chemistry i activities · web viewi will submit its content for periodic review to my...

CENTRO DE INVESTIGACIÓN YCENTRO DE INVESTIGACIÓN Y DESARROLLO DE EDUCACIÓN BILINGÜEDESARROLLO DE EDUCACIÓN BILINGÜE

PORTFOLIO 4 CHECKLISTSTUDENT NAME:

Your portfolio must include, the student agreement (signed) and the portfolio checklist

Act Description Activity Points

Earned Points

1 Diagnostic Activity 02 Knowledge Acquisition 103 Organization Activity 104 Application Activity 255 Metacognition 206 Integrative Activity 1 307 Lab. 5

Total

STUDENT’S REFLECTIONS ABOUT HIS/HER WORK:Presentation/Content/Activities________________________________________________________________________________________________________________________________________________________________________________________________________________________Feedback to Teacher:______________________________________________________Students’ Signature____________________________________ Date:____________

INTRODUCTION TO PORTFOLIOSEvery student must complete portfolio requirements each semester in order to be promoted to the next semester.Four (4) portfolios will be completed throughout this course. Detailed portfolio 1 requirements are listed on pages 5 and 6 in this handbook*, as well as an agreement that most be signed to ensure the understanding of the requirements for the present portfolio.The portfolio will be considered as a part of each student’s semiannual evaluation representing 40 % of its final grade (10% of each portfolio).For this course (), students will be using three (3) ring binders* to present paper portfolios.For this course the student may develop electronic activities for any of the portfolios using NEXUS.Rubrics and guides for portfolio contents are included in this handbook and should be used to ensure a high quality portfolio.

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BIOLOGY COMPETENCESGeneral skills and attributes 4. Listen, interprets and delivers relevant messages in different contexts through the use of media, tools codes and appropriate tools. • Expresses ideas and concepts through linguistic representations, mathematics or graphics.• Applies different communicative strategies depending who is the speaker, the context they are using and the objective they are looking for.• Identify the key ideas in a text or oral speech and infer conclusions from them. • Manages information technology and communication to obtain information and express ideas.6. Supports a personal stand on issues of interest and general relevance, considering other points of view critically and reflectively.• Choose information resources for a specific prototype and discriminates between them by relevance and reliability.• Evaluates arguments and opinions and identifies prejudices and fallacies.• Recognizes its own prejudices, modifies its point of view by discovering new evidence and finds new knowledge.• Structures ideas and argument in a clear, coherent and synthetic.

8. Participates and collaborates effectively in diverse teams. • Suggests ways of solving a problem or develop a team project, defining a course of action with specific steps.• Provides its point of view with an open mind and consider what others think in a reflexive manner.• Assumes a building activity with knowledge and abilities that can take upon different teams.

Disciplinary competencies6. Values the common preconceptions about various natural phenomena on the basis of scientific evidence.7- Explains the concepts underlying scientific notion that support the processes to solve everyday problems.

12.Applies safety standards in the handling of chemicals, instruments and equipment in carrying out their daily life activities.

Elements of competence: Defines the concepts of calories, cellular respiration, aerobic, anaerobic, mitochondria, glycolsis and

fermentation to relate them to the process of photo cellular respiration. Relates the mitochondria with the process of cellular respiration and identifies the importance of glucose in the

process of cellular respiration. Identifies the principal events of cellular respiration that occur in the cytoplasm and mitochondria. Values the importance of industrial fermentation.

P H A S E 4 A G R E E M E N TI ______________________________________________________ understand that my portfolio is a collection of my school work and related achievements. The contents exhibit my effort and progress as these elements relate to the goals represented in my instructional program.

I agree to accept the responsibility for creating and managing my portfolio as I complete each requirement. I will submit its content for periodic review to my instructor. In doing so, I understand that the contents of my portfolio, as well as the way in which I have presented the contents, will be evaluated for the purpose of judging my performance in school.

Student Signature: ________________________________ Date: ______________________

Parent Signature:I have read and understand the above portfolio agreement and have reviewed my child’s portfolio requirements.________________________________ Date: ______________________

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Stage 4: Cellular RespirationDiagnostic Activity

Learning Method IndividuallyKind of Evaluation Self assessmentTeaching Strategy QuestionnaireTeaching Resources Prior KnowledgeDue DatePossible Points 0

A. Answer the following questions.

1- Do you know how energy is taken out of the food?______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2- How do you explain this: Do you breathe through your nose or through your cells?______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3- Can you recognize the difference between cellular respiration and pulmonary respiration?______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

B- Comment with your classmates.

Knowledge Acquisition Activity

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Learning Method IndividuallyKind of Evaluation Peer- AssessmentTeaching strategy QuestionnaireTeaching Resources Biology, Miller and LevineDue DatePossible Points 10

Answer the following questions.

1. a. Review Why do all organisms need food?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Relate Cause and Effect Why do macromolecules differ in the amount of energy they contain?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2. a. Review Write the overall reaction for cellular respiration.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Apply Concepts How does the process of cellular respiration maintain homeostasis at the cellular level?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. a. Review In what ways are cellular respiration and photosynthesis considered opposite processes?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Use Analogies How is the chemical energy in glucose similar to money in a savings account?

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________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

4. a. Review What are the products of glycolysis?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Compare and Contrast How is the function of NAD+ similar to that of NADP+?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

5. a. Review What happens to pyruvic acid in the Krebs cycle?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Interpret Visuals Look at Figure 9–5 and list the products of the Krebs cycle. What happens to each of these products?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

6. a. Review How does the electron transport chain use the high energy electrons from glycolysis and the Krebs cycle?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Relate Cause and Effect How does the cell use the charge differences that build up across the inner mitochondrial membrane during cellular respiration?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

7. a. Review How many molecules of ATP are produced in the entire breakdown of glucose?

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________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Use Analogies How is the cell like a furnace?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

8. a. Review Name the two main types of fermentation.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Compare and Contrast How are alcoholic fermentation and lactic acid fermentation similar? How are they different?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

9. a. Review Why do runners breathe heavily after a sprint race?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

b. Sequence List the body’s sources of energy in the order in which they are used during a long-distance race.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

10. You have opened a bakery, selling bread made according to your family’s secret recipe. Unfortunately, most customers find the bread too heavy. Review what you have learned about chemical reactions in Chapter 2 and make a list of factors such as temperature that might affect

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the enzyme-catalyzed fermentation reaction involved in baking bread. Predict how each factor will affect the rate of fermentation and propose a solution for making the bread lighter by adding more bubbles to your family bread recipe.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

RUBRIC FOR KNOWLEDGE ACQUISITION ACTIVITY STAGE 4

Criteria 0FAIR

2.5GOOD

5EXCELLENT

Answers 4 questions unanswered or incorrect

3 questions (or less) unanswered or incorrect

All questions answered and correct

Organization ActivityLearning Method IndividuallyKind of Evaluation By teacher with rubricTeaching strategy FoldableTeaching Resources Biology, Miller and LevineDue DatePossible Points 10

1. - Make a foldable on the stages of photosynthesis and cellular respiration.

Take 2 pieces of paper (the example bellow uses 3 pieces of paper) and arrange them with 5 cm of difference. Fold the papers in half making sure all of the front pieces are like a stair. Staple at the top. Cut through the top three layers, at the middle of the book

.2- The top layer gets a title. One for photosynthesis and the other for cellular respiration. Every layer gets a specific name as the following example.

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3- Fill in every layer with the following information: Functions, Location, Reactants, Products, Equation and Importance. Include a colored drawing for photosynthesis and cellular respiration.

RUBRIC FOR ORGANIZATION ACTIVITY STAGE 4Criteria 0

FAIR1

GOOD2

EXCELLENTFoldable Is not organized or unclean,

pages of the same color**** Made using different color

pages its clean and organized

LabelsAll parts of each process must be labeled

Little or no labels. Numerous errors in labeling.

Missing steps or labels are incorrect. More than two spelling errors in labels.

All steps are labeled accurately with correct spellings in labels steps.

Process UnderstandingStudent must show an understanding of photosynthesis and cellular respiration

Lack of understanding of the two processes. Not able to describe each process and its purpose.Missing three or more components or mentioned incorrectly

Cycles not mentioned or are totally wrong.

Missing one of these requirements or not enough description.

Missing one component or used incorrectly

Parts of one cycle are incorrect.

Excellent understanding of both processes. Able to describe each process and its purpose, in depth, and using appropriate vocabulary.The three reactants and two products are included correctly.

Brief explanations are given of both cycles, including where they take place and reactants and products of both.

Images Images were not complete. There is an image per stage but colors are not used.

There is an image per stage and colors were used for every molecule.

NeatnessMake sure there are no smudges. All organelles are neatly done.

Very messy. Numerous smudges on project. Labels are messy and difficult to read.

Somewhat neat. Some effort in presentation and labels, but still some areas that are smudged. Labels are fairly neatly written.

Extremely neat and labeled. Much effort and pride in presentation. Above and beyond expectations.

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Application ActivityLearning Method In teamsKind of Evaluation By teacher with rubricsTeaching strategy PresentationTeaching Resources Online informationDue DatePossible Points 20

1- In teams on 5 make the following research.2- Topics will be assign by teacher:

a. Yogurtb. Beerc. Wined. Breade. Cottage cheesef. Sauerkraut

3- Make a PPT presentation that includes the following:a. Front page with the names of all team members (1 slide)b. Introduction. What is fermentation?(1 slide)c. How is this product produced in the industry? (4 or more slides)d. Diagram of the process. (1 slide)e. Find the chemical formula of this product. (1 slide)f. Are there different methods or products from the same fermentation? (2 or more

slides)g. Distinguish between the different products for example: In bread: white bread, oat

bread, black bread; in wine: red, white, pink, etc. (2 or more slides)h. Conclusion (1 slide)i. Bibliography. At least use 1 book from the library and at least 5 different internet

pages. Please quote them correctly APA. (1 slide)4- Present different pictures and process in the presentations.5- You must explain NO READING PLEASE!!!!6- It will be presented in plenary.

RUBRIC FOR APPLICATION ACTIVITY STAGE 3CRITERIA 0

FAIR2.5

GOOD5

EXCELLENTSUBJECT KNOWLEDGE

Student does not have grasp of information;

Student is at ease with expected answers to all

Student demonstrates full knowledge by

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student cannot answer questions about subject.

questions, without elaboration.

answering all class questions with explanations and elaboration

ORGANIZATION Audience cannot understand presentation because there is no sequence of information.

Audience has difficulty following presentation because student jumps around

Student presents information in logical, interesting sequence which audience can follow.

TEACHERS QUESTION

A student from the team answers the questions.

A random student answers incompletely.

A random student from the team answers the questions from the teacher.

Source Selection • Little or no background information is used. • Information is copied from the source

• At least 2 sources of information were used. Citation of source are poorly written. • Information somewhat related to the topic and written in the student’s own words.

• Information comes from at least 3 different sources (Internet, books, journals)• Information is cited properly and written in the student’s own words.

Metacognition ActivityLearning Method In teams of 5Kind of Evaluation Peer- EvaluationTeaching strategy QuestionnaireTeaching Resources Biology, Miller and Levine. On line researchDue DatePossible Points 20

Answer correctly all of the Chapter 9 Assessment.9.1 Understand Key Concepts1. Cells use the energy available in food to make a final energy-rich compound calleda. water. c. ATP.b. glucose. d. ADP.

2. Each gram of glucose contains approximately how much energy?a. 1 calorie c. 4 caloriesb. 1 Calorie d. 4 Calories

3. The process that releases energy from food in the presence of oxygen isa. synthesis. c. ATP synthase.b. cellular respiration. d. photosynthesis.

4. The first step in releasing the energy of glucose in the cell is known as

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a. fermentation. c. the Krebs cycle.b. glycolysis. d. electron transport.

5. Which of the following organisms perform cellular respiration?

a. only C c. only B and Db. only A and C d. all of the above

6. What is a calorie? Briefly explain how cells use a high-calorie molecule such as glucose.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

7. Write a chemical equation for cellular respiration. Label the molecules involved.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

8. What percentage of the energy contained in a molecule of glucose is captured in the bonds of ATP at the end of glycolysis?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

9. What does it mean if a process is “anaerobic”? Which part of cellular respiration is anaerobic?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Think Critically10. Use Analogies Why is comparing cellular respiration to a burning fire a poor analogy?

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________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

11. Compare and Contrast Why are cellular respiration and photosynthesis considered opposite reactions?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

9.2Understand Key Concepts12. The net gain of energy from glycolysis isa. 4 ATP molecules.b. 2 ATP molecules.c. 8 ADP molecules.d. 3 pyruvic acid molecules.

13. The Krebs cycle takes place within thea. chloroplast. c. mitochondrion.b. nucleus. d. cytoplasm.

14. The electron transport chain uses the high-energy electrons from the Krebs cycle toa. produce glucose.b. move H+ ions across the inner mitochondrial membrane.c. convert acetyl-CoA to citric acid.d. convert glucose to pyruvic acid.

15. How is glucose changed during glycolysis?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

16. What is NAD+? Why is it important?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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17. Summarize what happens during the Krebs cycle. What happens to high-energy electrons generated during the Krebs cycle?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

18. How is ATP synthase involved in making energy available to the cell?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Think Critically19. Compare and Contrast How is the function ofNAD+ in cellular respiration similar to that of NADP+ in photosynthesis?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

20. Compare and Contrast Where is the electron transport chain found in a eukaryotic cell? Where is it found in a prokaryotic cell?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

21. Sequence Explain how the products of glycolysis and the Krebs cycle are related to the electron transport chain. Draw a flowchart that shows the relationships between these products and the electron transport chain.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

22. Use Models Draw and label a mitochondrion surrounded by cytoplasm. Indicate where glycolysis, the Krebs cycle, and the electron transport chain occur in a eukaryotic cell.________________________________________________________________________________________________________________________________________________________

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________________________________________________________________________________________________________________________________________________________

9.3Understand Key Concepts23. Because fermentation takes place in the absence of oxygen, it is said to bea. aerobic. c. cyclic.b. anaerobic. d. oxygen-rich.

24. The process carried out by yeast that causes bread dough to rise isa. alcoholic fermentation.b. lactic acid fermentation.c. cellular respiration.d. yeast mitosis.

25. During heavy exercise, the buildup of lactic acid in muscle cells results ina. cellular respiration. c. fermentation.b. oxygen debt. d. the Krebs cycle.

26. How are fermentation and cellular respiration similar?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

27. Write equations to show how lactic acid fermentation compares with alcoholic fermentation. Which reactant(s) do they have in common?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Think Critically28. Infer Certain types of bacteria thrive in conditions that lack oxygen. What does that fact indicate about the way they obtain energy?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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29. Infer To function properly, heart muscle cells require a steady supply of oxygen. After a heart attack, small amounts of lactic acid are present. What does this evidence suggest about the nature of a heart attack?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

30. Predict In certain cases, regular exercise causes an increase in the number of mitochondria in muscle cells. How might that situation improve an individual’s ability to perform energy requiring activities?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

31. Formulate Hypotheses Yeast cells can carry out both fermentation and cellular respiration, depending on whether oxygen is present. In which case would you expect yeast cells to grow more rapidly? Explain.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

32. Apply Concepts Carbon monoxide (CO) molecules bring the electron transport chain in a mitochondrion to a stop by binding to an electron carrier. Use this information to explain why carbon monoxide gas kills organisms.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

RUBRIC FOR METACOGNITION ACTIVITY STAGE 4

Criteria 0FAIR

2.5GOOD

5EXCELLENT

Answers 4 questions unanswered or incorrect

3 questions (or less) unanswered or incorrect

All questions answered and correct

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Integrative ActivityLearning Method In teams of 5Kind of Evaluation By teacher with rubricsTeaching strategy Oral presentationTeaching Resources Biology, Miller and LevineDue DatePossible Points 30

Cellular Respiration1- In teams of 5 make a PPT presentation.2- In the presentation the following information MUST be explained in at least 1 slide per

question: a) Chemical formula for Photosynthesis or Cellular respiration with graphicb) Light absorption, colors used, type of chlorophyll with graphic for photosynthesis.c) Identify the macromolecules that provide the fuel for cellular respiration and which is the most

immediate source of energy.d) Structures in plants related to photosynthesis or Structures in animals related to Cellular Respiratione) Conversion of light energy into chemical energy (both reactions, energy obtained: ATP) f) Cellular Respiration: Conversion of glucose into chemical energy: ATPg) Must include graphics for both processes (letter e and f)h) What is the most usable form of energy for living things?i) Fully explain what happens when glucose supplies have been depleted.j) During the process of cellular respiration, how much energy is used to make ATP and

what happens to the rest of the energy?k) What molecules are produced from glucose in cellular respiration?l) As glucose molecules are broken down energy is released. What happens to those

electrons?m) What is the final electron acceptor in the transport chain? What happens to that

acceptor?n) What function does the electron transport chain serve in cellular respiration?

3- A game MUST be added to the presentation to review all of the important concepts of the chapter. Small gifts or candy can be used. 10 to 15 questions MUST be presented.

RUBRIC FOR INTEGRATIVE ACTIVITY STAGE 4

CriteriaFAIR GOOD EXCELLENT

Title Slide 0The slide lacks of information.

*******

1This slide features the title of the presentation and includes the author's name(s), class period, date and assignment name. A graphic or picture is included that relates to the

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most important concept of the presentation.(The title should be the largest font on the slide)

Report ofResearch

Main body slides

The sections of the presentation were correctly answered:(1 point each)

a b c d e f g

h i j k l m n

SUBJECT KNOWLEDGE

0Student does not have grasp of information; student cannot answer questions about subject.

2.5Student is at ease with expected answers to all questions, without elaboration.

5Student demonstrates full knowledge by answering all class questions with explanations and elaboration

Font

Contrast

Images and Layout

0Font on all slides is too small to be read at a distance.

The lack of contrast between the font and background makes the text impossible to read.

Images are distracting decorations that create a busy feeling and detract from the content. Layout is cluttered and confusing.

2.5Font on most slides is too small to be read at a distance.

The lack of contrast between the font and background makes the text difficult to read.

Most images are clipart. Images are too large/small in size, or of poor quality (fuzzy). Layout shows some structure.

5Font on all slides is large enough to be read at a distance.

There is good contrast between the font and background on all slides.

All slides contain one powerful,high-quality image per slide which helps audience understand the content. Layout is visually pleasing.

Ability to construct a variety of question types to help solve game problems

0Unable to construct knowledgeable questions.

2.5Correctly constructed between 5 to 9 knowledgeable questions in several different types.

5Correctly constructed 10to 15 knowledgeable questions in several different types. For example, closed or multiple choice, true or false, and analytical or evaluative questions.

Lab Session: FermentationLearning Method In teams of 4Kind of Evaluation IndividuallyTeaching strategy Hands onTeaching Resources Biology, Miller and Levine.Due DatePossible Points 5

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Blow Up a Balloon with Cellular Respiration Introduction: Yeasts are unicellular microorganisms of the fungi kingdom. They are facultative anaerobe, which means that they can respire or ferment depending upon environmental conditions. In the presence of oxygen, respiration takes place (aerobic respiration). Without oxygen present, fermentation occurs (anaerobic respiration). Both processes require sugar to produce cellular energy. Here is the chemical reaction of fermentation, which produces ethanol and carbon dioxide as metabolic waste products.

Objective: In this lab, students will use the respiration powers of yeast to blow balloons. This activity will reinforce the basic principles of respiration as a fundamental metabolic process for living organisms using yeast as a model. It will also explore how humans use this biological knowledge in everyday life. Material:

balloons narrow funnel 1 tablespoon (15mL) active dry yeast 1 teaspoon (5 mL) sugar measuring spoons measuring cup warm water ruler

Safety: Remind students there is NO eating or drinking in the lab. Students must not attempt to inflate the balloons with their mouths, especially after it is filled with the reacting agents.

Procedure: 1. Place the bottom of a funnel into the opening of the balloon. You may need to stretch the opening of the balloon a little bit so that it fits. 2. Have a carefully supervised student pour the yeast and the sugar into the balloon through the funnel. Then fill the measuring cup with warm water from the sink and carefully pour the water into the balloon. 3. Remove the funnel from the opening of the balloon. Tie a knot in the balloon to keep the water-and-yeast mixture inside. Measure your balloon. 4. Place the balloon in a warm place and wait. Measure your balloon again. 5. Now sit back and wait as the balloon gets bigger and bigger.

Discussion:

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1. What are the reactants in the observed reaction? ____________________________________________________________________________2. What are the products? ____________________________________________________________________________3. What is the purpose of warm water? ________________________________________________________________________________________________________________________________________________________4. Why is respiration important for living organisms? ________________________________________________________________________________________________________________________________________________________5. How do people use the respiration powers of yeast? Or more specifically, what things can you make with yeast? ________________________________________________________________________________________________________________________________________________________

The yeast uses the sugar and warm water to grow. Warm water provides heat to the yeast reaction and accelerates it. As yeast grows it expands and gets bubbly. By being “bubbly” the yeast gives off carbon dioxide, the same gas that your body produces when you breathe, and the gas inflates the balloon. The yeast also produces ethanol. Respiration provides organisms with the energy to do cellular work that helps them grow, function, and live. People use yeast to bake because during fermentation carbon dioxide forms bubbles in the dough and expand it. Since baking is done at high temperatures, yeast ultimately dies and nearly all the ethanol evaporates. Ethanol fermentation is used to produce alcoholic beverages. People also use yeast fermentation to make ethanol for fuel.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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chemistry i activities · web viewi will submit its content for periodic review to my...

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