Taks objective 2 – The student will demonstrate an understanding of living systems and the environment



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TEKS 9B

Cellular Respiration

TAKS Objective 2 – The student will demonstrate an understanding of living systems and the environment.

TEKS Science Concepts 9 B

The student knows metabolic processes and energy transfers that occur in organisms. The student is expected to:


  1. compare the energy flow in photosynthesis to the energy flow in cellular respiration

For Teacher’s Eyes Only

Teacher Background:

Cellular respiration is a complex concept that must be taught. In these activities, we will introduce cellular respiration and its components to students. In later activities, students will be able to compare the energy flow of cellular respiration to photosynthesis. A brief description of cellular respiration follows:

Cellular Respiration – .

Student Prior Knowledge

Students should be familiar with the components associated with body systems TEKS 6.10 (C) identify how structure complements function at different levels of organization including organs, organ systems, organisms, and populations and the functions of these systems.

5 E’s


ATP, ENERGY!


ENGAGE

Obtain small Nerf Toys that shoot soft darts. As students are waiting to begin class, shoot the soft darts around the room. This toy is a great representation of the molecule ATP. Tell students that our body obtains energy by making a molecule called ATP from the foods we eat. Show students the picture of the molecule and describe which parts represent Adenine (handle), Ribose (barrel) and Phosphates (dart). Later on during the lesson, students will see that when ATP looses a phosphate it give off energy, which is represented in the shooting of the dart.

EXPLORE

Exploration 1

Cellular Respiration Simulation Activity

Activity Overview: This is a role-playing simulation where the students act as the enzymes of cellular respiration to break down a glucose "molecule."  The purpose of the activity is to review the "big picture" of metabolism, aiding students in understanding the relationship among glycolysis, the Kreb's cycle, and the ETC. See Blackline Masters for the simulation layout and detailed directions.



Exploration 2

Muscle Fatigue

Students work in pairs to complete the following experiment to investigate the relationship between oxygen and muscle fatigue. Use the following procedure to explore lactic acid buildup in muscles.



  1. Each pair of students is given a tennis ball.

  2. Partner A holds the ball in his or her hand. Either hand is OK.

  3. Partner B monitors the time for two minutes.

  4. When Partner A says begin, Partner B squeezes the tennis ball with his or her hand as many times as possible until time is called at the end of two minutes. Simultaneously, Partner A will count aloud the number of times the tennis ball is squeezed.

  5. Create a data table and record Partner A’s data.

  6. Partners switch roles, and repeat steps 2-4.

  7. Record Partner B’s data.

Provide a debriefing for the activity using the following questions:

  1. Describe how your hand felt at the end of the activity? Answers will vary but should include responses related to discomfort or pain.

  2. What is happening to the muscles in your hand? The muscles are requiring more oxygen than the blood can deliver (oxygen debt). As oxygen levels decrease, the muscle cells form lactate, which causes discomfort or pain.

  3. How do swimmers overcome lactate buildup as they near the end of a race? Initially, creatine phosphate powers the muscles during the race. However, near the end of the race, the swimmer uses rapid breathing to restore the oxygen supply to the muscles. The lactate diffuses out of the muscles and into blood where it be carried to the liver for conversion to glucose. The glucose is transported back to the muscle cells for cellular respiration to synthesize ATP which is used to regenerate creatine phosphate.

  4. Which body systems are interacting together in this learning experience? Answers will vary, but might include the following: circulatory, respiratory, nervous, muscular. Students should be able to describe how these systems interact directly or indirectly.

EXPLAIN

ELABORATE



Elaboration 1

Respiration Labs (Blackline Masters)

Students will perform three different laboratory experiments that review and further explain the process of cellular respiration

EVALUATE

1. Working in a group and given 40 minutes, the student will design and implement an experiment to demonstrate the relationship between heart, respiration rates, and lactic acid build up in muscles. A minimum score of 70% on the “Check Sheet for Independent Investigations is required.


Check Sheet for Independent Investigations






I.

Stating a problem to investigate

Problem phrased as a research question

If…then hypothesis statement





5

II.

Develop a procedure to compare baseline heart and respiration rates to an after exercise heart and respiration rates.

All steps in sequential order and reproducible

Multiple trials indicated

Materials are appropriate and described






15

III.

Gathering respiration and heart rate data

Data organized in table or chart

Data has a title

Labels for manipulated & responding variables

Units are stated

Multiple trials, totals and averages are included






15

IV.

Graphing data

Appropriate graph type used

Appropriate scale, range, and interval are used

Graph has a title

Descriptive label for variable on the x-axis and

responding variable for the y-axis

Graphed data matches data collected. Units

indicated for each axis






20

V.

Data analysis

Results from graph clearly stated

Inferences made about results





20

VI.

Conclusion

Conclusions based on results and inferences

Hypothesis is restated

Hypothesis is accepted or rejected






25

2. Using notes and text, students must correctly map 10 of 14 terms on the completed Cellular Respiration Concept Map (Blackline Masters).



Cellular Respiration Role Play

Purpose:

To review the "big picture" of metabolism, aiding students in understanding the relationship among glycolysis, the Kreb's cycle, and the ETC.  See Diagram 1 for the simulation layout.



Materials:

4 tissue boxes , 1 large piece of construction paper, stack of recipe index cards to be laminated, 1/4 lb. bag of balloons, 1 package of disposable drinking cups, colored markers, Velcro dots, printed student role cards




Safety Considerations:

Students with latex allergies should be provided with an alternative activity. Students with asthma should not be assigned to an area that requires them to blow up balloons.



Procedure:
Teacher's prep before class:     
Label the index cards with the desired colors as follows then laminate:

  • 8 index cards "NAD"

  • 2 "FAD"

  • Leave enough room after the "NAD" and "FAD" that an "H" could be inserted using a Velcro dot.  

  • 6 "CO2"

  • 2 "Acetyl CoA".  

  • Cut 5 index cards into thirds Label 8 pieces with an "H" 2 pieces with "H2", and 4 with "e-". Laminate

  1. Construction Paper Draw 6 "carbon" circles on the side of the paper (3 circles on each half and label under each half “pyruvic acid”). Label across the 6-C molecule “Glucose”.

GLUCOSE

PYRUVIC ACID PYRUVIC ACID



  1. Label tissue box #1 “CO2 Waste”, tissue box #2 “NADH“, tissue box #3 “FADH2”, and tissue box #4 “e-“

  2. Inflate 2 balloons and label ATP.

  3. Fill 2 cups of water

Classroom Set Up

1


Glycolysis Area (Cytoplasm)

(Materials and People Needed)

NAD Runner

Enzyme Person

(NAD, e-, ATP Inflated Balloons, and Glucose Molecule)
. The classroom should be set up with a glycolysis area, transition station, Kreb's cycle area, and ETC area (see Diagram 1).


Transition Area

(Materials and People Needed)

Transition Person

(NAD, e -, CO2 and Acetyl Co-A)






Kreb’s Cycle Area (Mitochondrial Matrix)

3 Carbon Compound People

NAD Runner/FAD Runner

(NAD, FAD, e-, CO2, H2 and H)





ETC (Mitochondrial Membrane)

ATP Synthase Person

NAD + H Acceptor Individual

FAD + H2 Acceptor Individual

Water Person (Stands in opposition to everyone else and uses the e-)

Intermembrane Space Person (Builds up the H+ ion concentration)

ATP Synthase Person


Activity Script:


  1. Assign 13 students an assignment in the first attempt of the role play.

  2. Have all the students read their job assignment through one time before beginning the role play activity.

  3. The first student in the glycolysis pathway receives the 6 carbon glucose molecule.  The student states "I'm an enzyme that converts the 6 carbon glucose molecule into two three carbon molecules.  I require ATP to do this."  The student receives 2 ATP balloons and pops them and then rips the glucose molecule into two equal halves. This student will give a NAD to a NAD Runner.

  4. The student then passes two equal halves of the construction paper to the next person in the transition area.

  5. The student at the transition area will convert the 3-C molecule to Acetyl Co-A by attaching the Acetyl-Co-A card to both of the 3 carbon molecules (Halves of the construction paper) and then take an NAD+ index card and give it the runner who will attach an "H" to make an NADH molecule. The runner should take the NADH molecule to the NAD+H collector at the ETC.

  6. Now the transition student will pass one of the Acetyl Co-A molecules into the Kreb’s cycle.

Person 1 ---- “I am now citric acid a 6-Carbon Molecule” While handing off the box to person two, “I give off CO2 losing a carbon while transforming NAD to NADH”

Person 2 ---- “I am now a 5 Carbon Molecule” While handing off the box to person three, “I give off CO2 losing another carbon while transforming NAD to NADH and make an ATP molecule” (Blows up a balloon)

Person 3---- “I am now a 4 Carbon Molecule, I transform NAD to NADH and FAD to FADH2” Place the first box aside.

Repeat with second half of construction paper.

Person 1 ---- “I am now citric acid a 6-Carbon Molecule” While handing off the paper to person two, “I give off CO2 losing a carbon while transforming NAD to NADH”

Person 2 ---- “I am now a 5 Carbon Molecule” While handing off the box to person three, “I give off CO2 losing another carbon while transforming NAD to NADH and make an ATP molecule” (Blows up a balloon)

Person 3---- “I am now a 4 Carbon Molecule, I transform NAD to NADH and FAD to FADH2” Place the second box aside.


  1. NAD+H Acceptor removes the H and the gives it to the intermembrane space. Pass an e- to the next person

  2. FAD+H2 Acceptor removes the H2 and gives it to the intermembrane space. Place the e- in the electron box.

  3. Intermembrane space collects at least 4 H molecules and passes them one at a time to the ATP Synthase.

  4. ATP Synthase person blow up a balloon (ATP) for every H+ received from intermembraneous space. “I convert ADP to ATP”

  5. ATP Synthase passes the H+ to the Water Person to the left who produces two H2O molecules with every 4 H+ received. After receiving 4 H+ the Water Person takes an e- from the electron box and places the e- with 4 H+ into the water box and pours a cup of water.

When the first role play is complete, have students change roles and repeat the role play activity.

Front of Card


Glycolysis



NAD Runner


B
Job:

Your job is to collect NAD and e- from the Glycolysis area and attach a H ion. Transport the NADH to the NAD + H Acceptor in the Electron Transport Chain.

Say:

I collect H ions and electrons and transport them to the Electron Transport Chain
ack of Card


F
Transition Area

NAD Runner
ront of Card


Back of Card


Job:

Your job is to collect NAD and e- from the Transition area and attach a H ion. Transport the NADH to the NAD + H Acceptor in the Electron Transport Chain.

Say:

I collect H ions and transport them to the Electron Transport Chain


Front of Card


Kreb’s Cycle



NAD Runner


Back of Card


Job:

Your job is to collect NAD and e- from the Kreb’s cycle area and attach a H ion. Transport the NADH to the NAD + H Acceptor in the Electron Transport Chain.

Say:

I collect H ions and transport them to the Electron Transport Chain


F
Enzyme
ront of Card


Back of Card


Job:

Your job is to lower the activation energy that allows glucose to be split into 2, 3 Carbon molecules.

Say:

"I'm an enzyme that converts the 6 carbon glucose molecule into two three carbon molecules.  I require ATP to do this." Pick up and pop 2 ATP Balloons then rip the glucose molecule in half. Then take an NAD+ index card and give it the NAD Runner and then blow up 4 ATP Balloons.  


F
Transition
ront of Card


Back of Card


Job:

You will convert the 3-C molecule to Acetyl Co-A by attaching the Acetyl-Co-A card to both of the 3 carbon molecules and then take an NAD+ index card and give it the runner who will attach an "H" to make an NAD + H Acceptor. Also, place a CO2 in the “CO2 Waste”.  

Say:

Glucose must go through some transitions before it can proceed through other stages of cellular respiration. Here the 3-C molecule becomes Acetyle Co-A. Attach the Acetyl Co-A molecule to both of the 3-C molecules. Give an NAD to the NAD Runner and get rid of CO2.


F
Kreb’s Cycle

6-C Molecule

Citric Acid
ront of Card


Back of Card


Job:

You are one of the intermediate carbon molecules that will eventually regenerate the starting molecule for the Kreb’s cycle.

Say:

I am now citric acid a 6-Carbon Molecule.” While handing off the box to person two, “I give off CO2 losing a carbon while transforming NAD to NADH” Toss a CO2 molecule in the “Waste” box and hand an NAD to the NAD Runner.




F
Kreb’s Cycle

5-C Molecule
ront of Card


Back of Card


Job:

You are the second of the intermediate carbon molecules that will eventually regenerate the starting molecule for the Kreb’s cycle. You also produce a molecule of ATP.

Say:

“I am now a 5 Carbon Molecule” While handing off the box to person three, “I give off CO2 losing another carbon while transforming NAD to NADH and make an ATP molecule” (Blow up a balloon) Toss a CO2 molecule in the “Waste” box and hand an NAD to the NAD Runner.




F
Kreb’s Cycle

4-C Molecule
ront of Card


Back of Card


Job:

You are the last of the intermediate carbon molecules that will eventually regenerate the starting molecule for the Kreb’s cycle.

Say:

“I am now a 4 Carbon Molecule, I transform NAD to NADH and FAD to FADH2” Toss a CO2 molecule in the “Waste” box and hand an NAD to the NAD Runner. Place the first box aside and repeat with the second box .




F
NAD + H

Acceptor
ront of Card


Back of Card


Job:

You will remove the H ion and give it to the intermembranous space to assist in the H build up. You will also pass an e- to the next person

Say:

I assist with the build-up of H ions in the intermembrane space and pass e- down the ETC.


Front of Card


ETC



FAD + H2

Acceptor


Back of Card


Job:

You will remove the H ion and give it to the intermembrane space to assist in the H build up. You will also pass an e- to the next person

Say:

I assist with the build-up of H ions in the intermembrane space and pass e- down the ETC.


Front of Card


Intermembrane Space



H+ Build Up


Back of Card


Job:

This is an area of the mitochondria that allows the excessive build-up of H ions.

Say:

I collect an over abundance of H ions.


Front of Card


ATP Synthase




Back of Card


Job:

You make the most ATP in cellular respiration process. You take all the built up H ions and use their energy to change ADP to ATP.

Say:

I convert ADP to ATP”. Blow up a balloon (ATP) for every H+ received from intermembrane space




Front of Card


E- Acceptor



Water Producer


Back of Card


Job:

You produce water by combining O2 and H ions that are used by ATP Synthase. You also contribute to the H ion concentration in the intermembrane space.

Say:

I produce water as a waste product of cellular respiration.


Respiration Review Lab

Overview:

We eat food to provide our bodies with energy. However, trying to use food molecules like glucose to run our bodies is like trying to run a car wash with a five dollar bill. Your cells can only use the chemical bond energy stored in ATP molecules to run cellular operations just as the car wash will only run on dollars or quarters. Therefore, the cell must change food molecules like glucose into usable form --- ATP. This process is called cellular respiration.



Let’s compare the burning of glucose in the body to the burning of a candle. Glucose molecules provide energy for the body just like the candle wax provides energy for the burning flames. The following experiments will provide some information about processes involved in the burning of a candle that also apply to the “burning” of glucose in the body.

Materials per Group:

  • Large candle

  • 500 ml Erlenmeyer Flask

  • Matches

  • Aluminum pie plates

  • Water

  • Bromothymol Blue

Experiment #1

Materials:

  • Candle

  • Matches


Procedure/Observations:

  1. Light the candle and allow it to burn.

    1. What provided the spark to start the candle burning?

    2. What provides the fuel for the burning candle?

  2. Is the burning candle giving off any type of energy?

If so, what kind(s) of energy are being released?

  1. Place the beaker or flask over the candle. What happens?

  2. What caused the candle to go out?

  3. What gas is necessary for the candle to burn efficiently?

  4. What provides the “spark” to get cellular respiration started in the cell?

  5. Is energy released when glucose is “burned” in the cell?

If so, what kind of energy is released?

  1. Why isn’t heat released in large quantities in the cell?

  2. Is the same gas necessary to “burn” glucose efficiently in the body as is needed to burn the candle efficiently?

  3. What is the gas that is needed to break down glucose into ATP efficiently?

  4. Where in the cell is glucose broken down in the presence of this gas?

  5. What is the name for this type of cellular respiration?

  6. How many ATP’s (net) can be gained if a glucose molecule is completely broken down with oxygen?

  7. If oxygen was not present, how many ATP’s (net) could be gained from a glucose molecule being broken down?

  8. What is the term for the breakdown of glucose into ATP without oxygen?

  9. Where in the cell does the process described in #15 take place?

  10. Explain why it is so important that oxygen be present to breakdown glucose.

  11. How long can the candle burn without oxygen?

  12. How long do you think a cell can run without oxygen?

Experiment #2

Materials:

  • Candle

  • Matches

  • 500 ml Erlenmeyer Flask

  • Bromothymol Blue

  • Aluminum Pie Plate

Procedures/Observations:

  1. Light the candle again and allow it to burn.

  2. Place the flask over the candle and leave it until the candle goes out.

  3. Slide the flask quickly up and over the candle and cover the bottom of the flask with your hand, trying not to let any of the contents escape. Turn the flask right side up.

  4. Carefully move your hand from the top of the flask just enough to add 2 drops of Bromothymol Blue then cover the top completely again.

  5. What color was the Bromothymol Blue to begin with?

  6. What color did the Bromothymol Blue turn when placed in the beaker? (You may have to swirl the liquid and wait a minute or two for a change.)

  7. Do you notice any water vapor on the inside of the flask?

  8. Is water also a waste product (by product) of cellular respiration?

  9. Bromothymol Blue is a pH indicator. Carbonic acid forms in the presence of water and high concentrations of what gas?

  10. What gas was given off as a waste product of the burning candle?

  11. What gas is given off as a waste product of cellular respiration?

Experiment #3

Materials:

  • Candle

  • Matches

  • 500 ml Erlenmeyer Flask

  • Water

  • Aluminum Pie Plate

Procedures/Observations:

    1. Pour enough water in the bottom of the pan to fill the pan at least half-full.

    2. Light the candle and let it burn. Set the base of the candle in to the water in the middle of the pan and let it continue to burn.

    3. Place the flask over the candle, submerging it in the water.

    4. What happens when the candle goes out?

    5. What was removed from the air in the flask to allow space for the water to come in?

    6. Carbon dioxide is released into the air during the burning of the candle. However, much of this carbon dioxide becomes dissolved in the water to form carbonic acid. This provides even more space for the water to rush in.

Conclusions:

  1. Write the balanced, general formula for cellular respiration.



  1. ________________, ___________________ and ___________________ are the materials necessary for respiration to take place in the cell.



  1. _____________________, ___________________, and ____________________ (_______________) are given off during cellular respiration.

Respiration Review Lab

Key

Overview:

We eat food to provide our bodies with energy. However, trying to use food molecules like glucose to run our bodies is like trying to run a car wash with a five dollar bill. Your cells can only use the chemical bond energy stored in ATP molecules to run cellular operations just as the car wash will only run on dollars or quarters. Therefore, the cell must change food molecules like glucose into usable form --- ATP. This process is called cellular respiration.



Let’s compare the burning of glucose in the body to the burning of a candle. Glucose molecules provide energy for the body just like the candle wax provides energy for the burning flames. The following experiments will provide some information about processes involved in the burning of a candle that also apply to the “burning” of glucose in the body.

Materials per Group:

  • Large candle

  • 500 ml Erlenmeyer Flask

  • Matches

  • Aluminum pie plates

  • Water

  • Bromothymol Blue

Experiment #1

Materials:

  • Candle

  • Matches

  • 500 ml Erlenmeyer Flask

  • Aluminum Pie Plate


Procedure/Observations:

  1. Light the candle and allow it to burn.

    1. What provided the spark to start the candle burning? Match

    2. What provides the fuel for the burning candle? Wax and Oxygen

  1. Is the burning candle giving off any type of energy? Yes

If so, what kind(s) of energy are being released? Heat & Light

  1. Place the beaker or flask over the candle. What happens? Flame goes out.

  2. What caused the candle to go out? Uses all of oxygen.

  3. What gas is necessary for the candle to burn efficiently? Oxygen

  4. What provides the “spark” to get cellular respiration started in the cell? Enzymes

  5. Is energy released when glucose is “burned” in the cell? Yes

If so, what kind of energy is released? ATP or chemical energy

  1. Why isn’t heat released in large quantities in the cell? Would kill the cell (98.6 oF normal)

  2. Is the same gas necessary to “burn” glucose efficiently in the body as is needed to burn the candle efficiently? Yes

  3. What is the gas that is needed to break down glucose into ATP efficiently? Oxygen

  4. Where in the cell is glucose broken down in the presence of this gas? Mitochondria

  5. What is the name for this type of cellular respiration? Aerobic Respiration

  6. How many ATP’s (net) can be gained if a glucose molecule is completely broken down with oxygen? 36

  7. If oxygen was not present, how many ATP’s (net) could be gained from a glucose molecule being broken down? 2

  8. What is the term for the breakdown of glucose into ATP without oxygen? Anaerobic respiration (glycolysis/fermentation)

  9. Where in the cell does the process described in #15 take place? Cytoplasm

  10. Explain why it is so important that oxygen be present to breakdown glucose. More efficient and make more ATP’s

  11. How long can the candle burn without oxygen? not long (can’t)

  12. How long do you think a cell can run without oxygen? not long (few minutes)

Experiment #2

Materials:

  • Candle

  • Matches

  • 500 ml Erlenmeyer Flask

  • Bromothymol Blue

  • Aluminum Pie Plate

Procedures/Observations:

  1. Light the candle again and allow it to burn.

  2. Place the flask over the candle and leave it until the candle goes out.

  3. Slide the flask quickly up and over the candle and cover the bottom of the flask with your hand, trying not to let any of the contents escape. Turn the flask right side up.

  4. Carefully move your hand from the top of the flask just enough to add 2 drops of Bromothymol Blue then cover the top completely again.

  5. What color was the Bromothymol Blue to begin with? Blue

  6. What color did the Bromothymol Blue turn when placed in the beaker? (You may have to swirl the liquid and wait a minute or two for a change.) Green (yellow-green)

  7. Do you notice any water vapor on the inside of the flask? Yes

  8. Is water also a waste product (by product) of cellular respiration? Yes

  9. Bromothymol Blue is a pH indicator. Carbonic acid forms in the presence of water and high concentrations of what gas? Carbon Dioxide

  10. What gas was given off as a waste product of the burning candle? Carbon Dioxide

  11. What gas is given off as a waste product of cellular respiration? Carbon Dioxide

Experiment #3

Materials:

  • Candle

  • Matches

  • 500 ml Erlenmeyer Flask

  • Water

  • Aluminum Pie Plate

Procedures/Observations:

    1. Pour enough water in the bottom of the pan to fill the pan at least half-full.

    2. Light the candle and let it burn. Set the base of the candle in to the water in the middle of the pan and let it continue to burn.

    3. Place the flask over the candle, submerging it in the water.

    4. What happens when the candle goes out? Water comes into the flask

    5. What was removed from the air in the flask to allow space for the water to come in? Oxygen

    6. Carbon dioxide is released into the air during the burning of the candle. However, much of this carbon dioxide becomes dissolved in the water to form carbonic acid. This provides even more space for the water to rush in.

Conclusions:

  1. Write the balanced, general formula for cellular respiration.

C6 H12 O6 + 6O2  6CO2 + 6H2O + energy (ATP’s)

  1. Enzymes, glucose and oxygen are the materials necessary for respiration to take place in the cell.

  2. Carbon dioxide, water and ATP (energy) are given off during cellular respiration.

Muscle Fatigue

Working in pairs, complete the following experiment to investigate the relationship between oxygen and muscle fatigue. Use the following procedure to explore lactic acid buildup in muscles.



  1. Each pair of students should receive a tennis ball.

  2. Partner A holds the ball in his or her hand. Either hand is OK.

  3. Partner B monitors the time for two minutes.

  4. When Partner A says begin, Partner B squeezes the tennis ball with his or her hand as many times as possible until time is called at the end of two minutes. Simultaneously, Partner A will count aloud the number of times the tennis ball is squeezed.

  1. Create a data table and record Partner A’s data.

  2. Partners switch roles, and repeat steps 2-4.

  3. Record Partner B’s data.

Questions:

  1. Describe how your hand felt at the end of the activity?



  1. What is happening to the muscles in your hand?



  1. How do swimmers overcome lactate buildup as they near the end of a race?



  1. Which body systems are interacting together in this learning experience?



  1. After participating in the Respiration and Muscle Rumble write a 100-150-word summary about oxygen debt and muscular contractions.

WORD BANK

1 ATP
2 ATP
36 ATP
4 NADH
1 FADH
Electron transport chain
Mitochondrion
Cytoplasm
Fermentation
Glycolysis
Glucose
Pyruvate
Lactic acid
Kreb's Cycle



T
TEKS 7.9 A
AKS Objective 2 page



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