The Four Billy Goats By: Abby Fearneyhough, Vidalia Freeman, Caitlin Garcia, Solomon Carpenter

Research Question How does adding carbon dioxide affect the male to hermaphrodite ratio of c-ferns?

Prediction We predict that if we add carbon dioxide, the hermaphrodite numbers would increase faster than the male numbers. This is because the carbon dioxide will help it have increased levels of photosynthesis. Photosynthesis will produce the energy for cell functions, including mitosis, which allows the cells to grow faster, and mature faster as well. Once there is fertilization, all the males die and dissolve and we predict the entire process would speed up so there would be increased hermaphrodite numbers.

Variables Independent Variable: Carbon Dioxide Dependent Variable: C-Ferns

Experimental Design To make sure our results are valid, we will be doing two trials. We will put our spores in sealed petri dishes with augur and add two drops of water every Monday, Wednesday, and Friday. We will add CO2 to two of our dishes every Monday, and we will have two controls that will have normal air. We will add CO2 by dissolving alka seltzer tablets in a beaker, and then using a tube to pipe it into the petri dish. To make sure that none of the CO2 escapes when we are adding it, we will cover our dishes with parafilm and use a hole punch to allow the pipe to transfer the CO2. The reason we are adding CO2 is because we know that plants need CO2 to survive and do photosynthesis. Photosynthesis produces the energy for cell functions like mitosis, which is the way plants grow, so we think that increasing photosynthesis will increase the rate of mitosis.We want to see how this will affect the male to hermaphrodite ratio. We will count all of the hermaphrodites and males and see what the ratio of them is. Finally, we will keep all of our petri dishes in a light box at a constant temperature of 80 degrees.

Data Week 1Week 2 MalesHermaphroditeMalesHermaphrodite Test Control Test Control

Graph

Conclusion We wanted to know how adding carbon dioxide to our petri dishes would affect the male to hermaphrodite ratio of the c-ferns. We predicted that the the ferns in the petri dishes that we added carbon dioxide into(experimental group) would grow faster and mature faster, resulting in more hermaphrodites than the dishes we didn't add carbon dioxide into (control group). We were wrong. We learned that when you add too much carbon dioxide into a certain atmosphere, it lowers the transpiration during photosynthesis. It slows down the growth because less nutritive solution is drawn through the plant. Our experimental group matured and grew much slower than our control group.