1. How Bleach Affects Spore Development
By Chelsea and Raja
Mentor: Allison Kidder
Research Question: Does bleach inhibit spore development?
Hypothesis: If we add bleach to our fern spores, then the fern spores will not grow at all.
We are testing to see if, after adding bleach, will affect spore development. By development, we mean the normal growth and functions of a Ceratopteris richardii, or C-Fern, spore.
We wanted to test this experiment because we wanted to see the affect of bleach on the spores.
Fern Gametophyte Development:
During week one of the fern’s life, we learned that the fern’s life begins when the sporangia releases tiny spores by flinging them. Most spores are homosporous, meaning that they produce only one type of spore. Over the span of a week or two, the spores will develop into a heart-shaped gametophyte (something that produces sperm or eggs). The gametophyte, a Haploid, will survive by the process of photosynthesis. Within a couple of days, the gametophyte (which is born with both male and female sex organs) will decide on gender through the process of sexual differntiation.
The sperm will fertilize the egg. The sperm comes from the Antheridia, and the egg comes from the Archegonia. The now-fertilized egg will develop into a sporophyte (something that prodcuces spores) which also happens to be a Diploid. It will grow from the Archegonia of the parent gametophyte. The now mature sporophyte will begin the process again.
Conclusion:
In our experiment, we had six dishes. Two had no bleach, just
The agar and the spores. Another two had ½ mil. Of bleach, and
The last two had 1 mil. Of bleach. In the dishes with no bleach,
The spores grew exceptionally well. In the dishes with bleach,
However, the spores did not grow at all, and the bleach
Completely liquefied the agar.
Our hypothesis was indeed supported. The agar was supposed to
Solidify and become a stronghold for the spores so they could
Grow. This was not the case for the bleached dishes. So, our
Hypothesis was supported.
If we were to retry this experiment, we would probably use less
Bleach, or a different concentrate all together, to get new
Results to contrast on the results we got in the lab with this
Bleach experiment.
Procedures:
Put on goggles and gloves. Sanitize your area with the isoproponol alcohol, and your gloved hands. Get your (6) Petri dishes, and mark each with what will be inside. We wrote the amount of bleach on each dish. Pour the melted agar into the Petri dishes. Get the Pipet and withdraw the desired amount of bleach. Pour into the Petri dishes (1/2 mil., 1 mil.). Close Petri dishes. Sow in the given amount of spores, and use the bent paperclip to do so. Get a paper towel, and run it under the tap water until damp. Fold into quarters and put it inside the plastic bag. Flip the Petri dishes upside down as you put them in the bag. Stacking is okay. Record any information or anything note-worthy every day for the next three weeks.
Control
½ mil. Bleach
1 mil. Bleach
Germination
Day 2
None
Differentiation
Day 9
Archegonia
Day 16
Sporophyte
Day 21
Materials:
Agar
(Plastic) Gloves / Goggles
70% Isoproponal Alcohol
Stirring Stick
(6) Petri Dishes
(1/2 mil., 1 mil.) Bleach (6%)
(1) Pipet