Fern Life Cycle

Introduction: This essay will discuss the fern life cycle as taught in biology lab. The essay will cover the basic process which we used to grow a fern. I will discuss the methods and the results of the lab exercise. Finally, I will discuss the evidence of the methods and results that were obtained . Methods and Results: To begin our experiment we obtained a petri dish from our lab instructor which contained fern spores and the food they needed to survive. We then look at the spores through the micro scope. It was to soon to see anything but little green dots. We then put our petri dishes under a light until next week. When we came in next week we observed our fern spores through the dissecting microscope. We looked to see if we could find anything germinating. We quickly noticed something that appeared like an air bubble squirting out something green. This was our fern spore which was germinating. Next, we removed a few of the germinating spores from the petri dish and put them under a compound microscope scope. We found the spore wall and observed how the developing gametophyte had broken through the wall, as instructed by our lab manuals. One could also identify the chloroplasts with in the cell. We then put up our dishes for another week. The third week of our fern lab we identified the difference between male and female gametophytes. We did this by taking a culture from our petri dish and placing it under a dissecting microscope. Due to the male and female being both located on the same prothallus it was necessary to obtain the exact location of the antherium and the archegonium from the lab book or the instructor. Once this was done it was fairly easy to tell the difference between the male gametophyte or (antheridium) and female gametophyte (archegonium) on the prothallus. The antheridium was located around the perimeter of the prothallus, near the rhizoids. The antheridium was located near the growing notch on the under side of the prothallus. To me the growing notch seem to like red dots set up like bowling pins. We also observed sperm swimming around the archegonium. We then put our fern lab petri dishes back under the light until next week. By the forth week of our fern lab experiment our gametophytes had grown quite a bit. We briefly looked at them under a compound microscope, but there was no valuable information learned from this. The gametophytes would be large enough in the next couple of weeks to transplant them into three liter soda bottles to grow into full size fern plant. This would complete our fern life cycle experiment. Discussion: In this section I will talk a little about what I learned from the fern life cycle from first germination to final result, a full grown fern plant. I will begin by saying that I had to learn a lot of specific terms to be able to follow the experiment. It is imperative to understand the basics get a handle on the whole. Anyway, I will start from the beginning. I learned that their were several different stages in which a fern had to go through in order to grow into an adult plant. I will describe the fern life cycle as learned in biology lab and the lab manual. First the fern was given to us as a gametophyte. The gametophyte contains an antheridium, which is the male sex organ that produces the sperm, and the archegonim, the female sex organ were fertilization takes place. This allows the fern gametphyte to fertilize itself. Once this happens the gametophyte will give rise to a sporophyte. Then the sporophyte will produce more spores and the spores will produce more gametophytes, thus completing the cycle of life once again. I learned a lot by watching the experiments through a microscope. The hands on experience really help to understand what was going on in the gametophyte. When one could actually see the archegonium and the anteridium on the prothallus it seem to help make sense of the lab experiment. One could even see the sperm going to the aechegonium, which lead to fertilization. I can remember looking into the microscope and seeing the green ooze squeezing out of the cell wall. In conclusion, all of this combined lead me to believe the fern life cycle did indeed happen as the lab book and instructor had taught. The experience of studying the fern life cycle did spark my curiosity in the development of life from cells. It really amazed to see an adult fern grow from something I had to look at through a microscope.