Blog #16: Physiology Experiment Conclusion

We've wrapped up our experiment, completed the graphs, and are currently finishing the last touches on our presentation for tomorrow's class! Here's a brief summary of our conclusion based on our graphs:

Our hypothesis was that the change in heart rate (from the initial period to the period after completing brief exercise) will be higher for taller students than shorter students. We thought this because the taller they are, the more their body has to work when running. Their heart rate spikes more than shorter students and so it takes them more time to get their heart back down to rest.

We created three graphs that summarized all of our data.
*Note that for graphs 1 and 3, the unit "Heart beats/minute" should be added to the y-axis label* 

 The graphs that we were really focused on analyzing were graphs 1 and 3 because they showed the change in heart rate and the height. Graph 2 illustrates the correlation between height and the time to rest, but we were primarily interested in height and change in heart rate. 

Graph 1 shows the heights and change in heart rates for the 30 girls that we tested (athletes and non-athletes). Athletes are in blue, and non-athletes in red. From the graph, the trend is that the taller the person, the higher the change in heart rate is. Thus, the slope of the line is greater than that of the non-athlete line of best fit. The person who had the second highest change in heart rate (105 b/m) was the second tallest person (180 cm) in the sample, and the person who was the tallest (187 cm) had the second highest change in heart rate (89b/m). The non-athletes were more similar in change in heart rate (especially for people who were between the heights of 160 and 170 cm) , and there isn't as much of a trend between height and heart rate like there is for athletes. 

Graph 3 shows the change in heart rate and the height. It appears that the shorter people in our data had higher changes in heart rates than the taller people, for most of our data points are between people who ranged from 150-170 cm tall. Many of those people between 160-170 cm had changes in heart rate above 60 b/m. This graph allows us to observe that the taller the person, the higher the change in heart rate, for there is a slight positive correlation. It's obviously scattered and not a perfect line, but it is a trend. Plus, there were sources of error.

Blog #15: Physiology Experiment Update

Our experiment is up and running! We've tested ourselves twice and started doing an actual trial today in class. Our big focus now is getting people to be our subjects in order to run our experiment. We have more athletes than non-athletes right now on our data list, so we need a few more athletes and several non-athletes. We're hoping to get a lot of trials done tomorrow as well as Friday. Each trial doesn't take much longer than three minutes we've discovered.

75 yards is indeed enough distance in order to get one's heart rate higher. We also have decided to our subjects count their pulse every fifteen seconds rather than thirty, which is what we initially thought would be best. With a smaller time interval, we believe we'll have more precise results. We start timing the subject for fifteen seconds while they count their pulse immediately after they complete the physical exercise. Then they rest for fifteen seconds, count pulse for fifteen seconds, etc... until their heart rate is back to its initial number. From practicing on each other and doing one trial today, we've noticed that it takes most people 1-2 minutes for their heart rates to return back to rest. The trend that is also apparent is that it takes athletes a shorter amount of time to return to rest than non-athletes, which theoretically makes sense if they exercise on a more intense and regular basis (they're used to the exercise & "cooling down").

It's interesting that we're keeping track of the time to rest. We could've even compared that for athletes and non-athletes for our experiment, but instead we are testing to see if there's a correlation between height and heart rate. My hypothesis is that the taller you are, the higher heart rate you will have (initially). Whether or not you are or aren't an athlete in season will dictate the final heart rate (after the exercise). I think this because people who have more height may have higher heart rates because it takes more energy and effort to keep their bodies moving than people who are not as tall. We haven't really discussed our hypothesis yet as a team, but we will ASAP before we really start doing a lot of trials. We'll test everyone in our bio class and hopefully have other volunteers from outside of it participate. This has been a fun experiment so far, and the results have been interesting!

Blog #14: Physiology Experiment Update

We have added several changes to our physiology experiment design today in class. We decided to include the athlete vs. non-athlete variable into our experiment for more accurate, precise results and because both groups could create a possible source of error if one were not included, which we could help eliminate by using both groups. The next question we had was: who do you consider to be an athlete? The juniors in our class all participate in some form of physical activity for a minimum of thee hours a week. With that in mind, there is a difference between lacrosse players who play two hours every day five days a week and people in a Yoga class who do yoga for one hour a day three times a week. So yes, we all exercise and keep our bodies moving, but some at higher intensities than others. We decided that when we do our experiment, we will ask our subjects how often they exercise per day. If it's two hours or more, we'll consider them athletes, and if it's less, they'll be in our non-athlete experimental group. This just made the most sense for our age group and lifestyle. It'll be interesting to have a bar graph that will compare (side-by-side) the heart rates for athletes and non-athletes who are similar in height. Will the 5'6" athlete have the same heart rate as the 5'6" non-athlete? That's what we want to determine.

This means that we will need more girls as subjects for our experiment. As of right now, we're hoping to have 12 girls of varying heights who are athletes and 12 girls of varying heights who are considered non-athletes in our minds.

In addition to adding that variable, we also changed the type of physical exercise for our experiment. Instead of running up and down stairs at a fast pace, we are going to measure out 75 yards for our subjects to run (25 yard increments, so each subject will pivot and go in the other direction twice). We hope that they'll run as fast as they can to get their heart rates up. We tested this ourselves today with about 65 yards, and our heart rates increased substantially from our resting heart rates. The 75 yards compared to the stair runs will be less dangerous and more convenient, for we can measure 25 yards out in various locations on campus.

Lastly, we decided that when we time our subjects' heart rate to rest, we are going to do it in fifteen second intervals because it will be easier to keep track of. With these tweaks in our experiment, we are about ready to randomly select our subjects and have them do some running and pulse checking! We also need to complete some further research in order for us to come up with a reasonable, educational hypothesis before we officially start the experiment. It's been a fun experiment design so far!

Blog #13: Intro to Physiology Experiment

For our final experiment in Research Biology (revolving around physiology), we have decided to perform an experiment based on heart rate and physical activity. Lucia, Mary, Melissa, and I want to test whether or not there is a correlation between heart rate and height. Therefore, the purpose of our experiment is to determine whether or not being taller means having a higher heart rate after doing physical activity or vice versa. Our current hypothesis is that the taller the person is, the higher her heart rate will be after taking part in some type of physical activity. We think this because taller people most likely have a higher heart rate because their bodies will be working harder to keep them moving and breathing compared to shorter people because they are bigger in size. We are going to test our experiment by choosing a minimum of twelve junior girls at Emma Willard School and having them partake in two stair runs in our science building. We are going to check their heart rate (pulse) before they move up and down the stairs and after as well as timing how long it takes their heart rate to go back to its normal rate (recovery time). In order to get the most accurate results as possible, we want to have our subjects run up and down the stairs as fast as possible to really get their hearts pumping. We considered adding the athlete vs. non-athlete variable into our experiment but decided to not have that be a part of our experiment in order to keep it more simple. However, that could be a possible source of error in our data because athletes might have a better recovery time, and their heart rates may take longer to rise if their endurance is better than a non-athlete. We will obviously need to test girls who are different in height while having a mix of short, medium, and tall girls. More details and info to come!

Our procedure will look something like this:

• measure height
• check pulse for 30 seconds
• have them do the stair run (up and down three flights of stairs two times)
• check pulse for 30 seconds
• time how long it takes to get to recover back to initial heart rate
• record all info

Blog 12: Genetics Experiment Update

The fast plants are planted and growing rapidly! We planted them last Thursday (2/5/15), so they have been growing for almost a full week. A very important part of our planting process was doing the calculations for the amount of excess phosphorus and fertilizer that we were going to use while planting the seeds. After carefully weighing fertilizer pellets, calculating how much phosphorus we should use that would be proportional to both the fertilizer and soil, and doing more calculations and checking over our work, we finally mixed the soil, fertilizer, and extra phosphorus in four separate bowls and planted the seeds for our four different groups. Recap: There are 16 cells/group, and we have 4 groups. The first group is neutral, so there was no added phosphorus but just the fertilizer and soil. The small group had more phosphorus, the medium group had twice as much as the small group, and the large had twice as much phosphorus as the medium group. Doubling the amount of phosphorus made the most sense to us, and we felt that it would help our experiment succeed. Here is a low down of the measurements in a more clear and concise form: 
Added phosphorus to our plants:
small- 0.032g/group (0.002g/cell)
medium- 0.064g/group (0.004g/cell)
large- 0.128g/group (0.008g/cell)
Soil:
16.08g/group (64.32g total)
Fertilizer: 
0.384g/group (0.024g/cell & 6.144g total) 
Here are pictures that we took today when the plants were six days old. The stems all seem purple (may be hard to see in pictures), and we haven't really identified a huge change in' purpleness' between the four different groups. We are going to keep watching them and look more closely at the color intensities as we start wrapping up the experiment. This makes me question if we didn't add the appropriate amount of phosphorus or if phosphorus was not the variable to manipulate in our experiment. However, we did our research and are going to keep watching our data to see if it supports our hypothesis or not. Stay tuned! 

Blog 11: Annotated Bibliography for Genetics Experiment

Source 1:
Rhoades, H. (2009, August 6). The Importance Of Phosphorus In Plant Growth. Retrieved January 29, 2015, from http://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm

This source is important because it demonstrates the importance of phosphorus and plant growth. Phosphorus helps produce healthy plants, and it is especially significant when growing plants in gardens to use fertilizer that has phosphorus in it because it makes them strong and beautiful. It also introduces the term 'phosphorus deficiency'.


Source 2:
Soils - Part 6: Phosphorus and Potassium in the Soil. (n.d.). Retrieved January 29, 2015, from http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447043&topicorder=2

This source provides additional information about phosphorus deficiency. It discusses coloring in plants (especially red/purple and dark green) in more depth than the previous source and emphasizes the importance of phosphorus in soil for growing plants. This element mainly promotes root growth and hastens maturity.

Blog 10: Genetics Experiment Update

We are all set up for our experiment, but we are waiting on the phosphorus to arrive before we can plant our fast plants. Therefore, we are doing research now and finishing up our planning and calculations. This is what our set up looks like:

We have four groups of plants: neutral, small, medium, and large. There are 16 cells per group, and we are planting three seeds per cell. We are also going to place 3 fertilizer pellets in each cell. Therefore, there will be 192 fertilizer pellets and seeds total in all four groups. As you can see, we have already added wisps in each cell (the blue rhombus-like materials). We have not yet determined the exact lighting or watering system yet, but we will have a better idea when we actually being the process of planting. We know that it will be a constant system. However, we have decided how much extra phosphorus we will be adding to the small, medium, and large groups. The neutral group will still have 3 fertilizer pellets in each cell, but we will not be adding any additional fertilizer. What we did was find the average amount of phosphorus in 3 pellets. We found the average weight of 3 fertilizer pellets is 0.071 g. Then we took that number and found the value that is 14% of that because the fertilizer is a 14-14-14% ration of nitrogen, phosphorus, and potassium. That number we determined was 0.001 g. Therefore, in each cell (with 3 fertilizer pellets and 3 seeds), there is 0.001 g of phosphorus. We decided that it makes the most sense and we will get good results if we double the amount of phosphorus for each group. That means that the small group will have 0.002 g of phosphorus added in each cell, medium group 0.004 g, and large group 0.008 g. I've never worked with fast plants before, so I'm excited and hoping to see some different lovely shades of purple!

Blog 9: Intro to Genetics Experiment

Olivia, Lucia, and I have decided to do our genetics experiment using fast plants. We chose this model organism because fast plants are easy to use while carrying out an experiment, and we designed a good experiment that we feel confident about. From preliminary research, we have decided to plant Wisconsin Fast Plants Purple Stem (Hairy seed, high anthocyanin expression) in our lab. We are unsure of exactly how many we are going to plant right now, but we do know that we want to have four different groups. Our variable that revolves around our experiment in Phosphorus. After doing research, we concluded that Phosphorus is the element that makes Wisconsin Fast Plants Purple Stem have purple stems. Therefore, our hypothesis is that the more Phosphorus in the soil that the fast plants are growing in, the more purple the stems will be. We are going to control the Phosphorus quantities by using a fertilizer that is 14-14-14 (NPK: 14% Nitrogen, 14% Phosphorus, 14% Potassium). We will put three fertilizer "seeds" in each plant and add more Phosphorus in different amounts. We are in the process of ordering raw Phosphorus and will measure it by weight before adding it in with the soil and 14-14-14 fertilizer. We are unsure of what form the raw Phosphorus is going to come in so that is why we are going to measure it by weight, whether it is a solid or liquid. The four groups I mentioned above will include a: Neutral group (only fertilizer- no added Phosphorus), minimal added Phosphorus, medium added Phosphorus, and large amount of added Phosphorus. As we go into more depth of experiment design, we may add or alter the groups of fast plants we are going to test. I'm hoping that we will be able to see a distinct difference between the plants that get more Phosphorus. More details and progress to come soon!

Blog 8: Evolutionary Tree

This is the modified evolutionary tree we created while studying the mammalian hibernation patterns of the Ursidae family (the bear family). Mammalian hibernation is defined as a type of hibernation that has a specialized, seasonal reduction in metabolism that is concurrent with scare food and cold weather. Therefore, bears that perform mammalian hibernation hibernate during the coldest periods of wintertime. If they did not, they would have a slim chance of surviving the brutal weather that winter brings. Our hypothesis was that bear hibernation is not ancestral. Therefore, it is not a trait found in the common ancestor.

Our data supports our hypothesis; bear mammalian hibernation is not ancestral. According to our data, only the Brown and American Black bear demonstrate mammalian hibernation; the Sun, Sloth, Andean bear, and Giant Panda do not mammalian hibernate to any extent; the Polar Bear and Asiatic Black Bear perform some characteristics of mammalian hibernation, but they do not fully mammalian hibernate. Clearly this behavior is not found in the common ancestor and therefore did not evolve over time. However, we discovered a reasonable answer as to why two bears in the Ursidae family fully mammalian hibernate, four do not at all, and two semi do. The bears that hibernate are bears that live in geographic regions where the winters are extremely cold. Thus, they hibernate for a few months in order to survive the winter months. They crawl into dens and remain in a tight ball until their hibernation period is over. The heart rate drops as well as the body temperature during this time. The bears that do not hibernate are bears that live in somewhat tropical regions where there is not a harsh winter. Therefore, there is no reason to hibernate if there is both food available and temperatures that don't reach below freezing all year round. For the two bears that semi-hibernate (the Polar and Asiatic black), it's slightly different. It's cold year round where Polar bears live, so the specie is already accustomed to surviving the cold temperatures. With that said, they do not perform mammalian hibernation like the Black and Brown bears do but rather remain in their dens for relatively long periods of time (several months). Asiatic black bears live in several different areas of southern Asia where there are two different climates with different temperatures. Therefore, only bears in the northern part of the region in their habitat mammalian hibernate whereas the bears in the southern part do not; some will sleep the whole winter, and some will sleep only during the harshest parts of it.  From our data, we concluded that bears use mammalian hibernation as a defense against the cold, harsh winter months. If bears live in areas where there aren't tough winters, then they don't hibernate. Therefore, the trait didn't start in the common ancestor (the Giant Panda according to our evolutionary tree) but emerged as the different bear species did.