Cellular

Respiration ILS

Unit 6

Semester 2

Name ____________________________

Teacher _______________Hour _____

ATP—LIKE A RECHARGEABLE BATTERY

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THE EVOLUION OF OBTAINING ENERGY

Imagine the earth 4.6 billion years ago. Its atmosphere contained no oxygen at all. The atmosphere was made of carbon dioxide, nitrogen, water vapor, and hydrogen dioxide, but no oxygen. Nevertheless, organisms eventually evolved to live in this unpleasant environment. The first organisms were single celled organisms, much like the prokaryotes of today. These bacteria got their energy from the sun. They made glucose that they would eventually change and use for fuel. The early atmosphere was lacking in what important gas? _________________

Recall that we cannot immediately use the energy from the food that we eat. It needs to be broken down into monomers by your digestive system. In the case of carbohydrates, they are broken down into monomers such as glucose. The glucose then cruises through your blood stream and is eventually taken up by your cells through facilitated diffusion. However, just like the early bacteria, the glucose is still not in a form the cell can use directly for energy. What is the carbohydrate monomer that a cell can change into fuel? ________________

ATP is the molecule that a cell can actually use for energy to do work. So, it is not surprising that the early bacteria evolved a way to convert the energy in glucose to ATP. For every glucose molecule it had, the bacteria were able to produce 2 ATP molecules. Because there was no oxygen in the atmosphere, they were going through a process called anaerobic respiration. What is the molecule called that cells can actually use as fuel? _________ The process of changing glucose into ATP without oxygen is called: ___________________ _________________.

Glucose

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For over a billion years these early bacteria were the dominant life form. So, where did the oxygen that is so important to us today come from? Strangely enough, it was a waste product that the bacteria produced. When they initially made their glucose from sunlight, oxygen was made as a waste product. Plants and some bacteria still do this today during photosynthesis. What process produces oxygen in the atmosphere? ________________

Eventually, the oxygen built up so much that a different way of changing glucose into ATP evolved. Cells began using oxygen in a process called aerobic respiration to change glucose into ATP. Amazingly, this process produced 36 ATP instead of the measly 2 ATP produced during anaerobic respiration. Because of this surplus of energy cells were able to grow larger and more complex. The process of changing glucose into ATP using oxygen is called: ___________________ _________________. These complex cells, called eukaryotic cells, appeared about 2 billion years ago. They are the ancestors of most algae, fungi, plants, and animals. These are complex organisms with energy needs that only aerobic respiration provides. Without the marvelous process of aerobic respiration, early bacteria might still be Earth’s dominant life form. No matter which way you do it, this whole process of producing ATP from glucose is called CELLULAR RESPIRATION.

In the space below, write a summary statement about this reading.

Eukaryotic cell

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ILS—Laboratory—Cellular Respiration of Yeast

Purpose: To observe how added sugar (a food source) affects the cellular respiration of yeast.

Materials: Yeast, eudiometer tube, ring stand, spatula, water bath, sugar, electronic balance (one that goes to 0.00), 100 ml graduated cylinders, 250 ml flasks with stopper and hose, thermometers

Procedure: (Draw the apparatus in the space provided)

1. Set up the eudiometer tube as demonstrated by your teacher.

2. Measure out 25 ml of warm tap water (35 ºC) in a graduated cylinder.

3. Add the water to your flask and then measure out your specified amount of sugar.

4. Add the sugar to the flask and gently mix for about 1 minute until sugar is fully dissolved.

5. Weigh 1g of yeast. Add the yeast to the flask and swirl gently until the yeast is fully dissolved.

6. Make sure the hose on the stopper is inserted into the eudiometer tube and then place the stopper in

the flask.

7. Start timing and record the CO2 output from the yeast every 3 minutes for up to 12 minutes.

8. Record your data on the class data table on the board and graph the amount of sugar vs. CO2

output at a particular time (such as 10 minutes).

NOTE: You may want to set up 0 grams of sugar as a control for the whole class and not assign

this amount to a student group.

Microscopic Microscopic Microscopic Microscopic

Yeast CellsYeast CellsYeast CellsYeast Cells

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Data Table:

Sugar in grams 3 minutes 6 minutes 9 minutes 12 minutes

0 g

0.1 g

0.2 g

0.3 g

0.4 g

If there is more than one group recording data for the same sugar amount, average their results and record them in the table above.

Analysis/Discussion:

1) Explain (in terms of cellular respiration) why you think the results of the lab look the way they

do.

2) Why does sugar affect the cellular respiration of yeast?

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Title:

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Using Graphs and Tables to Interpret Data – Cellular Respiration Since spring is upon us, it’s time to start thinking about green plants starting to grow…yippee! You know that growing, whether a human or a plant, takes a great deal of energy. You also know (from our introductory reading) that the process of changing glucose into usable energy (for things like growth) requires the use of oxygen. Ms. Frontier, Mr. Olsen, and Mr Sharpe, being the crazy science teachers that they are, decide to do an experiment. They want to know how temperature affects the amount of oxygen that is consumed by a specific type of corn plant to use in cellular respiration.

The graph below shows a comparison between four corn plants of the same species. Two plants are germinating, meaning that the corn plant is beginning to sprout from its seed and grow out of the ground. The other two plants are not germinating, and thus, have not broken from the seed.

O2 Consumption at Various Times and Temperatures in One Variety of Corn Use the graph to answer the following questions.

1. What is the independent and dependent variables for this experiment?

A. Independent Variable(s): __________________________________________ B. Dependent Variable(s): ___________________________________________

2. In this experiment, oxygen consumption is measured in __(units)__? ___________________________

3. Oxygen consumption is measured in ________ minute intervals?

4. Oxygen consumption in corn was measured at two different temperatures. These temperatures were:

__________ and __________ degrees Celsius.

5. Approximately how many milliliters of O2 were consumed by the germinating corn seed (22°C) at 15 minutes?

6. Approximately how many milliliters of O2 were consumed by the non-germinating corn seed (22°C) at 15 minutes?

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_____ 7. Which concluding statement BEST describes the overall trend in the data? A. These corn plants consume more oxygen in colder temperatures than in warmer temperatures. B. Every five minutes, corn plants consume two times more oxygen than they did in the five minutes

prior.

C. Germinating and Non-germinating corn plants at 22°C consume two-times as much oxygen as their

counterparts consume at 12°C. D. Corn likes warmer temperatures.

8. Why did you choose that answer for the previous question? Explain your reasoning. YOU MUST REFER TO DATA

FROM THE GRAPH IN YOUR EXPLANATION!

_____ 9. Four different students were asked to make a statement about the data in the table. Choose the CORRECT statement or statements.

A. All corn plants at 12°C consume less oxygen than their counterpart plant at 22°C.

B. Germinating corn at 22°C consumes six-times as much oxygen as non-germinating corn at 22°C.

C. Non-germinating corn at 22°C consumes more oxygen than germinating corn at 12°C.

D. Overall, germinating corn at 22°C consumes more oxygen than non-germinating corn at 12°C. _____ 10. Which combination of variables (temperature and germination/non-germination) will result in greatest amount of

oxygen consumption in corn plants?

A. 12°C / non-germinating

B. 22°C / non-germinating

C. 12°C / germinating

D. 22°C / germinating

_____ 11. If you had to predict approximately how much oxygen would be consumed by a germinating corn plant (12°C) at 25 minutes, you would say:

A. approximately 2.0 ml B. approximately 1.2 ml C. approximately 1.0 ml D. approximately 0.5 ml

12. Ms. Frontier, Mr. Olsen, and Mr. Sharpe are so excited about their findings that they decide to do another experiment.

They will use two corn plants at two different temperatures (12°C and 22°C) to answer the question:

Does the amount of oxygen consumption (of a corn plant) at two different temperatures affect the amount of CO2 produced during cellular respiration?

Please write a hypothesis for this test:

_________________________________________________________________________________________________

_________________________________________________________________________________________________

What is your reasoning for your hypothesis? (Do not say that you ‘just guessed’…there is a reason!)

_________________________________________________________________________________________________

_________________________________________________________________________________________________

_________________________________________________________________________________________________

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Directions: Turn to p. 360 in the BSCS Biology: A Human Approach textbook. Begin reading the section titled “Energy for Cellular Activity”. As you read, fill in the guided notes below.

A. ATP– A T P

1. Purpose: 2. Function:

3. Energy in ATP comes from __________________________________________. 4. Drawings:

a) Structure of ATP:

b) Conversion of ATP to ADP in a reaction that releases energy:

5. Law of Conservation of Energy: You may now skip ahead to page 362, and begin reading the section titled “Controlling the Release of Energy from Matter: An Overview of Cellular Respiration.”

B. Cellular Respiration Overview: 1. Definition:

2. Overall equation for cellular respiration:

C6H1206 + 6O2 ⇒ 6CO2 + 6H20 + ATP

3.

3 Stages: Location in cell How much ATP?

a. Glycolysis Cytoplasm Some

b.

c.

W

Glucose

Cellular Respiration Notes

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C. Cellular Respiration: A Closer Look

1. 1st stage: Glycolysis

a. What is used in this stage?

b. What is produced in this stage?

i.

ii.

c.

d. Drawing of glycolysis: e. Other (to be filled in during teacher-led discussion tomorrow)

NET ATP PRODUCED FROM GLYCOLYSIS = ____

http://www.anselm.edu/homepage/jpitocch/genbio/glycolysis.JPG

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2. 2nd Stage: The Kreb’s Cycle:

a. Because the Kreb’s Cycle requires ___________ , it is called aerobic respiration. b. What goes into the Kreb’s Cycle?

c. What is produced in the Kreb’s Cycle? i. ______, which is exhaled through the lungs

ii.

iii.

d.

*** Keep in mind that glycolysis produces 2 pyruvate molecules, which each

go through the Kreb’s Cycle

d. Drawing of the Kreb’s cycle: e. Other (to be filled in during teacher-led discussion tomorrow)

NET ATP PRODUCED FROM KREB’S CYCLE = _____

http://www.sp.uconn.edu/~bi107vc/images/mol/krebs_cycle.gif

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3. 3rd Stage: The Electron Transport System:

a. The Electron Transport System is (anaerobic / aerobic) (circle one)

b. What molecule, produced in glycolysis and the Kreb’s Cycle, goes into the Electron Transport system?

c. List of the major steps of the electron transport system: (summarize the steps described in the textbook below as best as you can… your teacher will help you with these tomorrow)

d. . d. Drawing of electron transport system:

*NET ATP PRODUCED FROM ELECTRON TRANSPORT SYSTEM = 32!!!

*TOTAL ATP PRODUCED IN ALL 3 STAGES OF CELLULAR RESPIRATION = _______

e-

e-

Electron Transport System

H+

H+

H+

H+

H+

H+

H+

H+

H+

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D. Regulation and Energy Production: Read pages 367 – 369 in the text.

1. Drawing:

2. What by-products form when no oxygen is available?

a. In animals:

b. In yeast/bacteria:

http://fig.cox.miami.edu/~cmallery/150/phts/atpase.jpg

http://www.nicerweb.com/doc/class/bio1151/Locked/media/ch09/09_19Catabolism.jpg

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E. Overview of the three processes:

Aerobic Cellular Respiration Rap

C6H12O6 and 6O2 will fix the mix

Then 6 CO2 from out of the blue

And 6 H2O there ain’t much mo(re)

Just the ATP, that’s the energy for you and me

Word…

Full equation for aerobic cellular respiration: C6H12O6 + 6 O2 6 CO2 + 6 H2O + 36 ATP

http://faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20101/Bio%20101%20Lectures/cellular%20respiration/cellul15.gif

Aerobic respiration

Anaerobic respiration

is utilized by

begins with

Cellular Respiration

Literally

means

produces a net of

which produces 2

Breaks down

Into 2

can be

used in

that produces

that requires

occurs in the

produces a net of

produces

produces

that transports

to the

occurs in the

series of that pump

Across the

membrane of

down the

through

WORD BANK

all living things

ATP

ATP synthase

CO2

concentration gradient

cytoplasm

Electron Transport Chain (ETC)

glucose

glycolysis

H+ ions

Kreb’s Cycle

lactic acid

mitochondria

NADH

O2

protein channels

pyruvate

split glucose

that occurs in the

That are used in

starting with

that

transports

that produces

that releases

combines with

to maintain the

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ILS Review—Cellular Respiration Define cellular respiration: ILS Review—Cellular Respiration

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116

Anaerobic

Cellular Respiration

Glycolysis

In: Out:

A) __________________________

Goes to the Kreb’s Cycle

1)_______________________ B) ___________________(Net)___

2)_______________________ C) __________________________

Goes to the Electron Transport System

C C C C C

C C C C

C

&

Where? ____________________________________

C C

Aerobic

Kreb’s Cycle

In: Out:

A) ________________________

1) ______________________

B) ________________________

Exhaled

2) ______________________ C) ________________________

Goes to the Electron Transport System

3) ______________________ A) ________________________

B) ________________________

Exhaled

C) ________________________

Goes to the Electron Transport System

C C C

C C C

Where? ____________________________________

Electron Transport System

In: Out/Process:

1) _____________

2) _____________

Between the inner and outer membrane of the

Where? ____________________________________

Inside of the mitochondria

________

_______ _______

______ ______

___ + ___ + ___ ADP + P

= A)______ & B)______

1031. Define cellular respiration:

2. Write the overall chemical equation for cellular respiration.

3. Our cells use the chemical energy in glucose to assemble ATP molecules that are then used as a direct energy source for cellular functions. Why make ATP molecules instead of directly using glucose?

4. The process of anaerobic respiration releases far less / more (circle one) energy than does aerobic respiration. Why is this so when both reactions start with one molecule of glucose?

5. Complete the chart as a review of cellular respiration:

Glycolysis Kreb’s Cycle Electron Transport System

Where it occurs

What happens

(what goes in what comes out)

# of ATP produced

Is O2 Needed?

If no O2 is present, what is produced?

118 Cellular Respiration Review

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6. Although the Kreb’s cycle only produces a few ATP molecules, it is crucial to cellular respiration. Why?

7. In terms of concentration, why do H+ ions move through the ATP synthase channels in the mitochondrial membranes?

8. What is the end result of the movement of those H+ ions?

9. In terms of cellular respiration, explain why it is that we breathe. The following are the two essay questions that will be on the quiz. You should prepare an answer to these ahead of time to be ready for the quiz. You will only need to answer one of the two questions. Bulleted terms/concepts need to be covered in your explanations for full credit.

1. Explain the first 2 stages of cellular respiration in as much detail as possible.

• Glycolysis & Kreb’s Cycle

• Inputs/Reactants for each stage

• Outputs/Products for each stage

• Anaerobic or Aerobic AND WHY!

• Where they each take place in the cell

2. Explain the specific role that oxygen plays in the electron transport system.

• H+

Concentration Gradient

• Oxygen and its role with electrons

• Origin of water

• ATP Synthase

• Mitochondria

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