Photo Rate Lab Leaf Disk Assay. Period

Transcription

1 Photo Rate Lab Leaf Disk Assay Period

2 Claim: Plants that utilize the C3 method of photosynthesis will have the highest rate of photosynthesis when tested under direct light and during the day. Evidence: Reasoning: Respiration differs depending on the type of photosynthetic method utilized C3 Plants: -utilizes Rubisco enzyme, starts with 3-carbon structure -constantly goes through both light dependent and independent reactions -don t conserve water, are less efficient -data correlates with reasoning, took in sunlight and rose fastest C 4 plants: -utilizes PEP carboxylase enzyme, start with 4-carbon structure -prevents competitive inhibition by doing photosynthesis deep within the cell -should have photosynthesized, unknown causes or human error created inaccurate data CAM Plants: -close their stomata during the day and open it at night to store water, -inhibited photosynthesis, the leaf did not rise in time to record Photosynthe9c Method By Bay Johnson, Angelica Vohland, Amelia Shunk, Vicens Vila-Coury, and Jacob Zimmerman

3 Photosynthesis Leaf Disk Inves2ga2on: What factors affect photosynthesis rate? Claim: Photosynthe2c rate increases with increasing temperature. Josef, Ben, and Sean Evidence: Reasoning: Temperature 10 Celsius 25 Celsius 55 Celsius Mean (sec) N/A Standard Devia9on (sec) N/A Higher kine9c energy due to increased temperature increases the rate of collisions at a molecular level. Increased collisions with the adequate energy and orienta9on result in greater photosynthe9c rate. For every 10 Celsius increase, the theore9cal rate of photosynthesis should double. However, the doubling of reac9on rate will halt when the temperature becomes too high and denatures the enzymes by disturbing the hydrogen bonds maintaining their ter9ary structures. Both the light independent and light dependent reac9ons increase in reac9on rate due to the higher kine9c energy. The oxygen gas created during photosynthesis cause the leaf disks to rise. The faster the rate of reac9on, the more oxygen is made and will rise in less 9me. Therefore, as temperature increases, the photosynthe9c rate increases (un9l hits threshold for denaturing)

4 Photosynthesis Leaf Disc Investigation: How will disc size affect the rate of photosynthesis? Mean Time for 50% of Discs to Rise (sec) Claim: Photosynthetic rate increases with decreasing disc size. The Effect of Disc Size on Photosynthetic Rate: Size of Disc Reasoning: - The smaller the disc size the faster the photosynthetic rate, because there is a larger surface area to volume ratio. - The larger the surface area to volume ratio, the more CO2 that is absorbed. - The oxygen gas bubbles produced by the plants make the leaf disc rise. - The faster the oxygen is made, the faster the leaf discs will rise due to gasses in their cells. - The larger the leaf disc, the longer it takes for the sunlight to be absorbed by all of the chloroplasts within its cells. - Therefore, the smaller the disc, the greater the surface area to volume ratio, and the higher the photosynthetic rate.

5 Does the Surface Area of Spinach Leaves Disks Affect the Rate of Photosynthesis? Claim: The smaller the surface area the greater the rate of photosynthesis. Evidence: Surface Area of Disk vs. Photosynthesis rate Reasoning: The rate of photosynthesis was greater with a smaller surface area because there is less energy required for fewer chloroplasts. A spinach leaf with a larger surface area needs more energy for more chloroplasts, causing it to have a slower rate. KATIE PEOPLES, DIDI KELLEN, COURTNEY MORRIS, MARY LEONARD

6 The Effect of Color of Light on the Rate of Photosynthesis by: Claire Joyner, Lauren Foehr, Grace Westle, Pearl Zhong, and Alicia Vargelis Claim: If a red filter is used then the leaf disks will have the fastest rate of photosynthesis Evidence: Color of light v.s. Time (sec) Reasoning: The red light will have the fastest rate of photosynthesis because it is the most easily absorbed by chlorophyll A and B which absorb wavelengths of 680 nm and 700 nm Blue light will also have a fast rate of photosynthesis because it has the shortest wavelengths without damaging the cell (violet light damages the cell) As the wavelength shortens the amount of energy in each photon of light increases therefore increasing the rate of photosynthesis Therefore, blue will have a high rate of photosynthesis but red will have the highest rate because it is the most easily absorbed in photosystem 1 and 2

7 Claim: Photosynthe9c rate will be lowest when light color is green and highest when light color is red. Evidence - Light Color vs Photo Rate Clara, Andrea, Mya, Simon Reasoning - Spinach leaves are green since they reflect the green wavelength and so all the other color wavelengths are absorbed Therefore, the green light had the lowest photosynthe9c rate Chlorophyll a absorbs best in red wavelength and chlorophyll b absorbs best in blue- violet wavelength The more red and blue- violet photons emibed, the more photolysis is occurring therefore increasing photosynthesis rate The clear color can absorb wavelengths of all colors including red and blue- violet Oxygen gas bubbles produced in photosynthesis make the leaf discs rise. The faster the oxygen is made, the faster the leaf discs rise and vice versa.