Cell Respiration Lab

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Cell Respiration Lab
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Background Info

• Cell respiration allows the breakdown of glucose
  in the presence of oxygen to release energy.
  Carbon dioxide is released as a waste product in
  the process.
• Glucose can be acquired directly by plants
  through photosynthesis or directly by
  catabolizing other organic molecules such as
  carbohydrates, lipids or proteins.

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• Useful energy for cells is in the form of ATP, a
  common carrier of chemical energy in cells.
• Cellular respiration happens in 2 stages
  glycolysis and respiration ( Krebs and electron
  transport).
• If oxygen is present, Pyruvate is used to produce
  ATP through aerobic respiration which occurs in
  the mitochondria in eukaryotes and in the cell
  membrane in prokaryotes.

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Electron Transport

• Every NADH 3 ATP every FADH_at_ 2 ATP

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Electron transport oxygen is the last electron
acceptor!!!
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• If no oxygen is present,, Pyruvate is converted
  into either lactate or ethanol and carbon
  dioxide. This happens in the cytosol in a process
  known as fermentation.

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• The overall reaction for the breakdown of glucose
  into carbon dioxide and water releases 686
  kilocalories of energy! And can produce 36 to 38
  ATP molecules!

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• For this lab you should realize that oxygen gas
  and carbon dioxide gas are released and consumed
  at equal rates.
• KOH potassium hydroxide will react with carbon
  dioxide and form a solid potassium carbonate.
• CO2 2 KOH K2CO3 H2O

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• By getting rid of the carbon dioxide in this
  way, oxygen consumption during respiration can
  be measured with the respirometer or any other
  pressure gauge as a change in gas volume.

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PV n RT

• The pressure and volume will change
  proportionally to the number of molecules of gas
  present.
• If the number of gas molecules remains constant
  along with the temperature, the pressure will be
  inversely proportional to the volume. Pressure up
  volume down or volume up pressure down.
• IF you change the temperature and the number of
  molecules remains the same, then the pressure or
  volume or both will be proportional to the change
  in temperature. Temp up pressure and volume up!
• Gases and fluids flow from high to low pressure!

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• So if we keep the temperature and pressure
  constant, then the change in the volume of gas
  must be related to the amount of oxygen consumed
  by the organism and we can calculate a rate of
  respiration!

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Write Up

• Write the title
• Date
• A brief summary of why you are doing the lab.
• Write your basic outline of the procedure. What
  did you do to set up the lab?
• What are the safety concerns for the set up?
• What is the question you are looking to answer?
• What is your hypothesis? You may use the null.
• Prepare a data chart. If you prefer to have a
  neat one, make one on notebook paper and then
  transfer it to the lab book after you complete
  the lab.
• Record any observations that you make during the
  lab in the lab book.

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• As things happen that might be considered errors
  make note of them.
• This is a record of what you do, as you do it.
• Collect your data
• Analyze your data
• Get the class data
• Analyze the class data
• make a graph of the class data. Descriptive
  titles are necessary!
• Answer the analysis questions
• Form conclusions make sure you answer the
  original questions, use data to support any
  statement you make. How do you know the data is
  significant? Accept or reject your hypothesis.
  Include errors with reasons why they impact the
  results and how to correct them. What other
  extensions can be made to this lab?

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Video of lab

• http//www.cleanvideosearch.com/media/action/yt/wa
  tch?voL7C9_3biZQ

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Safety!

• Safety goggles KOH is corrosive!!! Do not get it
  on you skin! If you do, wash immediately with
  water for 15 minutes! You must wear goggles when
  handling the KOH!
• Lab aprons to protect your clothing!

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• Gather materials Day 1
• Set up lab station
• Put water in black containers so it can reach
  room temperature. Use a plastic jug to transport
  water to the container.
• Insert temperature probe.
• Set up respirometers. Check for leaks
• Measure volume of 10 germinating peas , record.
  save
• Measure equal volume of beads, record, save
• Practice reading the measurements on the
  pipettes.
• Test them for leaks before putting any seeds in
  them.
• Do a trial run with one that has beads in it.
• Put KOH in tubes today but not with the peas. Use
  the screw on lids to keep it from evaporating!
• Get everything ready!!!

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• Everyone will also do non-germinating peas
• Decide what other factor you want to change or
  test.
• this can be done at the same time as your
  original test to save time! Do 3 trials of yours
  if possible! Or get another group to do the same
  thing as you so you have more data!
• Make a data chart for your lab. Add a column for
  your new independent variable. ( so add 2 total)
• Readings are every 5 minutes for 30 minutes.
• Set up your original design plan and plan to run
  it simultaneously, for example, if you can set
  up a third tube with a different type of seed in
  it or set up an second water bath at a different
  temperature. With light, ice, heat.

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• Since respiration uses oxygen, the water will be
  pulled into the tube as oxygen is consumed moving
  the water closer towards the glass cylinders.
  Read the start position at time zero and then
  each 5 minutes read the new position to get the
  amount of oxygen consumed. Make sure you can read
  the start and finish volume on the pipette

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Corrected differences

• To correct for changes not due to respiration,
  the tube with beads is used. Subtract any change
  that occurs in this tube from the change that
  occurs in the tube that has germinating seeds to
  show the true movement that is not due to the
  temperature or pressure changes in the set up.

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Germinating peas Germinating peas Germinating peas Non-Germinating Peas Non-Germinating Peas Non-Germinating Peas Your independent variable Your independent variable Your independent variable Acrylic beads Acrylic beads
Temp C Time min Volume (ml) dif Corr dif Volume (ml) dif Corr dif Volume (ml) dif Corr dif Volume (ml) dif
0
5
10
15
20
25
30
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Class data

• Place your group data for corrected difference
  for germinating peas, non-germinating peas and
  difference for beads on the data chart.
• We will calculate a class average to use for the
  final data analysis and conclusion.
• This will be like repeating the lab 6 times!

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Germinating peas Corrected differences by groups Germinating peas Corrected differences by groups Germinating peas Corrected differences by groups Germinating peas Corrected differences by groups Germinating peas Corrected differences by groups Germinating peas Corrected differences by groups Class average
Temp C Time min 1 2 3 4 5 6
0
5 .5 .4 .1 .3 .4
10 .8 1.0 .4 1.0 .7
15 1.2 1.2 1.0 1.7 1.2
20 1.6 2.0 1.5 2.4 2.1
25 1.9 2.5 1.9 3.1 3.3
30 2.2 3.2 2.3 3.7 3.8
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Non Germinating peas Corrected differences by groups Non Germinating peas Corrected differences by groups Non Germinating peas Corrected differences by groups Non Germinating peas Corrected differences by groups Non Germinating peas Corrected differences by groups Non Germinating peas Corrected differences by groups Class average
Temp C Time min 1 2 3 4 5 6
0 - - - - -
5 0 -.02 0 0.2 0
10 .1 -.02 0 0.3 -0.1
15 .1 -0.6 0.7 0.4 0
20 .1 -0.3 0.7 0.9 0
25 .1 -0.5 0.6 0.5 0
30 .1 -0.5 0.7 0.5 0
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Beads differences by groups Beads differences by groups Beads differences by groups Beads differences by groups Beads differences by groups Beads differences by groups Class average
Temp C Time min 1 2 3 4 5 6
0 - - - - -
5 0 0.6 0.4 0 0
10 0 0.8 0.4 0 0.1
15 .1 0.6 0.4 -0.1 0.1
20 .1 0.4 0.4 -0.1 0.1
25 .1 0.6 0.5 -0.2 -0.2
30 .1 0.8 0.5 -0.2 -0.2
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Independent variables by groups Kidney beans Independent variables by groups Kidney beans Independent variables by groups Kidney beans Independent variables by groups Kidney beans Independent variables by groups Kidney beans Independent variables by groups Kidney beans Class average
Temp C Time min 1 2 3 4 5 6
0 - -
5 .3 0.4
10 .6 0.7
15 .8 1.2
20 1.6 1.7
25 1.7 2.2
30 1.9 2.5
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Independent variables by groups Temperature change Independent variables by groups Temperature change Independent variables by groups Temperature change Independent variables by groups Temperature change Independent variables by groups Temperature change Independent variables by groups Temperature change Class average Average Temperature change
Temp C Time min 1 7.7 C 2 8 C 3 4 5 6 Average temp 7.9 C
0 - -
5 0.4 0.4
10 0.5 1.0
15 1.7 1.4
20 2.3 0.9
25 2.5 -1.3
30 2.8 -1.8
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Graph the class averages for corrected
differences for germinated peas, non germinating
peas and your other independent variable
Include a descriptive title! This means it
includes what is on each axis, treatments and the
key information
Average ml of oxygen consumed
Key Germinating peas Non germinating
peas Beads Temperature and kidney beans
(germinating)
Time (0 -30) minutes
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Analysis

• 1.   State a hypothesis that relates to
  temperature that is being tested by this lab
  exercise.
•  
• 2.   State a hypothesis that relates to the state
  of seed germination that is being tested by this
  lab exercise.
•  
• 3.  Calculate the RATE of oxygen consumption for
  the germinating seeds at room temperature water. 
  Rate can be calculated by determining the SLOPE
  of the line from your graph.
•  
• 4.  In this lab exercise, what is the purpose of
  the .
•  Beads KOH
• Respirometer
•  
• 5.  Explain why the water moved within the
  pipette.

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Conclusion

• Use the rubric given and write a conclusion.

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Write Up

• Write the title
• Date
• A brief summary of why you are doing the lab.
• Write your basic outline of the procedure. What
  did you do to set up the lab?
• What are the safety concerns for the set up?
• What is the question you are looking to answer?
• What is your hypothesis? You may use the null.
• Prepare a data chart. If you prefer to have a
  neat one, make one on notebook paper and then
  transfer it to the lab book after you complete
  the lab.
• Record any observations that you make during the
  lab in the lab book.

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• As things happen that might be considered errors
  make note of them.
• This is a record of what you do, as you do it.
• Collect your data
• Analyze your data
• Get the class data
• Analyze the class data
• make a graph of the class data. Descriptive
  titles are necessary!
• Answer the analysis questions
• Form conclusions make sure you answer the
  original questions, use data to support any
  statement you make. How do you know the data is
  significant? Accept or reject your hypothesis.
  Include errors with reasons why they impact the
  results and how to correct them. What other
  extensions can be made to this lab?