1. By Kacie Capozzoli, Jenny Nguyen, and Chuck Thonsen
How do algae respond to light? Determining the Process of Phototaxis in Chlamydomonas reinhardtii
By Kacie Capozzoli, Jenny Nguyen, and Chuck Thonsen

2. Background/Basis for Experiment
Wild type Chlamydomon as reinhardtii move toward white light in the process of phototaxis, but the mutant strain does not.
The inability of the mutant to perform phototaxis may be due to the eyespot being too small or weak, and unable to detect certain wavelengths of light.

3. Specific Questions and Predictions
What caused the mutant strains of Chlamydomonas reinhardtii to be immotile and unable to perform phototaxis?
Would the eyespot of the mutant strain be able to detect blue light?
In presence of both white light and blue light, which type of light will the mutant strain go towards?
Biological Prediction: The mutant strain will move towards the blue light, even when competing with the source of white light.

4. Results TRIAL 1: Phototaxis CC-125 (wildtype) CC-2894 (mutant) control
CC-125 (wildtype)
CC-2894 (mutant)
control
blue light
(++)
white light
Physical appearance
control- no movement, blue and white light- clumps, but minimal movement towards the light (ring)
control - clumps spread out and no movement, blue and white light- moving to light
TRIAL 2: Phototaxis
CC-125 (wildtype)
CC-2894 (mutant)
control
blue light
(++)
white light +
Physical appearance
control- no movement, blue light- clumps, but minimal movement to light, white light- moving to light (very faint)
control- clumps spread out and no movement, blue light- moving towards light, white light- clumps, but little movement towards light (ring)
COMPETITION
TRIAL 2
white light
blue light
CC-125 (wildtype)
CC-2894 (mutant)
(++)
Physical appearance
WT strain- no movement, mutant strain- moving to light
COMPETITION
TRIAL 1
white light
blue light
CC-125 (wildtype)
(++)
CC-2894 (mutant)
Physical appearance
WT strain- minimal movement towards light, mutant strain- no movement towards light
WT strain- moving towards light, mutant strain- no movement