Introduction:
Planarians are free-living aquatic flatworms that posses remarkable regeneration abilities in addition to its distinct negative phototaxis behavior. A wealth of research studies has thoroughly examined its photophobic behavior under different wave frequencies and light conditions. Planarian are highly sensitive to white light and wavelengths of high frequencies, blue-green range ( Paskin TR, 2014). Two basic pigment-cup eyes situated in the head region govern its photophobic behavior. These basic eyes allow planarian to sense light without forming any image, which eliminates other possible variables that might confound its photophobic behavior. Previous studies have demonstrated the dependency of photophobic behavior on both …show more content…
My study sheds light on photophobic behavior of Planarian with only one excised eye. This study gives us insight into the underlying mechanism of worms’ reaction to light. Many insects such as ants and bees utilize chemical Tropotaxis to orient themselves toward odor signals. Tropotaxis is defined as the ability of an organism to take simultaneous information from paired sensory receptors then compare the information before reacting to the signal. My hypothesis is that Planarian posses a similar Tropotaxis ability in its reaction to light, where it compares light signals hitting its left and right eyes before demonstrating a photophobic behavior. This hypothesis is tested by excising only one-eye and examining the behavioral pattern of Planarians under light conditions. We would expect Planarian to move in circles if using Tropotaxis as a mechanism for reacting to light. In addition, my study will explore Planarians’ behavioral pattern when right-eye is excised as compared to left-eye only. My hypothesis is that both patterns (left eye excised vs. right eye excised) will be a mirror image of one another. The other possibility would be that worms do not use photo Tropotaxis, therefore they will process rays of light …show more content…
Three walls are sealed with white tape in order to provide background contrast against which the worms can be viewed. The fourth wall is untapped, which is the side where rays of the light source enter. In addition, white silicon is applied to all four corners of the container to avoid having worms hiding under tape folds. A commercial white LED panel is used in the experiment. Light intensity is measured using a photometer at four different points across the plastic well.(P1: 50.3 µ W, P2: 40.3 µ W, P3: 30.3 µ W, P4: 22.3 µ W). The relative distances between points of measurements are: (lightsource-point1 = 10.5 cm, p1-p2= 3.7 cm, p2-p3= 3.5 cm, p3-p4 = 3.4
Planarians are free-living aquatic flatworms that posses remarkable regeneration abilities in addition to its distinct negative phototaxis behavior. A wealth of research studies has thoroughly examined its photophobic behavior under different wave frequencies and light conditions. Planarian are highly sensitive to white light and wavelengths of high frequencies, blue-green range ( Paskin TR, 2014). Two basic pigment-cup eyes situated in the head region govern its photophobic behavior. These basic eyes allow planarian to sense light without forming any image, which eliminates other possible variables that might confound its photophobic behavior. Previous studies have demonstrated the dependency of photophobic behavior on both …show more content…
My study sheds light on photophobic behavior of Planarian with only one excised eye. This study gives us insight into the underlying mechanism of worms’ reaction to light. Many insects such as ants and bees utilize chemical Tropotaxis to orient themselves toward odor signals. Tropotaxis is defined as the ability of an organism to take simultaneous information from paired sensory receptors then compare the information before reacting to the signal. My hypothesis is that Planarian posses a similar Tropotaxis ability in its reaction to light, where it compares light signals hitting its left and right eyes before demonstrating a photophobic behavior. This hypothesis is tested by excising only one-eye and examining the behavioral pattern of Planarians under light conditions. We would expect Planarian to move in circles if using Tropotaxis as a mechanism for reacting to light. In addition, my study will explore Planarians’ behavioral pattern when right-eye is excised as compared to left-eye only. My hypothesis is that both patterns (left eye excised vs. right eye excised) will be a mirror image of one another. The other possibility would be that worms do not use photo Tropotaxis, therefore they will process rays of light …show more content…
Three walls are sealed with white tape in order to provide background contrast against which the worms can be viewed. The fourth wall is untapped, which is the side where rays of the light source enter. In addition, white silicon is applied to all four corners of the container to avoid having worms hiding under tape folds. A commercial white LED panel is used in the experiment. Light intensity is measured using a photometer at four different points across the plastic well.(P1: 50.3 µ W, P2: 40.3 µ W, P3: 30.3 µ W, P4: 22.3 µ W). The relative distances between points of measurements are: (lightsource-point1 = 10.5 cm, p1-p2= 3.7 cm, p2-p3= 3.5 cm, p3-p4 = 3.4