|Explore||- Spider plants (Chlorophytum comosum) are perennial herbs that are to grow to 60cm high. - Often found in the variegated variety (usually Vittatum or Variegatum), though purely green spider plants also exist. - Able to thrive in a variety of abiotic factors; tolerates temperature down to 35...|
|Research Question||What effect does humidity have on the growth of tuberous routes (spiderettes) of spider plants (Chlorophytum comosum)?|
|Predictions||There are three possible outcomes to our experiment: the plants' roots with the increased humidity will grow more than the plants with regular humidity; there will be no significant difference between the root growth of the increased humidity plants and regular humidity plants; the plants' roots...|
|Experimental Design||Our plan is to test the effect of the relative humidity of the baby spider plants. The variable that we are testing is the relative humidity. We are going to have two levels of the independent variable: no enhanced humidity and enhanced humidity. In order to achieve these levels. we set up 12...|
|Conclusion||What claim can we make from our experiment? What are possible explanations for our results? How do the data we collected and our reasoning with scientific ideas support our claim? What future experiments could be done to expand on the results of this experiment?|
Hi Win(sto)ning Team,
First I want to congratulate you on a job well done! I just started reading your Final Report and it is amazing. Everyone has put in a lot of time and attention to details from the experimental setup to measurements and results. Please pat yourself on the back!
Second there are a few things I wanted to point out. It makes me smile that you have stated that your prediction was wrong and that the plants with humidity may not grow as well as plants without humidity. You would be surprised how many people at every stage of a science career don't have the courage to say that their prediction was wrong. Third I wanted to applaud you for diligently mastering every part of the your project. You came up with a great idea to test and hopefully future classes will consider testing different treatments using spider plants! Fina;ly your graphs look amazing. Figure 8 and 10 in particular show exactly what you determined in your conclusion.
It was an honor working with you this term.
PS I finished reading the report and your observation of the "bag effect" is awesome! In my mind it clearly suggests that the bag could be helping growth like it was a miniature greenhouse! Awesome observation!
Now that our experiment has concluded and our research paper has been written (attached in files) we would like to thank you for all the help you have given us. Your questions, observations, and general feedback not only helped us improve and refine our experiment, but also helped us reach a deeper understanding of several topics involved in the experiment.
Thank you so much!
Josh, Kyle, Phylicia, Arsh, and Winston
I would like to personally thank you for the effort you put into helping us with our planting science experiment. Your guidance helped us improve the experiment and investigate topics that we would have never otherwise considered. You were extremely active and gave helpful feedback to all of our posts. It was greatly appreciated.
Our team hypothesized that increasing the relative humidity level would have a positive effect on the growth of the tuberous roots of spiderettes. However, our hypothesis was disproven because the presence of a sponge inside the plastic bag had no significant influence on on root growth. On average, the total root length for the spiderettes without increased humidity was 3.783 cm more than the total root length for the spiderettes with increased humidity. From this, our team concluded that increased humidity may have a negative effect on root growth. Additionally, we may have increased the humidity too much, which was harmful to the spiderettes.
We will also be uploading the paper for our experiment soon.
During the final collection phase of our data, we had to measure the roots of the spiderettes. We did this by cutting the spiderette off using one of our teacher's pruning snip. Afterwards, we laid it off against a standardized graph paper and measured the roots with a ruler.
While creating the graphs and charts for this information, we found that the plants with the sponge inside its bag generally grew less than their counterparts without the sponge. Despite this, the bag without the sponge contained plants that grew significantly more tuberous roots than that lacking a plastic bag.
This has led us to believe that there is a limit of humidity in which the spiderette tuberous roots grow at optimum.
Phylicia mentioned you did not see a difference in root growth between the two treatments. What are some ideas as to why this may be the case? Also what was the measured difference in humidity between the different groups of bags?
Thank you for uploading the photos. I am now interested if your results would change if you cut the plantlets from the mother plant. It is hard to tell but this may induce rooting. Do you know if there were any roots on the plantlets before starting the experiment?
Over the past two weeks we have collected data for the root growth (number or roots per plant in addition to the average root length for each plant). Today, our group began the completion of our final write up for our project. My job was to list all the materials, equipment, and facilities that we used during the the course of the experiment. I am also writing about our suggestions for further study if we were to continue upon our hypothesis.
The software we are using to collect data about the humidity of the ziploc bags is called Logger Pro. Here is a link to their website if you want to know more about it: https://www.vernier.com/products/software/lp/ .
It is a software that is connected to the humidity sensor, and it graphs the humidity levels, changing every second. We are using this setup to collect data for the humidity levels right now. I uploaded the photo of the setup so that you can visualize it.
Overall, we aren't seeing a significant difference in the number of roots so far. There was no change for some pairs, while there was a drastic change for other pairs. The average number of roots when we increased humidity was 5.2, and the average number of roots when we did not increase humidity was 5.6.
As we were collecting our data relating to the humidity of each of the bags, we noticed there were a few droplets of water on the inside of the ziploc bags that did not have sponges in them. Mr. Roche brought this up to us when he noticed it and informed us that it was probably because the plants were transpiring. We believe this is contributing to the rise of humidity levels in all the ziploc bags.
We are collecting the following pieces of data:
- The root lengths of each root of each spider plant
- The final humidity of each plastic bag (as well as the outside humidity)
- The number of roots each spider plant has
Recently, we have began collecting data in a manner in which to ensure standardization in procedure as to minimalize variation in data stemming from the collection phase. The relative humidity sensor is the same model as detailed before, and is able to collect information both precisely and accurately. It is connected to Vernier's "Logger Pro" software, which record the data.
The process is as follows:
1. The plastic bag is opened
2. Immediately afterwards, the relative humidity sensor baton is inserted parallel to the opposite edge of the plastic bag as to reduce gas exchange from occurring due to the opening of the plastic bag.
3. The sensor is engaged and held stationary for about 30 seconds
4. The sensor is able to record the data onto the software, and is extracted from the bag.
5. The bag is resealed.
6. Repeat steps 1-6 for all twenty-four spider plants.
During our data collection, we ran into a rather significant. The aforementioned problem concerns the integrity of our data collection, as operational error may have corrupted certain data points; the humidity sensor seemed to have malfunctioned towards the end of our activities, since it was giving faulty humidity sensor readings; therefore, we had to suspend procedures until we could resolve this issue. Over a duration of half an hour, we were able to redress this problem and return to collecting humidity readings.
Right now we are collecting data from our spider plants. One interesting observation we noted is the difference in growth between the plants in the bags and the plants outside of it. The plants inside the bags, regardless of whether or not they have the sponge, have much more, and much larger roots than the plants outside of the bags. We think that this may be due to the greenhouse effect you mentioned and because of the way moisture is trapped inside the plastic bags.
Today, we collected data on the number of roots. I will reupload the team planning document so you can see our data.
Our group was wondering about the viability of making the sandwich bags airtight. We are worried if this will interfere with the oxygen and carbon dioxide supply of the plant. Furthermore, this may hinder any opportunities to re-add water to the sponges.
Of course, we will heed your advice. We can try to do two trial runs with the air-tight seal.
We changed the amount of water added to each sponge per day to 1.5 mL, because we had trouble getting exactly 1 mL of water in the pipet. We believe that this will describe our experiment more accurately.