PHOTOSYNTHESIS UNIT PACKET

Transcription

1 This packet contains all of the papers you will need for the next week of class. You will be turning it in at the end of every class period, and picking it up in the beginning of class. Name: Class Period: PHOTOSYNTHESIS UNIT PACKET

2 4/26 Do Now! - Where do trees get most of their mass? - Why do you think that? Read Today s Learning Targets: I will be able to carry out an investigation and construct my own explanation for the results. I will be able to predict, observe, and explain the relationship between carbon dioxide and plants. I will be able to listen to classmates and share scientific ideas while engaged in inquiry. I will be able engage in scientific discourse to explain the relationship between carbon dioxide and plants.

3 Part 1. Photosynthesis in Leaf Discs POE You will be doing this experiment with your groupmates. Everybody is expected to participate and contribute. ---But--- you should be answering the PREDICT and EXPLAIN questions on the analysis page individually. (You can work together on the OBSERVE portion) Materials: - Sodium Bicarbonate solution - Liquid dish soap - Eyedropper - Plastic syringe - Plastic straw - Spinach leaves - Hole punch - 1 large beaker - 1 small beaker or plastic cup - Timer - Light source - Paper towels Procedure: Solutions are safe to handle without gloves. Wear Goggles! Read all instructions and answer the PREDICT questions BEFORE starting the lab. 1. Using a one-hole punch, cut 20 leaf disks from young actively growing leaves. 2. Remove the plunger from a large clean syringe. Place 20 leaf disks into the body of the syringe. Be sure the leaf disks are near the tip of the syringe as you reinsert the plunger so as not to damage the disks.

4 3. Insert the tip of the syringe into a beaker of sodium bicarbonate solution and fill it about onethird full. 4. Hold the syringe tip upward and expel the air by depressing the plunger carefully. Stop before solution comes out the tip. 5. Seal the tip of the syringe using the index finger of your left hand and hold tightly. Pull back on the plunger creating a partial vacuum within the syringe. If you have a good seal it should be hard to pull on the plunger and you should see bubbles coming from the edge of the leaf disks. Hold for a count of ten. 6. Simultaneously, release your index finger and the plunger. Some of the leaf disks should start to sink. Tap the side of the tube or shake gently to break any bubbles on the edges of the disks. 7. Repeat steps 5 and 7 until all the disks sink. Do not overdo these steps!! You have been successful if the disks sink to the bottom. Don't repeat "just to be sure" as it is possible to damage the cells of the leaves. 8. Remove the plunger from the syringe and pour the solution containing the disks into 2 plastic cups or beakers and add the remainder of your solution equally to both beakers. There should be 10 disks per cup. Make sure they sink to the bottom. 9. Place the beaker under a light source, approximately 6-8 inches below the light. The lights are best held in a clamp on a ring stand. Begin timing the experiment as soon as the light is turned on. Record your observations in the OBSERVE portion of the lab analysis page. 10. Notice what is happening to the leaf disks as photosynthesis proceeds. Continue to record your observations the OBSERVE portion of the lab analysis page. After each time check, tap the side of the beaker to make sure the disks are not sticking to the container walls. 11. When instructed, clean the lab equipment and dispose of solutions in the sink drains.

5 Leaf Disk Analysis Questions (POE) PREDICT 1. What are the bubbles that you saw forming on the edges of the leaf disks when they were in the syringe? 2. What do you think is going to happen when you put the leaf disks under the light source? Why will that happen? (If you do not know, make an educated guess; think of this as a pre-test) 3. What do you think would happen if you didn t put the leaves under a light source? Why would that happen? OBSERVE 1. Diagram what is happening to the leaf disks? (Don t forget to use labels and color!!!) 0 Minutes 8 Minutes 15 Minutes

6 Time (Minutes) Observations Explain 1. What changes occurred throughout the experiment? Why did that occur? 2. How does what happened relate to photosynthesis? Pause for Instructions: 3. How have your answers to Explain 1 and 2 changed after talking to your groupmates?

7 Day 1 Extension: In the video, we learned that trees (and plants) get their mass from carbon dioxide. However, we never learned how scientists figured out that it is not water. Design an experiment that we could do to determine how much mass plants gain from water. ***Hint: You will likely need to do a lot of measuring*** Please include a general outline of your procedure and your rationale for why that would help solve this problem. Use this area to write the outline of your experimental procedure: How will this experiment help us to determine how much mass plants receive from water?

8 4/26 Exit Ticket (2 pages) Use the following scale to assess if you met today s learning targets: Score: Not Yet Met the target Rocked it! Score: 1. I will be able to carry out an investigation and construct my own explanation for the results. Evidence: Score: 2. I will be able to predict, observe, and explain the relationship between carbon dioxide and plants. Evidence:

9 Score: Not Yet Met the target Rocked it! Score: 3. I will be able to listen to classmates and share scientific ideas while engaged in inquiry. Evidence: 4. I will be able engage in scientific discourse to explain the relationship between carbon dioxide and plants. Score: Evidence:

10 4/27 Do Now! - What are some factors that would affect a plant s rate of photosynthesis? - Define input and output Read Today s Learning Targets: I will be able to design an experiment which models the process of photosynthesis I will be able to conduct an experiment and record data I will be able to investigate how the manipulation of input or output factors influence the rate at which photosynthesis occurs I will be able to listen to classmates and share scientific ideas while engaged in inquiry I will be able to engage in scientific discourse in order to discuss the design and implementation of my experiments I will be able to record experimental data

11 Photosynthesis Reading Oxygen - the oxygen that we breathe - is just a waste product of plants! Every split second that sunlight hits that leaf, photosynthesis is initiated, bringing energy into the ecosystem. It could be said that this is one of the most important - if not the absolutely most important - biochemical reaction. And it all starts with the leaf.

12 What can a tiny plant do that you can't do? This tiny plant can use the energy of the sun to make its own food. You can't make food by just sitting in the sun. Plants are not the only organisms that can get energy from the sun, however. Some protists, such as algae, and some bacteria can also use the energy of the sun to make their own food. What is Photosynthesis? If a plant gets hungry, it cannot walk to a local restaurant and buy a slice of pizza. So, how does a plant get the food it needs to survive? Plants are producers, which means they are able to make, or produce, their own food. They also produce the "food" for other organisms. Plants are also autotrophs. Autotrophs are the organisms that collect the energy from the sun and turn it into organic compounds. So once again, how does a plant get the food it needs to survive?

13 Through photosynthesis. Photosynthesis is the process plants use to make their own food from the sun's energy, carbon dioxide, and water. During photosynthesis, carbon dioxide and water combine with solar energy to create glucose, a carbohydrate (C 6 H 12 O 6 ), and oxygen. The process can be summarized as: Sunlight, carbon dioxide + water glucose + oxygen. The overall chemical equation for photosynthesis is: Light Energy + 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2 Glucose is a sugar that acts as the "food" source for plants. The oxygen formed during photosynthesis, which is necessary for animal life, is essentially a waste product of the photosynthesis process. Photosynthesis changes light energy to chemical energy. The chemical energy is stored in the bonds of glucose molecules. Glucose, in turn, is used for energy by the cells of almost all living things. Photosynthetic organisms such as plants make their own glucose. Other organisms get glucose by consuming plants (or organisms that consume plants). Actually, almost all organisms obtain their energy from photosynthetic organisms. For example, if a bird eats a caterpillar, then the bird gets the energy that the caterpillar gets from the plants it eats. So the bird indirectly gets energy that began with the glucose formed through photosynthesis. Therefore, the process of photosynthesis is central to sustaining life on Earth. In eukaryotic organisms, photosynthesis occurs in chloroplasts. Only cells with chloroplasts plant cells and algal (protist) cells can perform photosynthesis. Animal cells and fungal cells do not have chloroplasts and, therefore, cannot photosynthesize. That is why these organisms rely on other organisms to obtain their energy. These organisms are heterotrophs.

14 Photosynthesis Reading Review: 1. Where does the energy for photosynthesis come from? 1. How is the process of photosynthesis central to sustaining life on Earth? 2. What are the two products produced by photosynthesis? 3. What two raw materials are needed by plants in order to perform photosynthesis? 4. After reading this article, what is your new (or improved) explanation of what happened in the leaf disk experiment yesterday?

15 Photosynthesis in Leaf Disk Introduction: Photosynthesis is a process in which plants convert light energy (sunlight) into usable chemical energy (carbohydrates). Photosynthesis involves two simultaneous processes: the light dependent reactions and the light independent reactions (Calvin Cycle). In the light dependent reactions, light energy is captured and converted to high energy ATP and NADPH molecules. In the light independent reactions these high-energy molecules are used to reduce CO 2 and eventually form carbohydrates such as glucose. Overall reaction (unbalanced): Light energy + CO 2 + H 2 O C 6 H 12 O 6 + O 2 In this experiment, the spaces in the spongy mesophyll of leaf disks are filled with a sodium bicarbonate solution, which causes them to sink in the solution. The leaf disks are then exposed to light and observations are made as the cells undergo photosynthesis. Using the experiment we did yesterday as your experimental control condition, you will be designing an experiment which investigates how modifying one of the inputs of photosynthesis (CO 2, H 2 O, or light) influences the rate of photosynthesis that occurs. How this modification occurs is up to you, but some of the many possibilities are that you can increase/decrease the presence, modify it in some way, change where photosynthesis is occurring, etc. I need to check your procedure off before you get started. Write in pencil in case modifications need to be made. Materials: - Sodium Bicarbonate solution - Liquid dish soap - Eyedropper - Plastic syringe - Plastic straw - Spinach leaves - Hole punch - 1 large beaker - 1 small beaker or plastic cup - Timer - Light source - Paper towels

16 Question: What is the effect of (MV) on the rate of photosynthesis occurring in plants(rv) Hypothesis: If (MV) then (RV) because (based on knowledge of photosynthesis) Diagram: Use this space for a labeled diagram to support the procedure Procedure: Use the procedure from yesterday as a guide!!! The procedure from yesterday should be your experimental control condition, so the new parts should be related to your manipulated variable

17 Ms. Schmidt s Stamp of Approval

18 Data Table: Title: Time (Minutes) Number of Floating Disks (Control condition) Number of Floating Disks ( Your Manipulated Variable) *Please send somebody up to give me your control condition data Errors/Design Improvements : This is space to record any errors that may have occurred in your experiment today or any ways that you would improve the procedure you created.

19 Day 2 Extension: Conduct two more trials of your experiment. These can be done at the same time. Data Table: Time (Minutes) Trial 2 Trial 3 Number of Number of Floating Floating Disks ( Your Disks Manipulated (Control Variable) condition) Number of Floating Disks (Control condition) Number of Floating Disks ( Your Manipulated Variable) Extension Question: Why is it important to do multiple trials in an experiment? Were there any differences in the data between the different trials?

20 4/27 Exit Ticket (2 pages) Use the following scale to assess if you met today s learning targets: Score: Not Yet Met the target Rocked it! Score: 1. I will be able to design an experiment which models the process of photosynthesis Evidence: Score: 2. I will be able to conduct an experiment and record data Evidence:

21 3. I will be able to investigate how the manipulation of input or output factors influence the rate at which photosynthesis occurs Score: Evidence: 4. I will be able to listen to classmates and share scientific ideas while engaged in inquiry. Score: Evidence: Score 5. I will be able to engage in scientific discourse in order to discuss the design and implementation of my experiments Evidence: Score: 6. I will be able to record experimental data Evidence:

22 4/28 Do Now! - What do you use a line graph for? Bar graph? - What are important things to include when graphing? Read Today s Learning Targets: I will be able to create a graphical representation the data collected during my photosynthesis investigation I will be able to analyze and evaluate the data I collected from my photosynthesis model I will be able to explain how manipulating the inputs affects the rate of photosynthesis I will be able to listen to classmates and share scientific ideas to evaluate the effectiveness of our model I will be able to engage in scientific discourse to determine patterns between different sets of experimental data I will be able to graph my experimental data

23 Results: You will be responsible for: - Graphing your data from yesterday o Your graph needs to be titled and labeled - Copying down the graph of the entire class s control condition data o Explaining any patterns or differences between your data and the class data. o Explaining what might have caused these patterns/differences. Your Data:

24 Class Data

25 What similarities or differences, do you see within the class data? (Example: I noticed that at 20 minutes, everybody s data showed that no leaf disks were floating -or- I noticed that at 20 minutes, only one group s leaf disks were floating. - This answer should fill the entire box (use multiple examples) What similarities or differences, did you see between your data and the class data? ( Remember we are only looking at the experimental control data) What do you think caused these patterns (similarities or differences) in the data?

26 Conclusion: Instead of writing out a conclusion, you will be creating poster presentations for a gallery walk in class Monday. Within these presentations you will be responsible for: - Explaining what photosynthesis is - Answering your group s investigative question - Analyzing your data - Explaining the similarities or differences between your data and the class data - Speaking like a scientist. Read the rubric for more detail on exactly how I want you to do this. CATEGORY Exceeding Meeting Approaching Beginning Explanation of what photosynthesis is. Meeting The presentation includes an additional, highly creative way to model photosynthesis. The poster has an accurate explanation of photosynthesis -andthe explanation includes the formula for photosynthesis The poster has one of the following: an accurate explanation of photosynthesis -orthe formula for photosynthesis The explanation in incorrect or incomplete. Answer to the investigative question Meeting Includes suggestions for improving the design of the experiment. The poster answers the investigative question, and includes the experimental data as evidence. The poster answers the investigative question, but does not include experimental data. The poster does not answer the investigative question. Data Analysis Meeting Discusses the accuracy and validity of the data. A graph of the experimental data is included, labeled, and explained in words. A graph of the experimental data is included, but is either not labeled or not explained in words. The graph of the experimental data is drawn incorrectly, or is not explained. Patterns or differences in class data. Meeting The explanation includes reasoning for why those differences might exist. The poster has a section which correctly identifies patterns or differences between their experimental control, and the class s control data. The poster identifies patterns or differences in the class data, but does not compare it to their group s data. The poster does not identify any patterns or differences. Discourse Meeting Students have a section that anticipates and answers peer questions. All group members present equally Presenters attempt to answer the questions asked by their peers. One group member does most of the talking, -or- Presenters do not answer peer questions. One group member does not participate in the presentation.

27 Day 3 Extension: Create a new and exciting way to demonstrate your knowledge of photosynthesis. How you do this is up to you, but I am looking for creativity. You will be including this in your Gallery walk presentation tomorrow. Some possible ideas are a skit, a song, a diagram, etc. You are not limited one of these, I just want you to show me your learning.

28 4/28 Exit Ticket (2 pages) Use the following scale to assess if you met today s learning targets: Score: Not Yet Met the target Rocked it! Score: 1. I will be able to create a graphical representation the data collected during my photosynthesis investigation Evidence: Score: 2. I will be able to analyze and evaluate the data I collected from my photosynthesis model Evidence:

29 3. I will be able to explain how manipulating the inputs affects the rate of photosynthesis Score: Evidence: 4. I will be able to listen to classmates and share scientific ideas to evaluate the effectiveness of our model. Score: Evidence: Score 5. I will be able to engage in scientific discourse to determine patterns between different sets of experimental data. Evidence: Score: 6. I will be able to graph my experimental data.

30 Evidence: 5/2 Do Now! Please read the following information to prepare for the gallery walk: Today you will be presenting your poster in a gallery walk. During the time you are not presenting, you will be walking around and grading your peers using the presentation syllabus. Guidelines for the gallery walk (as an observer): - You must go to every station, but you only need to grade at least two groups. - During this time you will be responsible for asking the groups you grade a question about their experiment. These questions can be about their experimental design, their results, their interpretation of their results, or any other topic that you think is relevant to their presentation. - Be respectful when listening to your classmates Guidelines as a presenter: - Remember that everybody in your group must participate equally - You must present every part of your poster; it is not enough to have it included but not talked about. - HAVE FUN!

31 Group 1 Names CATEGORY Exceeding Meeting Approaching Beginning Explanation of what photosynthesis is. Meeting The presentation includes an additional, highly creative way to model photosynthesis. The poster has an accurate explanation of photosynthesis -andthe explanation includes the formula for photosynthesis The poster has one of the following: an accurate explanation of photosynthesis -orthe formula for photosynthesis The explanation in incorrect or incomplete. Answer to the investigative question. Meeting Includes suggestions for improving the design the experiment. The poster answers the investigative question, and includes the experimental data as evidence. The poster answers the investigative question, but does not include experimental data. The poster does not answer the investigative question. Data Analysis Meeting Discusses the accuracy and validity of the data. A graph of the experimental data is included, labeled, and explained in words. A graph of the experimental data is included, but is either not labeled or not explained in words. The graph of the experimental data is drawn incorrectly, or is not explained. Patterns or differences in class data. Meeting The explanation includes reasoning for why those differences might exist. The poster has a section which correctly identifies patterns or differences between their experimental control, and the class s control data. The poster identifies patterns or differences in the class data, but does not compare it to their group s data. The poster does not identify any patterns or differences. Discourse Meeting Students have a section that anticipates and answers peer questions. All group members present equally Presenters attempt to answer the questions asked by their peers. One group member does most of the talking, -or- Presenters do not answer peer questions. One group member does not participate in the presentation.

32 Group 2 Names CATEGORY Exceeding Meeting Approaching Beginning Explanation of what photosynthesis is. Meeting The presentation includes an additional, highly creative way to model photosynthesis. The poster has an accurate explanation of photosynthesis -andthe explanation includes the formula for photosynthesis The poster has one of the following: an accurate explanation of photosynthesis -orthe formula for photosynthesis The explanation in incorrect or incomplete. Answer to the investigative question. Meeting Includes suggestions for improving the design the experiment. The poster answers the investigative question, and includes the experimental data as evidence. The poster answers the investigative question, but does not include experimental data. The poster does not answer the investigative question. Data Analysis Meeting Discusses the accuracy and validity of the data. A graph of the experimental data is included, labeled, and explained in words. A graph of the experimental data is included, but is either not labeled or not explained in words. The graph of the experimental data is drawn incorrectly, or is not explained. Patterns or differences in class data. Meeting The explanation includes reasoning for why those differences might exist. The poster has a section which correctly identifies patterns or differences between their experimental control, and the class s control data. The poster identifies patterns or differences in the class data, but does not compare it to their group s data. The poster does not identify any patterns or differences. Discourse Meeting Students have a section that anticipates and answers peer questions. All group members present equally Presenters attempt to answer the questions asked by their peers. One group member does most of the talking, -or- Presenters do not answer peer questions. One group member does not participate in the presentation.

33 5/2 Exit Ticket Peer Evaluation Directions This paper is meant for you to grade your group members based on their and your participation in the project. You will grade them on a scale of 1-10 with 1 being strongly disagree and 10 strongly agree. Self I participated as a cooperative group member I did most of the work for the group I did none of the work for the group Group Member He/She participated as a cooperative group member He/She did most of the work for the group He/She did none of the work for the group Group Member He/She participated as a cooperative group member He/She did most of the work for the group He/She did none of the work for the group

34 Group Member He/She participated as a cooperative group member He/She did most of the work for the group He/She did none of the work for the group Other thoughts or comments you would like Ms. Schmidt to consider.