B2 Chloroplast Blast: Photosynthesis Key Question: How Does Photosynthesis Work, and Why Is It Important?

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INVESTIGATION B2 B2 Chloroplast Blast: Photosynthesis Key Question: How does photosynthesis work, and why is it important?

In this investigation, students will work in teams and yy Carbon atoms, 6 per team of 2 play the Chloroplast Blast game, moving around the yy Glucose molecule holder, 1 per team of 2 light reactions and the the Calvin cycle and answering questions in order to build a glucose molecule. yy Number cube yy Level B card set Learning Goals yy Completed App Map from previous investigation, ✔✔Compare and contrast the two stages of 1 per student photosynthesis: the light reactions and the Calvin cycle. Online Resources Available at www.curiosityplace.com ✔✔Model the energy dynamics of photosynthesis. ✔✔Relate photosynthesis to botany, ecology, and Student Vocabulary Words example organisms. ADP – adenosine diphosphate, an organic molecule composed of a molecule of adenine, a 5-carbon sugar called ribose, and two phosphate groups. It is the low- GETTING STARTED energy version of ATP and is produced during the Calvin cycle and converted into ATP during the light reactions. Time 50 minutes per game (play the game multiple ATP – adenosine triphosphate, an organic molecule times for increased fun and effectiveness) composed of a molecule of adenine, a 5-carbon sugar called ribose, and three phosphate groups. This high- Setup and Materials energy molecule is produced by the light reactions and 1. Make copies of investigation sheets for students. used in the Calvin cycle. 2. The game can be played in groups of 4–6. Calvin cycle – the stage of photosynthesis in which 3. Each group of players will need the Level B card set. carbon dioxide is used to make 3-carbon precursors of ™ glucose 4. Make sure students set aside the LEARN target card and then shuffle the card set before starting carbon dioxide – CO2, the starting substance for the the game. Calvin cycle. chloroplast – the organelle in which photosynthesis Materials for each group takes place yy Chloroplast Blast game board glyceraldehyde-3-phosphate – G3P, the 3-carbon yy Player marker tokens precursor to glucose, made during the Calvin cycle grana – stacks of thylakoids yy High-energy molecule tokens

NGSS Connection This investigation builds conceptual understanding and skills for the following performance expectation. HS-LS1-5. Use a model to illustrate how photosynthesis transforms light energy into stored chemical energy.

Science and Engineering Practices Disciplinary Core Ideas Crosscutting Concepts

Developing and Using Models LS1.C: Organization for Matter and Energy Flow Energy and Matter in Organisms PS3.D: Energy in Chemical Processes and Everyday Life

Energy Quest 55 Chloroplast Blast: Photosynthesis

TEACHER BACKGROUND light reactions – the stage of photosynthesis during mesophyll cells – type of leaf cell that contains which sunlight is captured and, along with water, used to chloroplasts (ADD) produce oxygen, ATP, and NADPH By now, you’ve explored photosynthesis in depth using lumen – the inner space of the thylakoid ™ the LEARN app, and are ready to play Chloroplast NADP+ – low-energy version of NADPH; electron carrier Blast! If you would like a detailed review of photosynthesis, without electrons go to the background section for Investigation A1. Here, NADPH –high-energy electron carrier we will focus on relating the game to the process, giving ribulose-1,5-bisphosphate – RuBP, the 5-carbon you a behind-the-scenes look at the design of the board, molecule that combines with carbon dioxide and is later answering questions, and reviewing gameplay action. regenerated during the Calvin cycle Chloroplast Blast, like photosynthesis, takes place in the stroma – the inner space of the chloroplast where the chloroplast, an organelle found mainly in mesophyll Calvin cycle takes place cells of leaves. While most chloroplasts are found in thylakoids – the membrane-bound compartments the leaves of plants, other green plant structures such within the chloroplast in which the light reactions as stems and unripe fruit contain these organelles as take place well. Even plants with reduced leaves, such as cacti, and some protists, such as algae and phytoplankton, have chloroplasts, allowing them to perform photosynthesis.

Similar to photosynthesis, the board is separated into two regions—the light reactions and the Calvin cycle.

Leaf Leaf Cross Section Mesophyll Cell

Mesophyll Cell wall Chloroplast

Vacuole Nucleus Cytoplasm Stoma

Starch grain Thylakoid Outer membrane Intermembrane space Inner membrane Granum (stack of thylakoids) Stroma Thylakoid space Chloroplast

56 B2

PLAYING THE GAME

The game lists glucose as the result of the Calvin cycle for simplicity. The 3-carbon molecule G3P actually exits the cycle and is subsequently converted to glucose or other carbohydrates.

When the Calvin cycle player correctly answers a question, they return 5 low-energy molecules to the light reactions player in exchange for a carbon atom. This represents the ADP and NADP+ that are returned to the light reactions to be recharged after being used during the Calvin cycle. The number 5 represents the number of ATP and NADPH it took to incorporate each of the 6 carbons into a glucose The light reactions play area features thylakoids stacked molecule (18 ATP and 12 NADPH total for the 6-carbon in formations known as grana. Thylakoids are membrane- glucose). Being a 6-carbon ring, 6 carbons must be bound compartments, and the light reactions happen both earned in order to form glucose. This back-and-forth play within the thylakoid membrane and inside the thylakoid symbolizes the interdependent relationship between the space called the lumen. The light reactions player moves two processes within photosynthesis. freely around and amongst the grana, emphasizing the interconnected nature of the thylakoid grana. Questions to be answered are grouped into two card types: Solo Mission and Team Blast. The Solo The light reactions side also features high-energy Mission cards, answered by the turn taker, explore the molecule spaces, which give the player an extra high- photosynthetic process itself, asking about reactants, energy molecule from the Energy Stash. These molecules products, steps, etc. The Team Blast questions, which represent both ATP and NADPH, which are produced by are answered by both members of a team, feature the light reactions. bigger-picture questions. These ask about the role of photosynthesis in food chains and webs, different The Calvin cycle play area, like the cycle itself, is types of ecosystems, interesting organisms, and plant continuous with no true end or beginning (except the structures, providing context for the process. A third very first and last turn). This side is situated in the stroma group of cards, BioBits, do not feature questions, but of the chloroplast, showing where the cycle actually instead give fun-facts about photosynthesis, plants, occurs. The Calvin cycle player moves around the board, ecology, and other related topics. encountering spaces that allow them to gain a carbon, symbolizing the incorporation of a carbon dioxide

(CO2) molecule, or recycle a carbon, which refers to the regeneration of ribulose-1,5-bisphosphate, RuBP, the molecule that keeps the cycle turning. THE GL FOR LUC Begin O F OS During play, the light reactions player, upon answering GO SE Begin ! a question correctly, passes 3 high-energy molecules C C C M Y C H O CM 6 12 6 to the Calvin cycle, a movement that occurs during MY

CMY photosynthesis as well. Although the high-energy K molecules refer to both ATP and NADPH, the number 3 comes from the 3 ATP produced per 2 water molecules C C hydrolyzed. ATP and NADPH produced during the light reactions then enter the Calvin cycle, powering the LIGHT reactions that convert CO2 into its glucose-precursor REACTIONS glyceraldehyde-3-phosphate, G3P. High-energy molecule C Gain a carbon C Recycle a carbon

Energy Quest 57 Chloroplast Blast: Photosynthesis 5E LESSON PLAN to another. The law of conservation of energy states that energy within a system is neither created nor destroyed—it Engage is just transformed from one type to another. Describe or sketch three simple systems (or project examples from an Arrange students in groups, and give each group a image search): campfire, solar calculator, and a person riding location from the following list. Have them discuss the a bike. Ask students to trace the energy transformations that impact on that location if photosynthetic organisms were happen in each of the scenarios. Do the first one together as to suddenly disappear from Earth this very minute, and an example. choose one main topic to present to the class. • campfire: chemical energy from the burning of the Riverbed (erosion, change shape of the river) wood to heat, light, and sound Rainforest (decreased wildlife due to loss of food, shelter) • solar calculator: light energy to electrical energy (if there Mount Everest or other high mountain (even less oxygen is a battery backup, some light energy is transformed as the elevation increases, increased avalanches) to chemical energy and then back to electrical, or Ocean (less wildlife, less oxygen since photosynthetic if the battery is independent of the solar panel, the organisms in the ocean produce about 50% of oxygen on transformation would be chemical to electrical when no Earth) light energy is available) Desert (less wildlife due to loss of food, shelter) • person riding a bike: chemical energy in muscles to motion energy of pedals to motion of wheels to heat and sound Explore Now ask students to apply the practice of tracing energy Have students complete Investigation B2, Chloroplast transformations to the process of photosynthesis. Explain that Blast. Students will work in teams and play the there are three major energy transfers that you would like Chloroplast Blast game, moving around the light them to find and annotate on their App Maps—two in the reactions and the Calvin cycle and answering questions light reactions, and one in the Calvin cycle: in order to build a glucose molecule. In the light reactions: Faster gameplay: • Light energy is transformed by the photosystems and Completing an entire game will sometimes take more electron transport chain to chemical energy in NADPH. than one class period. Students can take a photo at the • Light energy is also transformed to chemical energy end of class and continue the game later from where in the form of ATP, when hydrogen pumps and water they left off. If you want a round to be completed in one hydrolysis set up a chemical gradient that provides period, here are ways to modify the gameplay to make it energy for the ATP synthase to phosphorylate faster: ADP (some of the chemical energy is converted to • start with 2 or 3 carbon atoms in the glucose molecule energy of motion when the ATP synthase spins as it holder phosphorylates the ADP). • remove Team Blast cards so there is a higher ratio of In the Calvin cycle: BioBit to question cards. • When the energy of NADPH and ATP is used to build glucose (or G3P molecules) from the carbon contained

Explain in CO2 molecules, their chemical energy is transferred to Revisit the key question: How does photosynthesis work, and the glucose/G3P molecules. why is it important? Tracing the energy transformations is a great way to explain how photosynthesis works. Have Elaborate students form the same groups they had the last time they played Chloroplast Blast. List the words electrical, Have students select one BioBit card from the Chloroplast chemical, heat, light, motion, and sound. Explain that these Blast game and research the topic to learn more about it. are different forms of the same property. Forms of what Once students have gathered more information, have them property? The property of energy. Biological and physical create 3 of their own BioBit cards based on their research. systems all around us can be described by how energy in that system is converted or transformed from one form Evaluate After completing the investigation, have students answer the assessment questions on the Evaluate student sheet. 58 B2

Guiding the INVESTIGATION Explore INVESTIGATION B2

Name ______DateDate ______ Introduction to Chloroplast Blast B2 Chloroplast Blast: Photosynthesis Materials: Now that students have explored how ✔ Chloroplast Blast game How does photosynthesis work, and why is it important? board ™ photosynthesis works through the LEARN Photosynthesis uses the sun’s energy, carbon dioxide, and water to make ✔ Player marker tokens sugars. This incredible process is the foundation for nearly every food web on ✔ Carbon atoms, 6 per app, they have an opportunity to apply their Earth! You and your Chloroplast Blast game partner will navigate different team of 2 areas of the chloroplast. As you move around the game board, Solo Mission ✔ Number cube understanding while playing a fun and challenging questions will help you understand how photosynthesis works. Cooperative Team Blast questions will focus on how important the process is to the ✔ Level B card set game. Each board can have 4–6 players: organisms, ecosystems, and biomes of Earth. Your team of two is in a race to ✔ Completed App collect six carbon atoms to build a glucose molecule. Collecting carbon atoms Map from previous will require you to learn and share your understanding of photosynthesis. investigation, 4 players: Students pair up and form 2 teams of 2. Ready, set, CHLOROPLAST BLAST! 1 per student 5 players: The fifth player asks the questions and  Introduction to Chloroplast Blast Chloroplast Blast is played in teams with two players per team. If you have an odd number of players, see the subs in when a stage switch card is drawn. turn-taking instructions in Part 3 for help. 1. Take out your photosynthesis App Map for reference as you become familiar with how the game is 6 players: Students pair up and form 3 teams of 2. played. Once you begin playing the game, however, you will have to pay to use the map for assistance.

2. Decide who your game-playing partner will be.

Be sure each group of players has an B-level card set 3. Study the layout and content of the Chloroplast Blast game board and materials with your partner.

™ (there are separate sets for levels A, B, and C). Review 4. Set aside the LEARN target card(s). Some question cards will direct you to scan a certain target before the Background section for information on the types answering the question. of cards and questions contained in the sets. A list of key words, terms, and concepts covered in the B-level cards can be found in the Topic Tracker at the end of this Teacher Guide section. A Teaching Tip has been included with suggestions on how students might use the Topic Tracker.

B2 Chloroplast Blast: Photosynthesis Allow time for the game groups to work together Copyright © CPO Science Can be duplicated for classroom use 1 of 5 Energy Quest to become familiar with the game board layout

and materials. Students can work in their groups to 181-190_EQ_B2_INV.indd 1 9/27/17 2:00 PM answer the guiding questions, or you can discuss them in a whole-class setting. Make sure all students have their photosynthesis App Map for reference ™ TEACHING TIP throughout the game, and access to the LEARN app. Students might want to refer to the app for help, and they will need it if they come across a card that Card Management The Chloroplast Blast game ™ contains a LEARN logo. card sets are color-coded for level A, B, and C, and App Map CELLULAR RESPIRATION B each individual card also has a level A, B, or C icon

As you monitor the a. n.

4. for quick identification. There might be times when progress of the groups, e-

e- you would like groups in the same class to play the

be sure that everyone + 1. j.

i. game at different levels. There may even be times can identify the high- k. e- m. e- when you let students chose which level they use. g. 2ATP 2. h. l. NAD

and low-energy molecule b. + P FAD To keep leveled sets together without having to + 3. CoA

icons that are shown f.

P look at each individual card, have students hold GDP P

moving from the light CoA NADH + P CoA

e. up their boxes, slightly tilted. You can quickly scan c. NAD d. e- +

reactions to the Calvin + 2ATP 2ATP e-

+ the tops of the cards as they are lined up in the set +NADH +NADH e- cycle and back again. e- to see that they are all the same color. Encourage

Copyright © CPO Science B4 Mighty Mitochondria: Cellular Respiration students to orient the cards in the box so all the Can be duplicated for classroom use Energy Quest fronts and backs face the same way. Also be sure they keep the correct target card with each level.

Energy Quest 59 Chloroplast Blast: Photosynthesis

Guiding the INVESTIGATION Explore INVESTIGATION B2

a. What cellular organelle is featured in this game, and why was this organelle chosen?  Gameplay basics The game takes place inside a chloroplast, which makes sense because this is where photosynthesis occurs. This game has one member of a student team b. Why is the game board divided into an area called “light reactions” and an area called “Calvin cycle”? moving through the light reactions while the other Photosynthesis occurs in two stages: the light reactions, where light energy member of the team moves through the Calvin cycle. is captured and converted to high-energy molecules, and the Calvin cycle, Help students notice that light reactions players can where high-energy molecules are used to make glucose. move in any direction after the first turn, while Calvin c. What is the name of the pancake-stack-like structures in the light reactions area of the board? The pancake-stacks are the grana thylakoids. cycle players move clockwise. d. Why do you suppose there is a glucose molecule shown in the center of the Calvin cycle? Another unique aspect of this game is that the light The Calvin cycle produces glucose, which is the goal of photosynthesis. e. The game board shows something produced in the light reactions that moves from the light reactions to reactions/Calvin cycle partners will be exchanging the Calvin cycle, and is returned by the Calvin cycle to be used again in the light reactions. What is it? high- and low-energy molecule tokens as they work The board shows high-energy molecules leaving the light reactions and entering toward collecting all 6 carbon atoms to build a the Calvin cycle. It also shows those same molecules leaving the Calvin cycle and returning to the light reactions—only in this case, they are low-energy glucose molecule. This exchange of high- and low- instead of high-energy. energy molecule tokens represents how the light  Gameplay basics reactions produce high-energy NADPH and ATP for Object of the game: Be the first team of two players to collect 6 carbon atoms for your glucose molecule holder, use in the Calvin cycle, which returns low-energy advance to the glucose molecule ring, and correctly answer a final question. 1. Work with your partner to determine who will move through the thylakoid stacks of the light reactions NADP+ and ADP for “recharging.” Players must answer and who will move around and around the Calvin cycle. 2. Select a team marker token color. You will each have your own marker token, but they will be the questions correctly to earn the opportunity to do the same color. molecule exchange and receive carbon atoms for the 3. Get a glucose molecule holder card. This is where you and your partner will keep the carbon atoms you earn. Collect all 6 to enter the “GO for the glucose!” ring on the game board. team. Help students notice that one side of the high- 4. Each time it is your turn, you will roll the die, move your token, and take a card. energy molecule token can be used to represent the 5. When you give a correct answer to a question, you earn the right to exchange high-energy molecule (HEM) tokens with your partner, and/or gain a carbon atom for your team’s glucose molecule holder. high-energy state, and the other side can represent 6. The HEM token exchange/carbon-atom-gain process works like this:

TEACHING TIP encountered. Then, you could have them find cards (or create their own) that would complete Using the Topic Tracker The game cards certain categories. allow students to encounter many photosynthesis vocabulary terms as well as ideas and topics that 3. You could give the Topic Tracker to students and demonstrate how photosynthesis impacts daily have them highlight certain terms to look for and life, organisms, and ecosystem dynamics. The Topic check off as they play the game. This makes the Tracker provides these key words in categories. Here list more manageable and allows you to focus on are some ways you could use the Topic Tracker: certain concepts. 4. You can use the Topic Topic Tracker PHOTOSYNTHESIS B 1. Students can check off the words they encounter Ecology Organisms  aphotic/photic zone  root hairs  algae  artificial selection  roots  bacteria Tracker to guide a  autotrophs  seeds  bamboo  biome  spores on the game card they draw on each turn. This  cactus  competition  stem  cyanobacteria  consumer  stoma(ta)  whole-class review of  desert  stroma deciduous trees list can be used for multiple games, and then  domestication  taproot  evergreen  forest floor  thylakoid/thylakoid grana  fern  heterotrophs  xylem  fungi  hydroponics game highlights. For  legume students have a record of which terms they  kleptoplasty Processes  Calvin cycle  lichen  natural selection  gradient  producers  moss  light reactions example: Ask “Who  rainforest  mycorrhizae covered. (This extra game task might be too  photosynthesis  soil  Nepenthes attenboroughii,  phototropism  symbiotic relationship (rat-eating plant)  transpiration remembers answering  tundra  peanut distracting for some students—use with caution.) Chemistry  poison ivy Botany  ADP/ATP  carotenoid  phytoplankton  ATP synthase  cellulose  rodents  carbohydrate a question about  chlorophyll  seaweed  carbon dioxide/CO  chloroplast 2  glucose/C H O  saguaro cactus  cuticles 6 12 6  hydrogen/H  soybean aphids  fruit 2. If students keep the cards that they draw on each  light energy  vascular plants producers? What is a  genome  NADPH/NADP+  leaves  xerophytic groundcover  oxygen/O  membranes 2  phosphate turn, they could go through the checklist at the  mesophyll cells  photons producer? What does  organelle  product  phloem  reactant  photosystems I and II  starch end of the game and mark off the words they  pigment  water/H O it have to do with 2  plasma membrane

Explore INVESTIGATION B2 Explore INVESTIGATION B2

a. When a light reactions (LR) player answers a question correctly, 3 HEM tokens are passed to Calvin If you land on… Light reactions player Calvin cycle player cycle (CC) partner. Unmarked space Draw a card; see the next table for what Draw a card; see the next table for what to b. When a CC player answers a question correctly, 5 tokens (now they are considered to be low-energy to do with each card type. do with each card type. molecules, or LEM) are passed back to LR partner, and a carbon atom is placed on team’s glucose molecule holder card. High-energy molecule space Gain 1 high-energy molecule token from n/a energy stash and take a regular turn. 7. HEM tokens that are traded between team partners are the tokens that belong to them. The only way to gain HEM tokens from the general energy stash is when: Carbon atom recycle space n/a Lose 1 carbon atom from the glucose molecule holder and take a regular turn. • a LR player lands on a special HEM board space • a CC player gets an answer correct but doesn’t have enough HEM tokens to trade in for a carbon atom Free carbon atom space n/a Gain 1 carbon atom from the glucose molecule holder and take a regular turn. • a CC player passes the “begin” space in the Calvin cycle. Occupied space Invader (new to the occupied space) draws until they reach a Solo Mission or Team • a BioBit card with a positive result is selected by a LR player Blast question card. Both players have a chance to write down the answer. Correct answers receive 2 high-energy molecule tokens from the energy stash. No penalty for wrong answers. Invader ROLLS AGAIN AND TAKES ANOTHER TURN.  Chloroplast Blast rules This game has teams of two playing against one another, instead of the individual play featured by most games (including the next game, Mighty Mitochondria). This might seem a little confusing at first, but once you study If you draw a… Light reactions player Calvin cycle player the rules and take a few turns, you will catch on quickly. Solo Mission card: Answer Correct answer: Pass up to 3 high-energy Correct answer: Return 5 low-energy Turn-taking: All light reactions players take their turns first, and then Calvin cycle players take their turns in the question on your own. molecule tokens* to Calvin cycle partner; molecule tokens to light reactions partner the same order as their light reactions partners. If there are three or five players, the odd player can ask the your turn is over. and gain a carbon atom for the glucose Incorrect answer: Turn is over. molecule holder. If unable to gain a carbon questions and this position can rotate into a team (and a current team member take the odd position) whenever *If you have no high-energy molecule tokens, (4 or fewer high-energy molecule tokens), a “stage switch” card is drawn. your turn is over. gain 1 high-energy molecule token from the energy stash. Your turn is then over. Light Reactions Players Incorrect answer: Your turn is over. 1. Start with 5 high-energy molecules. Team Blast card: Collaborate Correct answer: Light reactions player passes 3 high-energy molecule tokens* to Calvin with partner to answer cycle partner, and Calvin cycle player trades 5 high-energy molecule tokens for carbon 2. Go to the begin space in light reactions. Roll the number cube, move the token, and draw a card. You may question. if possible. choose your own path until your team enters the glucose molecule ring inside the Calvin cycle. If, on any Incorrect answer: Your turn is over. turn, you draw a Solo Mission or Team Blast card, and you do not have any high-energy molecules, your *If light reaction player has no high-energy molecule tokens, your turn is over. turn is over. BioBit card Follow instructions on card. 3. Consult the summary tables that follow for information on special board spaces, cards, scoring, and how to get help. How to win: When your team earns 6 carbon atoms for the glucose molecule holder, move to the “GO for the Calvin Cycle Players Glucose!” ring on your next turn and collaborate on the first question you draw. You must answer correctly to win, or wait in the ring until your next team turn and try again. If you do not have time in one class period to 1. Go to the begin space in the Calvin cycle. Roll the number cube and land on a space. Draw a card and finish the game, make a note of where you are on the board, how many HEM tokens you have, and how many answer the question. Continue to move clockwise around and around the cycle until your team enters carbon atoms your team has so you can continue the game later. Better yet, just take a photo! the glucose molecule ring. How to get help: For any given question, you can spend 1 high-energy molecule token for a look at your 2. Each time you pass the begin space, take 1 high-energy molecule token from the energy stash. ™ photosynthesis App Map, or to consult the LEARN App. 3. Consult the summary tables that follow for information on special board spaces, cards, scoring, and Review: Take a couple of minutes to look at examples of the three types of cards that can be drawn on any how to get help. given turn. Review the summary tables to see what happens once questions are answered.

B2 Chloroplast Blast: Photosynthesis Copyright © CPO Science B2 Chloroplast Blast: Photosynthesis Copyright © CPO Science Can be duplicated for classroom use 3 of 5 Energy Quest Can be duplicated for classroom use 4 of 5 Energy Quest

Guiding the INVESTIGATION TEACHING TIP House Rules There are lots of opportunities for  Chloroplast Blast rules you and/or your students to add, delete, or modify Have students read through all rules and summary rules to speed up, or slow down, increase or decrease tables. Make sure students pull examples out of the the challenge level, or just to add more fun. Here are deck for Solo Mission, Team Blast, and BioBit cards so some “house rules” you might want to try, or have they can differentiate between the front and the back each group come up with their own modification! of the cards, and how to orient them in the box so when • For level A and B students, have the next-level set the question is drawn, the player cannot see the answer. available so students decide on each turn what level Roleplay a few turns for the class, so they can see how card they want to draw. Correct answers for a level the turn-taking order works, and what to do when a up earn additional high-energy molecule tokens. question is answered correctly or incorrectly. Review • Students keep cards that they answer incorrectly. what to do if a player lands on an occupied space. End the game early enough so that students have New players will always need to refer to the summary 5–10 minutes to review the cards they answered tables as they play, but once you have played one incorrectly, ask questions, or make notes. round of the game, the rules and gameplay action • The teacher calls out “stage switch” a couple of become familiar and easy to remember. times during a game round, causing all partners in the class to switch to the other stage. Energy Quest 61 Chloroplast Blast: Photosynthesis

Explore INVESTIGATION B2 ADDRESSING MISCONCEPTIONS  GO for the glucose! Misconception: Photosynthesis produces energy. Place your player marker tokens on the board, hand out 5 high-energy molecule tokens to each light reactions player, and GO for the glucose! Photosynthesis uses light energy to produce  Stop and think glucose—or more specifically, to produce 3-carbon a. The high and low-energy molecule tokens traded back and forth between light reactions players and their Calvin cycle partners represent ATP/ADP and NADPH/NADP+. Which of these molecules is an electron molecules, glyceraldehyde 3-phosphate, which are carrier, and which carries energy in the form of a high-energy chemical bond? The electron carrier is NADPH. The molecule that carries energy in its high- combined to make a 6-carbon molecule of glucose. energy phosphate bond is ATP. Glucose is not energy. Glucose is used as energy b. Why can carbon atoms only be gained and lost in the Calvin cycle portion of the game board, and not in storage in plants, and energy is released during the light reactions area? Carbon atoms can be gained and lost only in the Calvin cycle, because this is cellular respiration. Alternatively, glucose can itself where the glucose is built from carbon atoms. The light reactions stage captures be used in the following ways: the light energy and produces high-energy molecules for the Calvin cycle—the light reactions do not produce glucose directly. It can be…

c. What are the two other kinds of atoms, besides carbon, that make up a glucose molecule? Why is carbon treated as more important? • stored as large starch molecules for later use Glucose contains hydrogen and oxygen atoms in addition to carbon atoms. Carbon has the ability to bond with up to four other atoms when it forms • synthesized into the highly soluble sucrose for molecules, whereas hydrogen can only bond with one other atom, and oxygen usually only with two. This makes carbon versatile—it is the backbone transportation to other parts of the plant of biomolecules like glucose. Notice how it is the carbon atoms that are responsible for the ring-like structure of the glucose molecule. • turned into cellulose for structure

d. What is one new thing that you learned about photosynthesis, plants, or ecology by playing this game? Answers will vary. A class discussion of answers might be helpful. Note: It is true that the light reactions produce energy in the form of ATP, but that chemical potential energy is used in the Calvin cycle to produce the G3P molecules. The overall product of

Copyright © CPO Science B2 Chloroplast Blast: Photosynthesis photosynthesis, then, is glucose (not ATP or energy). Can be duplicated for classroom use 5 of 5 Energy Quest Misconception: Photosynthesis requires a green plant.

Most organisms that perform photosynthesis are green, because the main photosynthetic Guiding the INVESTIGATION pigment, chlorophyll, reflects some green light. All plants, algae, and cyanobacteria that perform  GO for the glucose! photosynthesis have chlorophyll. There are, however, organisms that perform photosynthesis Students may not have enough time on the first day that are not green. Blue-green cyanobacteria, red of gameplay to collect all 6 carbon atoms to build a algae, and brown algae are examples of non-green glucose molecule. As you monitor group progress, you organisms that perform photosynthesis. They do might want to announce that only 3 carbon atoms will contain chlorophyll, but they also contain accessory be needed before a team can advance to the glucose pigments such as carotenoids and phycobilins that molecule ring. This is a great time to point out that the mask the green color. Photosynthesis does not Calvin cycle actually produces 3-carbon molecules, require a green plant. glyceraldehyde 3-phosphate (G3P), which are later combined to form 6-carbon glucose.

If you want students to continue the game on another day, have them make a note on their investigation page of their space number and the number of high-energy molecules they have, as well as how many carbon atoms their team has.

62 B2

Evaluate INVESTIGATION B2 Evaluate INVESTIGATION B2

Name ______Date ______Name ______Date ______

Congratulations! You are well on your way to becoming a photosynthesis expert. Study this experiment and A 5 centimeter piece of aquatic plant is placed into containers 1 and 2, and each plant is completely submerged answer the questions to show what you know. in the solution. Containers 2 and 4 are wrapped with aluminum foil. All four containers are placed in front of a light source for 50 minutes. How can you tell that photosynthesis is happening when you can’t actually see the process? Bromothymol blue is an indicator that can show the presence of carbon dioxide. The solution is blue, but in the presence of carbon dioxide, it turns yellow.

1. You insert a straw into a container of bromothymol blue and gently blow bubbles into the solution. What color will bromothymol blue turn when you blow bubbles of exhaled air into the solution? Why? The color will turn yellow, because exhaled air contains carbon dioxide, and bromothymol blue turns yellow when carbon dioxide is added to it. 4. Will photosynthesis occur in any of the containers? If so, which ones, and why? 2. Suppose the carbon dioxide was removed, or used up. What color would the solution be then? Why? Photosynthesis should occur in container 1. Photosynthesis needs a plant with When the carbon dioxide is removed, the solution should turn back to a blue color. photosynthetic pigments, like chlorophyll, carbon dioxide, and water. Container 3. Next, you pour 25 mL of bromothymol blue into each of four containers. IMPORTANT NOTE: The 1 has all of these things. Photosynthesis won’t occur in the other containers. bromothymol blue solution has been saturated by bubbles of exhaled air. What color should the solution be? Why? Container 2 is missing the light energy because it is blocked by the aluminum The solution will be yellow, because it is saturated with carbon dioxide. foil. Container 3 has no plant, and container 4 has no plant or light energy.

Copyright © CPO Science B2 Chloroplast Blast: Photosynthesis Copyright © CPO Science B2 Chloroplast Blast: Photosynthesis Can be duplicated for classroom use Energy Quest Can be duplicated for classroom use Energy Quest

WRAPPING UP

Have your students reflect on what they learned from the investigation by answering the following questions: 1. What are the two stages of photosynthesis? 2. How are the two stages of photosynthesis dependent upon one another? 3. What is the ultimate goal of each stage?

Energy Quest 63 Chloroplast Blast: Photosynthesis

Notes and Reflections Evaluate INVESTIGATION B2

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5. Which containers serve as the control group? Explain why this is important to the experiment. Containers 3 and 4 are the control group. To better observe evidence of photosynthesis, you need to compare it to setups that you know for sure will not conduct photosynthesis.

6. Would the presence of plants in the container cause the carbon dioxide level to increase, decrease, or stay the same? Explain. Photosynthesis uses carbon dioxide, so the carbon dioxide level in the containers in which photosynthesis occurs should decrease.

7. You unwrap each container, carefully remove the plants from containers 1 and 2, and observe the final color of the solutions. What is the final color of the solution in containers 1 and 2, and why? Use the table to record your answers to this question. The control group data is completed for you.

Container Initial color Final color Why? Container Initial color Final color Why? 1 yellow blue Photosynthesis occurs and uses the 1 yellow blue Photosynthesiscarbon dioxide, occurs so and the uses bromothymol the carbon dioxide, blue so the bromothymol blue turns back to a blue color. turns back to a blue color. 2 yellowyellow yellowyellow PhotosynthesisPhotosynthesis cannot cannot occur, so occur, the carbon so the dioxide level does not increase, and the solution stayscarbon yellow. dioxide level does not decrease, and the solutions stays yellow. 3 yellow yellow 3 yellow yellow ThereThere is no is photosynthesis,no photosynthesis, so the carbon so the dioxide car- levelbon stays dioxide constant, level and stays the solution constant stays and yellow. the solution stays yellow. 4 yellow yellow 4 yellow yellow ThereThere is no is photosynthesis,no photosynthesis, so the carbon so the dioxide car- level stays constant, and the solution stays yellow. bon dioxide level stays constant and the solution stays yellow.

8. Do plants use carbon dioxide at night? Does this experiment answer that question? Plants do not use carbon dioxide at night, because photosynthesis, the process that uses carbon dioxide, does not occur when there is no light energy available. Container 3 simulates a plant in darkness—and the carbon dioxide level did not decrease. This supports my statement that plants do not use carbon dioxide at night.