Planning two investigations to show that plants use carbon dioxide and release oxygen during photosynthesis using videos, including what materials you will need, what data you will collect, and what procedures to follow
Investigation 1: Testing Photosynthesis in a Closed System
Materials needed:
1. Two identical potted plants
2. Two clear airtight containers (such as glass jars or plastic bags)
3. Light source (such as a lamp or sunlight)
4. Carbon dioxide (CO2) source (such as dry ice or baking soda and vinegar)
5. pH indicator solution
6. Video recording device
7. Stopwatch or timer
8. Data table or log sheet
Procedure:
1. Place one plant in each clear container.
2. Seal the containers, ensuring they are airtight.
3. Set up the light source to provide consistent light intensity for both plants. Ensure all other environmental conditions (temperature, humidity, etc.) are equal.
4. Start the video recording device to capture the entire experiment.
5. Introduce the carbon dioxide source into one of the containers while carefully avoiding contact with the plants. In case of using dry ice, place it a safe distance from the plants.
6. Observe the plants for a set period (e.g., 30 minutes) and record any visible changes.
7. Take periodic measurements of the pH levels of the air inside each container, using the pH indicator solution.
8. Continue the observation for a predetermined duration (e.g., 2-4 hours)
9. After the observation period, stop the video recording.
10. Analyze the video footage to document any visible changes in the plants, such as leaf movement or changes in color.
11. Record the pH level measurements from each container at regular intervals.
12. Compile the data collected into a table, indicating the time, pH level, and any visible changes observed.
13. Analyze the data to determine outcomes supporting the release of oxygen via photosynthesis by the plant in the container where the CO2 source was introduced.
Investigation 2: Demonstrating Oxygen Production via Photosynthesis
Materials needed:
1. Elodea or any other aquatic plant
2. Sodium bicarbonate (baking soda)
3. Water
4. Beaker or glass container
5. Light source (such as a lamp or sunlight)
6. Video recording device
7. Stopwatch or timer
8. Data table or log sheet
Procedure:
1. Fill the beaker or glass container with water.
2. Dissolve a small amount of sodium bicarbonate in the water to provide a source of carbon dioxide.
3. Place the Elodea or other aquatic plant into the water.
4. Set up the light source to provide consistent light intensity for the plant.
5. Start the video recording device to capture the entire experiment.
6. Observe the plant for a predetermined duration (e.g., 1 hour) and record any visible changes.
7. Observe the bubble formation on the plant, which represents oxygen release.
8. Continue the observation for the determined duration.
9. After the observation period, stop the video recording.
10. Analyze the video footage to document any visible changes in the plant, primarily focusing on bubble formation.
11. Record the data on the number of bubbles observed during specific time intervals.
12. Compile the data collected into a table, indicating the time and the number of bubbles observed.
13. Analyze the data to determine outcomes supporting the release of oxygen via photosynthesis by the aquatic plant.
Note: In both investigations, be sure to use proper safety precautions and follow ethical considerations, such as not subjecting the plants to excessively long durations without adequate light or removing excess carbon dioxide when the investigation concludes.
Investigation 1: Carbon Dioxide Consumption
Materials:
1. Two potted plants (preferably of similar size and type)
2. Two transparent containers (e.g., glass jars or clear plastic bags)
3. Carbon dioxide source (e.g., baking soda and vinegar solution)
4. Measuring cup
5. Stopwatch or timer
6. Video recording device
Procedure:
1. Set up two identical containers, one for each plant. Ensure that they are transparent and big enough to accommodate each plant.
2. Prepare the carbon dioxide source by mixing vinegar and baking soda in a measuring cup. This will generate carbon dioxide gas.
3. Place one plant inside each container, making sure they are positioned securely.
4. Start recording the video.
5. Introduce the carbon dioxide gas into one of the containers by pouring the carbon dioxide source into that container. Seal it immediately to prevent gas from escaping.
6. Allow the plants to be exposed to light for a specific duration, which could be 2-3 hours.
7. Observe and record any changes in the two plants during the experiment, especially focusing on signs of photosynthesis, such as color changes, oxygen release, or oxygen bubbles being produced.
8. At the end of the experiment, stop the recording.
Data:
1. Time duration of the experiment.
2. Notable changes observed in each plant (e.g., color changes, oxygen bubbles, growth-related changes).
3. Any contrasting differences between the two plants (e.g., if one shows more signs of photosynthesis than the other).
Investigation 2: Oxygen Release
Materials:
1. Two potted plants (preferably of similar size and type)
2. Two transparent containers (e.g., glass jars or clear plastic bags)
3. Water
4. Straw or rubber tubing
5. Beaker or bowl
6. Candle
7. Match or lighter
8. Stopwatch or timer
9. Video recording device
Procedure:
1. Set up two identical containers, one for each plant. Ensure that they are transparent and big enough to accommodate each plant.
2. Fill the beaker or bowl with water.
3. Attach one end of the straw or rubber tubing to the container for plant A and position the other end inside the beaker or bowl filled with water.
4. Insert a lit candle into the container for plant B and place it close to the plant but without touching it.
5. Start recording the video.
6. Allow the plants to be exposed to light for a specific duration, which could be 2-3 hours.
7. Observe and record any changes in the two plants during the experiment, especially focusing on signs of photosynthesis, such as oxygen release.
8. At the end of the experiment, stop the recording.
Data:
1. Time duration of the experiment.
2. Notable changes observed in each plant (e.g., oxygen release, growth-related changes).
3. Any contrasting differences between the two plants (e.g., if one shows more signs of photosynthesis than the other).
Remember, in both investigations, it is essential to discuss your findings and compare the results obtained from the different conditions in the video. This will help viewers understand the role of carbon dioxide consumption and oxygen release during photosynthesis.
Investigation 1: Demonstrating Carbon Dioxide Absorption in Photosynthesis
Materials:
1. Potted plant (preferably one that has visible leaves)
2. Clear, airtight container (such as a glass jar or a plastic container with a lid)
3. Water
4. Sodium bicarbonate (baking soda)
5. Light source (e.g., sunlight or a lamp)
6. pH indicator solution (e.g., bromothymol blue)
Data to collect:
1. Initial and final water levels in the container
2. pH levels before and after the experiment
Procedure:
1. Fill the container halfway with water and add a few drops of the pH indicator solution. Mix it gently to distribute the indicator in the water.
2. Place the potted plant in the container, ensuring that the leaves are above the water level.
3. Seal the container, making it airtight. You can use the lid or cover the opening with cling film secured with a rubber band.
4. Expose the container to a light source for a few hours. This simulates sunlight, which is vital for photosynthesis.
5. Observe and record the initial water level and pH level.
6. After a few hours, observe and record any changes in the water level and pH level.
- A decrease in water level would indicate the plant has absorbed water during the experiment.
- If the pH level decreases, it suggests that carbon dioxide has been absorbed since it combines with water to form carbonic acid.
Conclusion:
If the water level decreases and the pH level drops, it demonstrates that the plant has absorbed carbon dioxide during photosynthesis.
Investigation 2: Demonstrating Oxygen Release in Photosynthesis
Materials:
1. Elodea or any aquatic plant
2. Test tube or clear glass container
3. Water
4. Sodium hydroxide (NaOH) pellets (to absorb carbon dioxide)
5. Light source (e.g., sunlight or a lamp)
6. Test tube stopper or rubber stopper with a small tube attached
Data to collect:
1. Initial and final water levels in the test tube
2. Dissolved oxygen level (if available)
Procedure:
1. Fill the test tube or glass container with water, leaving enough space for the plant to submerge.
2. Insert the plant (e.g., elodea) in the water, making sure it is fully submerged.
3. Add a small piece of sodium hydroxide pellet to absorb any carbon dioxide present in the container, helping to ensure that all oxygen produced comes from photosynthesis.
4. Attach the test tube stopper or rubber stopper with a small tube to the container. This setup allows the oxygen produced to collect in the top of the test tube.
5. Place the container under a light source for a few hours.
6. Observe and record the initial water level and, if possible, measure the initial dissolved oxygen level.
7. After a few hours, observe and record any changes in the water level and, if available, measure the final dissolved oxygen level.
Conclusion:
If the water level increases, and there is an increase in the dissolved oxygen level, it confirms that the plant has released oxygen during photosynthesis.
Remember, both investigations simulate the process of photosynthesis but may not provide precise measurements. Ensure you follow safety precautions and conduct the experiments in a controlled environment.