AP Biology.

Determining the Tun State Temperature Threshold of Tardigrade

by Thomas Goydan (V), Saniya Kamat (V), Grant Lardizabal (VI)

The tardigrade is a semi-aquatic microorganism known for its ability to endure extreme conditions by undergoing cryptobiosis, withstanding temperatures ranging from near absolute zero to 151°C. The aim of our experiment is to determine the approximate temperature at which the tardigrade enters the tun state, a state of inactivity in which the tardigrade dries up and becomes dormant. To accomplish this, we used a pipette to collect tardigrades in small groups from a culture and then heated them in water using a hot plate. By observing the tardigrades at specific temperatures under a microscope, we found that the tardigrade enters the tun state at approximately 40°C. This research provides valuable insight into suspended animation, the temporary cessation of most vital functions without death, which operates in the same manner as the tun state. Suspended animation could potentially provide doctors with more time to perform surgeries, effectively saving many lives.

Determining the Ability of Lemna minor to Remove Nitrogen From Water Sources

by Camille Collins (VI), Maddie Humphreys (VI), Stephanie Ticas (VI)

Our project will provide information on Lemna minor’s ability to remove nitrogen from water sources, a potentially significant method to increase access to clean water. It is known that L. minor has nitrogen-removal abilities, so our project will provide further insight into its behavior in varying local environments. Specifically, we are measuring duckweed’s removal of nitrogen from three water sources, therefore determining which source duckweed is most effective in. We gathered water samples from each source and created groups without duckweed, as a control, and groups with duckweed to measure the change in nitrogen concentration. Our results have yet to provide an answer, but they will be important in further understanding the nitrogen removal abilities and efficacy of L. minor

Determining the Mutagenicity of Propylene Glycol and Formaldehyde

by Clayton Annis (VI), Melania Rosales (VI), Grace Stowe (VI)

Propylene glycol and formaldehyde are chemicals commonly found in vapes and e-cigarettes. Relatively new, these products have not endured extensive research on their potential long-term effect on humans. Our experiment is dedicated to discovering whether propylene glycol and formaldehyde are mutagenic. If so, they will pose a health risk for users of e-cigarettes and vapes. Formaldehyde is used in many types of glues, resins, and body embalming, and knowing whether or not these chemicals have mutagenic effects could lead to the usage of less harmful substitutes in the future. Initially, our experimental plan involved creating our own agar plates: one with adenine and one without adenine to simulate an environment where the implications of our mutagenic substances could be seen. Our results show that there is no statistically significant data, as our p-value is .74393 and therefore, there is no convincing evidence that formaldehyde and propylene glycol have a mutagenic effect on the growth of yeast with and without adenine. However, solely based on the amount of yeast growth lost, formaldehyde yielded less of a loss than propylene glycol by 71.776 cm2. Our findings suggest that formaldehyde and propylene glycol do not have mutagenic effects. This does not necessarily mean that they are completely safe for human consumption as the data suggests that when these chemicals were added to the yeast, there was a significant decrease in colony growth compared to the control. Further experiments must be done in order to fully understand the effects of these substances on both yeast and humans.