that will be tested are glucose (blood sugar), sucrose (table sugar), fructose (fruit sugar).

    When the yeast respire aerobically ,oxygen gas is consumed at the same rate that CO2 is producedso there would be no change in the gas pressure in the flask, and the balloon would not inflate . However, when yeast ferments the sugars anaerobically, CO2 production will cause a change in the pressure of a closed flask, since no oxygen is being consumed, and the balloon will inflate.

    In this lab, you will also use Bromothymol blue as an indicator to show the whether CO2 is produced by the yeast cells as well as measure the amount of CO2 gas produced using latex balloons to trap the CO2.

    1. PURPOSE: __________________________________________________________________________________

    MATERIALS:

    Bakers yeast (4 g) Sugar Water Fruit Juice Sugar Substitute

    1 cup warm water (105 F) 3 large balloons Bromothymol Blue Solution Transfer pipettes (3)

    Label Tape Paper towels Flasks (3)

    PROCEDURES:

    1. Stretch out the balloon by blowing it up repeatedly, and then lay it aside. 2. Add yeast, *sugar and warm water into the flask and stir. 3. Youll notice the water bubbling as the yeast produces carbon dioxide. 4. Attach the balloon to the mouth of the flask, and set both aside. 5. Take your initial circumference measurement 6. Do not move the flask 7. Repeat this process for each type of sugar 8. After a few minutes, youll notice the balloon standing upright. If you dont see anything happen, keep

    waiting. Eventually, the balloon will inflate. 9. Use string to record the circumference of your balloon in 5 minute interval for 40 minutes

    Once you have completed the steps 1-8, 10. Remove the balloon from the flask (carefully, as liquid may be inside) 11. Use a transfer pipette to transfer 6mL of yeast solution into a test tube 12. Add 1mL of BTB (Bromothymol Blue indicator) to the tube 13. Observe noting color change 14. Continue to observe the color changes for up to 5 minutes 15. Smell the flask, note the smell.

    Bromothymol Blue Indicator Colors When the Bromothymol Indicator is BLUE it means When the Bromothymol Indicator is YELLOW it means When the Bromothymol Indicator is GREEN it means

    DATA Data Table 1: Growth of Balloon

    Time (min) Circumference (cm) Time (min) Circumference (cm) Glucose Fructose Splenda Glucose Fructose Splenda

    0 25 5 30 10 35 15 40 20

  • Graph: construct a graph showing the change in circumference over time. ***remember your TAILS!!!***

    1. EQUATION: Write out the equation for cellular respiration _________________________________________________________________________________________

    2. What is the independent variable? _________________________________________________________________________________________

    3. What is the dependent variable? _________________________________________________________________________________________

    4. What is the purpose of the indicator Bromothymol blue? _________________________________________________________________________________________

    5. List at least 3 things you know about yeast from previous labs? __________________________________________________________________________________________________________________________________________________________________________________

    6. What does the color change of the tube containing yeast represent? _________________________________________________________________________________________

    7. How do you know if the yeast produced CO2 and not some other gas that blew up the balloon? __________________________________________________________________________________________________________________________________________________________________________________

    8. What test did you do to verify it was CO2? ________________________________________________________________________________________

    9. What are the two types of Cellular Respiration ________________________________________________________________________________________

    10. Which type of cellular respiration one took place in this lab? ________________________________________________________________________________________

    11. How do you know? ________________________________________________________________________________________

    12. Describe the relationship between CO2 levels and pH levels __________________________________________________________________________________________________________________________________________________________________________________

    13. Do ALL CELLS GO through cellular respiration? _______________ Explain your answer! ________________________________________________________________________________________________________________________________________________________________________________________

  • Name__________________________________________________Date___________________Class____________ Photosynthesis Virtual Labs Tutorial:http://www.harcourtschool.com/activity/science_up_close/512/deploy/interface.html Watchandlistentothetutorialfoundinthelinkabove.Fillinthefollowinganswersasyouwatch.Stopandreplayanythingyoudontunderstandthisisacomplicatedtopic!

    1. Plantsusephotosynthesistomake__________________fortheplant.

    2. Whatdoplantsneedinordertoperformphotosynthesis?

    3. Howistheplantabletoobtaineachingredient?

    4. Identifytheplantcellorganelleinwhichphotosynthesistakesplace.________________________

    5. Summarizetheprocessofphotosynthesis.Waterandcarbonenterthechloroplast..__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    6. Whathappenstotheoxygenthatisproducedasaresultofphotosynthesis?

    7. Nameatleast2reasonswhyisphotosynthesisalsoimportantforpeopleandanimals?___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    VirtualLab#1http://www.reading.ac.uk/virtualexperiments/ves/preloaderphotosynthesisfull.html Bubblesaregivenoffbytheplantthroughphotosynthesis.Bymeasuringtherateatwhichthebubblesareproduceditispossibletotellhowfasttheplantisphotosynthesizing.Readandfollowthedirectionsonhowtousethislabsimulator.Pressstartandrecordthebubblesperminuteforeachofthefollowinglightdistances.GraphyourdataanddontforgetyourTAILS!

    LightDistance(cm)

    Bubblesper

    minute100

    120 150

    180 200

    8.Basedonyourdata,drawaconclusionregardinghowlightintensityaffectstherateofphotosynthesis.

  • VirtualLab#2http://www.kscience.co.uk/animations/photolab.swf Inthislab,youwillbeexperimentingwithhowdifferentvariablesaffecttherateofphotosynthesis.

    9. Setthethermometerto25C(RoomTemperature)andthelightintensityto20.a. Whatwerethebubblesperminuteatthissetting?______bpmb. NowincreasetheCO2availabletotheelodea.Whatwereyourbubblesperminute?______bpmc. Basedonyourdata,howdoestheamountofavailableCO2affecttherateofphotosynthesis?

    ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    10. Keepyoursettingsfrom9c(25C,lightintensityof20,increasedCO2).

    a. Whatwerethebubblesperminuteatthissetting?______bpmb. Nowincreasethetemperatureto40C.Whatwereyourbubblesperminute?______bpmc. Basedonyourdata,howdoesanincreaseintemperatureaffecttherateofphotosynthesis?

    ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    11. Returntoyoursettingsfrom9c(25C,lightintensityof20,increasedCO2).a. Whatwerethebubblesperminuteatthissetting?______bpmb. Nowdecreasethetemperatureto10C.Whatwereyourbubblesperminute?______bpmc. Basedonyourdata,howdoesadecreaseintemperatureaffecttherateofphotosynthesis?

    ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    12. Alterthevariablesinordertodeterminewhichcombinationleadstothehighestrateofphotosynthesis.Whichcombinationofsettingsproducedthehighestnumberofbubblesperminute?

    a. Temperature:________b. Light:________c. CO2:________

    PhotosynthesisTutorial:http://www.phschool.com/science/biology_place/biocoach/photosynth/overview.html Usethissitetoanswerquestionsaboutphotosynthesis.

    13. Writethechemicalequationforphotosynthesis.

    14. Photosynthesisconverts_________________energyintothe____________________energyofsugarsandotherorganiccompounds.

    15. Intheblankportionofthispaper,drawthepicturewhichshowstheoverallprocessofphotosynthesis

    Lab-Cell Energy SP2015Lab-photosynthesis-virtual-labsSP2015

Recommended

View more >