Photosynthesis lab elodea and bromothymol blue answers. elodea_lab_intro (1).docx 2022-10-27
Photosynthesis lab elodea and bromothymol blue answers Rating:
Photosynthesis is the process by which plants, algae, and some bacteria convert sunlight into energy. This process involves the conversion of carbon dioxide and water into glucose, a sugar, and oxygen. During photosynthesis, chlorophyll, a pigment found in the chloroplasts of plant cells, absorbs light energy and converts it into chemical energy.
One way to study photosynthesis is through the use of the aquatic plant Elodea and the pH indicator Bromothymol Blue (BTB). BTB is a weak acid that changes color in response to changes in the pH of a solution. When the pH is below 7, BTB is yellow. When the pH is above 7, BTB is blue.
In a photosynthesis lab, Elodea plants are placed in test tubes or other containers filled with BTB solution. The plants are then exposed to various conditions, such as different levels of light intensity or the presence of carbon dioxide, to observe the effect on photosynthesis.
For example, in one experiment, the Elodea plants may be placed in a dark room to simulate low light conditions. The BTB solution in the test tubes will initially be yellow due to the presence of carbon dioxide produced by the plants during respiration. However, as the plants undergo photosynthesis, they will consume the carbon dioxide and produce oxygen, causing the pH of the BTB solution to increase. This will result in a change in color from yellow to blue, indicating that photosynthesis is occurring.
In another experiment, the Elodea plants may be placed in a room with high levels of light intensity. Under these conditions, the plants will undergo photosynthesis at a faster rate, leading to a more rapid consumption of carbon dioxide and production of oxygen. This will result in a more pronounced change in the color of the BTB solution from yellow to blue.
By performing these experiments and observing the changes in the color of the BTB solution, students can learn about the factors that affect photosynthesis and the role of chlorophyll in this process. In addition, they can develop an understanding of the importance of photosynthesis in the lives of plants and the role it plays in the global carbon cycle.
They produce carbon dioxide during cellular respiration. Chlorophyll absorbs the energy of sunlight, and that energy is converted to chemical energy ATP and reducing power NADPH. Be sure that the film is heat resistant to avoid fire hazard. The pH drops due to the presence of hydrogen ions. Record the final color of the bromothymol blue solution for each color of light, as well as both controls. This is not completely true, as the biochemical pathways and energy forms differ, however many of the enzymatic steps used in both processes are the same. As light intensity increases distance between lamp and plant decreases the volume of oxygen or the rate of bubble production increases.
Place the remaining plants each under a colored lamp. . This will be assessed indirectly by measuring the amount of CO 2 given off or taken up by the plant. By accessing the Science Fair Project Ideas, you waive and renounce any claims against Education. This indicates that the rate of photosynthesis increases with light intensity.
Create a bar graph to illustrate your results. Carbon dioxide bubbled into water forms carbonic acid. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For one of the control plants, cover the test tube or glass completely with aluminum foil to block out any light. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Thus, plants, including elodea, like to "do it with the lights on". Be sure to completely seal the vessel to keep gas from entering or leaving.
Carbon dioxide combines with water to form carbonic acid H 2 CO 3 which dissociates into hydrogen ions H + and bicarbonate ions HCO 3 -. Plants use carbon dioxide and produce oxygen gas during photosynthesis. Visible light is made up of different colors of different wavelengths and energy. Thus, the more photosynthetic activity, the less acidic and more blue the bromothymol blue solution becomes as the plant uses carbon dioxide during photosynthesis. In this experiment, the student will place aquatic plants under different colors of light in a solution of bromothymol blue. Secure the film with tape. In the dark, only cellular respiration occurs.
CO 2 + H 2 O H 2 CO 3 H + + HCO 3 - During photosynthesis, plants would take up CO 2 from the water; we would therefore expect to see an increase in the pH of the water. These reactions absolutely require light, and are thus described as the "light-dependent reactions". Just be sure to use distilled water and dilute the entire supply only slightly. Record the initial color of the bromothymol blue solution. Set up the lamps at least several feet apart and away from windows. Although these reactions are called the "light-independent reactions", plants do not perform these reactions in the dark; they perform them in the light, as long as sufficient ATP and NADPH and CO 2 are available.
This must occur in order for a plant to accumulate biomass, and be productive. If you do not have enough solution, you may dilute it with a little water. Write a hypothesis to explain which color light will be best for photosynthesis and why. Compare your results to your hypothesis. In the process, H 2 O is split and O 2 is released as a by-product. Plants perform photosynthesis to create sugars and other organic compounds that they need to survive. Make sure that each piece looks healthy and has plenty of green leaves.
Allow the plants to remain under the lamps until the uncovered control has turned dark blue about 24-48 hours. In today's lab, we will study photosynthesis in elodea in the light, and will also study background respiration by observing elodea in the dark. The equation for this process, photosynthesis , is depicted below. Cover each test tube or glass with plastic wrap. C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + Chemical Energy ATP Notice that these two equations appear to be opposites. Note: the amount of CO 2 uptake in plants that are photosynthesizing far exceeds the amount of CO 2 released through respiration.
When plants are exposed to light, photosynthesis and cellular respiration both occur. Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. The plants should all be 12 inches 30 cm away from their lamp. The less photosynthetic activity, the more acidic and yellow the bromothymol blue solution becomes as the plant produces carbon dioxide during cellular respiration. In addition, your access to Education. Carbon dioxide from the atmosphere is then systematically reduced to carbohydrate using the ATP and NADPH generated in the light-dependent reactions.
For further information, consult your state's handbook of Science Safety. However, at sufficiently high levels of light intensity, the rate of oxygen evolution remains constant. Bromothymol blue is an acid-base indicator that turns yellow in acidic solutions and blue in alkaline solutions. Write the name of the colored film to be tested on each cup you can also use masking tape to label cups. Leave one lamp without a colored film as a control. Place a piece of elodea in each test tube or glass. Chlorophyll is a pigment in the chloroplast of the plant cell that absorbs energy from light and uses it to create compounds needed in photosynthesis.
Certain wavelengths of light are used by plants more than others. Photosynthesis and Cellular Respiration in Elodea Elodea is an aquatic plant that uses the energy from sunlight to synthesize carbohydrate from carbon dioxide. On the other hand, one might expect respiring plants to release small levels of CO 2 into the water, causing the pH to decline slightly. . . . .