Mitosis/Meiosis experiment

After following the steps of the Scientific Method (see Chapter 1), you now have data supporting or failing to support a particular hypothesis. But how do you share this information with others? Publishing your results is an important component of the scientific process. By sharing data and results, other scientists can develop new hypotheses and build upon your body of work.

Scientists publish their work inside of peer-reviewed scientific journals. These journals may have slight changes in formatting, but in general, their articles follow a similar format.

• Abstract: A paragraph briefly describing the study’s hypothesis, methods, results, and relative importance. This gives the reader a general overview of the work so they can decide if they want to read the entire paper.
• Introduction: This explains any background needed for the reader to understand the study. It will explain what is already known in the field, and what still needs to be studied. It will introduce the study, as well as explain the hypothesis and/or predictions.
• Methods: This will detail the steps of the experiment, or how the scientists gathered data. It should be detailed enough so that someone could theoretically repeat the experiment.
• Results: This is a report of the data collected. It will include graphs if applicable, and any statistical tests.
• Discussion: This could be argued as the most important part of the paper; the “so what?” What do the results mean? Do the results support, or fail to support the hypothesis? Why, or why not? This is the place to explore alternate explanations for the data, and to suggest future areas of research.

Your Group Lab Report
You will explore an abbreviated version of this process by working on a lab report with your group members. This lab report will be over the Mitosis/Meiosis lab. Complete the following sections on this worksheet, or in a separate document. After completing the lab report as a group, don’t forget to submit your peer evaluation form.

For additional help, contact your instructor or view the sample lab report provided.

Experimental Hypothesis
Review the role of a hypothesis in the Scientific Method in Chapter 1. Your hypothesis should be an answer to your research question.

Example: I observe that birds at my bird feeder prefer to eat certain seeds over others. I wonder if birds are picking the seeds that contain more energy (calories) to feed on first. My research question is then: do birds pick foods based on calorie content? My hypothesis could be “Birds will preferentially consume high calorie seeds over low calorie seeds.”

Methods
Briefly summarize the methods you used in your experiment. It should be detailed enough for someone to repeat your experiment. DO NOT COPY AND PASTE FROM YOUR LAB MANUAL!!

Example: This experiment was carried out in a local park where wild songbirds have been observed. Shelled sunflower seeds (584 calories/ 100 g) and dried corn kernels (386 calories/100 g) were chosen as food sources due to their popularity in wild birdseed and their difference in caloric value. Two cups of sunflower seeds were placed on a ceramic plate under a tree. Two cups of dried corn kernels were placed on a separate ceramic plate located next to the plate containing sunflower seeds. The plates were left out for birds to feed on for six hours in the morning (5:00 – 11:00). An observer monitored the plates from a picnic table located approximately 200 meters away to ensure only songbirds fed from the plates. After six hours, the remaining mass of seed was weighed. This procedure was repeated for five days.

Results
Typically, the results section does not include raw data. However, for this report, include the data your group collected in your report. From that data, calculate the averages of your group data, and include your work in the final report. Report your data collected (averages, etc.) in sentence form.

Create a graph using your data. Your graph MUST include 1) Descriptive title, 2) axis labels, including units, and 3) legend or key, if applicable.

Example:

Volume seeds consumed
(cups)
Day Sunflower Corn
1 1.3 0.7
2 1.2 0.6
3 1.6 1.1
4 1.5 0.5

Work:
Average = sum of all data points/ number of data points
Sunflower average = (1.3 + 1.2 + 1.6 + 1.5)/ 4 = 5.6/4 = 1.4 Corn average = (0.7 + 0.6 + 1.1 + 0.5)/ 4 = 2.9/4 = 0.725

Of the five days of observation, data from only four days was analyzed. Data from the remaining day had to be discarded as squirrels consumed most of the seeds before any birds were sighted. Birds consumed more sunflower seeds (average =1.4 cups) than dried corn kernels (average = 0.7 cups) over the course of six hours (Figure 1).

Figure 1. Consumption of seeds by songbirds
Consumption of seeds by songbirds

Discussion
This is the “so what?” section. Explain whether or not the data supports your hypothesis. Discuss how your results fit into what is currently known on the subject. Finally, discuss any alternative explanations to your data and suggest future areas of research.

For this part of the paper, you will need to research some of the background on the experiment’s topic. You MUST use 2-3 sources in your discussion. These sources can include your textbook, credible websites, journal articles, books, etc. Wikipedia is NOT an acceptable source. These sources must be cited in the body of the paragraph and in a separate references section!

Example: When given a choice, birds preferentially fed from the calorie-rich sunflower seeds over corn kernels.
This supports our hypothesis that birds will choose and consume higher calorie foods over lower calorie foods. This is in line with optimal foraging theory, which posits that organisms should seek to optimize nutrient consumption against effort (Sinervo, 1997). A good example of this pattern was seen by Snellen et al. (2007), which observed that western gulls (Larus occidentalis) preferentially fed on high calorie sea urchins over other organisms in the rocky intertidal zone.

However, this study does not take into account handling time (Werner & Hall 1974). As sunflower seeds are much smaller than corn kernels, it may be that songbirds are basing some of their choice on ease of consumption. A follow-up study should examine the time for consuming a similar amount of sunflower seeds and corn kernels to account for this potential source of error.

In conclusion, while other aspects of feeding strategy may play a role in an organisms foraging pattern, calorie count is likely an important contributing factor.

Works Cited:
Sinervo, Barry. "Optimal foraging theory: constraints and cognitive processes." Behavioral ecology (1997): 105-130.

Snellen, C. L., P. J. Hodum, and E. Fernández-Juricic. "Assessing western gull predation on purple sea urchins in the rocky intertidal using optimal foraging theory." Canadian Journal of Zoology 85.2 (2007): 221-231.

Werner, Earl E., and Donald J. Hall. "Optimal foraging and the size selection of prey by the bluegill sunfish (Lepomis macrochirus)." Ecology 55.5 (1974): 1042-1052.