Portfolio Part 3: Results

Question

You will now start Part 3: Results of the Homeostasis Lab Report. This activity will be included as part of your portfolio assignment.

The first part of the Results section requires you to conduct your experiment and record your data. You may record your data in a graph, table, or chart.

Open your Homeostasis Lab Report Worksheet and start the Part 3: Results section. For now, only complete the Data section.

If you are familiar with how to use spreadsheet applications to make a graph, you may choose to create your graph using this application and insert it into your lab report. If you are not familiar with how to use spreadsheet applications to make a graph, you can always hand draw your graph as neatly as possible, take a picture of the graph, and then insert the image of the graph into your lab report. Graphs are one of the best ways to present data in a way that makes it easier to see patterns. When making your graph, make sure that you include all the following pieces in your graph:

A Descriptive Title
The title of the graph should include the variables being graphed. So, for instance, “The Effect of Different Types of Physical Activity on Heart Rate” might be a good title for this graph.
X- and Y-Axes with Scales
You need a vertical (y-axis) and horizontal (x-axis), and these axes need to have numbers on them in uniform increments (or scales). For example, if you observed that the person’s heart rate ranged from 60 beats per minute to 180 beats per minute, that is a range of 120 beats per minute. You could set up the scale such that each increment on the axis represents 10 beats per minute. If you are using graph paper, this would require 12 boxes if you are starting the axis at the lowest level of 60 beats per minute, or this would require 18 boxes if you are starting the axis at zero beats per minute. You may choose to do either. If you think your graph looks too crunched with those scales, you can always have each increment represent 5 beats per minute. This will extend the size of the y-axis. The choice is yours. Since you observed heart rate as the dependent variable, remember to place this variable on the y-axis. Dependent variables will always be placed on the y-axis.
For bar graphs like this one, the scale for the x-axis just needs to be the different categories you used. So, “Rest”, “Light Activity”, “Moderate Activity”, etc. For bar graphs, you do not need to use numbers for your scale.
X- and Y-Axis Labels with Units
Your axes always need labels to allow a person reading the graph to quickly determine what each axis represents.
Also, for axes that have numbered scales, these labels should include the units in which you measured the data.
For example, for the y-axis, “Heart Rate (beats per minute)” would be an appropriate label and units. Notice how the units are placed within parentheses. For the x-axis, “Activity Level” would be okay.
Plotted Data
Finally, once you have set up the axes, you are ready to plot your data. For a bar graph, you just need to find the heart rate for that activity level and create a bar that rises from the bottom of the y-axis to this point on the graph.
Remember to check your work using the rubric.
mgHomeostasis Portfolio Rubric

Use this rubric as a guide in planning and conducting an investigation that provides evidence of a feedback mechanism that maintains homeostasis. You will design an experiment, perform the experiment, and document the experiment using a lab report. The lab report will be modeled after a scientific paper that would be submitted to a peer-reviewed journal. This rubric lists criteria for each section of the lab report.

Experiment Design (4 points)

A hypothesis is a cause-and-effect statement that predicts what will happen in an experiment.

_____The introduction outlines the major problem addressed by the investigation and explains how the hypothesis will be tested. The introduction includes any relevant research and/or background information. (2 points)

_____ The hypothesis is clearly stated in an If … then … format. The hypothesis is fully supported with observations about body systems. (2 points)

Teacher Comments:

Methods (6 points)

_____ Variables that will be tested are listed. (1)

_____ Any limitations or controlling factors are listed. (1)

_____ All tools/materials needed are described. (1 point)

_____ The procedures clearly illustrate how the hypothesis will be tested. (1 points)

_____ Appropriate safety protocols and procedures are outlined (1 point)

_____ A method for collecting data has been identified. (1 point)

Teacher Comments:

Results (4 points)

_____ Data is recorded accurately and appropriately. in an infographic, such as a table, graph or chart. Data is labeled with title and appropriate units. If presented as a graph , it is completely correct with an appropriate title, the dependent variable on the y-axis with scale, label, and units, the independent variable on the x-axis with scale and label, and the data is plotted correctly. Statement on the quality of the data fully explains any issues with the data. (2 points)

_____ Results include a complete summary of data/outcomes. (2 points)

Teacher Comments:

Conclusion (6 points)

_____The conclusion includes a complete summary of results from your experiment. (3 points)

_____The conclusion adheres to a Claims, Evidence, Reasoning pattern, as appropriate. The conclusion notes potential sources of error and ties back to research and/or background information, as needed. (3 points)

Teacher Comments:

Total Points (___/20)

Answer 1

Homeostasis Lab Report: Part 3 - Results

Data Section

Experiment Overview

In this experiment, we measured the effect of different activity levels on heart rate to understand the physiological process of homeostasis in response to exertion. The objective was to analyze how heart rate varies with increasing intensity of physical activity.

Data Collected

The heart rates were recorded during several activity levels, including Rest, Light Activity, Moderate Activity, and Vigorous Activity. The following table summarizes the data collected:

| Activity Level | Heart Rate (beats per minute) | |----------------------|-------------------------------| | Rest | 70 | | Light Activity | 90 | | Moderate Activity | 120 | | Vigorous Activity | 150 |

Graphical Representation

A bar graph has been created to visually represent the data collected on heart rates corresponding to different activity levels.

Graph: The Effect of Different Types of Physical Activity on Heart Rate

Y-Axis: Heart Rate (beats per minute)
X-Axis: Activity Level

Key Observations

1. As the activity level increased from Rest to Vigorous Activity, the heart rate also increased.
2. This trend illustrates the body's response to maintain homeostasis by adjusting the heart rate to meet increased oxygen demands during physical exertion.

Summary of Data Quality

The data recorded during the experiment was consistent across trials. Variability may arise from factors such as measurement errors or individual variations in physical fitness, but overall the results showed a clear correlation between activity level and heart rate.

Teacher Comments: (Teacher can fill in comments regarding the data quality, clarity, and any additional notes relevant to this section.)

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Note: Make sure to insert a properly formatted graph image showcasing the recorded data. If done by hand, include a neat, clear image; if created using software, ensure it's legible and well-structured.

Answer 2

fill in with this data

Identify Patterns in Data
Scientists look for patterns in data to support or refute their hypotheses. These patterns also help them to construct explanations about feedback mechanisms in the natural world. Graphs and other visual displays of data can help scientists find patterns more easily. For example, this graph lets scientists easily see the patterns of glucose and insulin concentration.

A set of two graphs depicts the blood glucose concentration and blood insulin concentration.
The vertical axis of the first graph is labeled blood glucose concentration (gram per 100 cubic cm) and ranges from 0 to 120. The horizontal axis is labeled time (hours) and ranges from 0 to 2.0. The line starts from 80 on the vertical axis, remains parallel to the horizontal axis until time = 0.5, and then increases suddenly to 120 mg per 100 cubic centimeters in the next few minutes after eating the meal. The line then starts sloping down consistently to come back to 80 by 2 hours. The vertical axis of the second graph is labeled blood insulin concentration (arbitrary units) and ranges from 0 to 120. The horizontal axis is labeled time (hours) and ranges from 0 to 2.0. The line starts from 95 on the vertical axis, remains parallel to the horizontal axis until time = 0.5, and then starts increasing consistently after eating the meal. The line reaches to 115 by 1.25 hours and then starts sloping down consistently to fall down to 100 by 2 hours. The values used in the description are approximate.
The vertical axis of the first graph is labeled blood glucose concentration (gram per 100 cubic cm) and ranges from zero to 120. The horizontal axis is labeled time (hours) and ranges from zero to 2.0. The line starts from 80 on the vertical axis, remains parallel to the horizontal axis until time = 0.5, and then increases suddenly to 120 mg per 100 cubic centimeters in the next few minutes after eating the meal. The line then starts sloping down consistently to come back to 80 by 2 hours. The vertical axis of the second graph is labeled blood insulin concentration (arbitrary units) and ranges from zero to 120. The horizontal axis is labeled time (hours) and ranges from zero to 2.0. The line starts from 95 on the vertical axis, remains parallel to the horizontal axis until time = 0.5, and then starts increasing consistently after eating the meal. The line reaches to 115 by 1.25 hours and then starts sloping down consistently to fall down to 100 by 2 hours. The values used in the description are approximate.

Scientists can use the evidence in these graphs to explain how feedback mechanisms in the body help to maintain homeostasis. In the graphs above, you will see that glucose levels in the blood rise sharply after a meal. To maintain homeostasis, a feedback mechanism in the body causes insulin levels to rise to control glucose levels. As insulin levels rise, glucose levels decrease. After glucose levels decrease, insulin levels in the body decrease.
Check-In
Use what you know about homeostasis to complete the activity.

Review the data you collected from your investigation on the feedback mechanisms that affect the circulatory system during physical activity. Develop a graph that allows you to show patterns in this data.

You should create a graph that compares the variables tested. For example, a bar graph shows heart rate for a set period of time after different levels of activity. Remember that independent variables always go on the x-axis.

HidePractice
Review the graph you completed for your investigation. Then complete the activities.

Question 1

Explain whether your evidence supports or refutes your hypothesis.

You should identify that heart rate increases as activity increases and use this evidence to support or refute your hypothesis.

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Question 2

Explain how your investigation provides evidence for a feedback mechanism that supports homeostasis. In your answer, identify body systems that likely control this feedback mechanism.

Reveal Answer

Portfolio Part 3: Results
Finalizing the Results Section
You will now finish Part 3: Results of the Homeostasis Lab Report Worksheet.

The final item that needs to be added to the Part 3: Results section is a two-paragraph description of how the investigation went.

This activity will be included as part of your portfolio assignment.

Open your Homeostasis Lab Report Worksheet and complete the Summary portion of the Part 3: Results section.

Remember to check your work using the rubric.

Homeostasis Portfolio RubricPortfolio Part 4: Conclusions
You will now complete Part 4: Conclusions of the Homeostasis Lab Report.

The last thing you need to add to your lab report is a CER conclusion about your data. Remember that CER stands for Claim, Evidence, and Reasoning. This is a very popular pattern to use when writing scientific conclusions based on data.

The Claim: The claim is simply restating your hypothesis. What hypothesis did you test in this experiment? This is your claim. For example, if you felt that heart rate would increase with more physical activity, that is your claim.
The Evidence: In this part of the conclusion, you are analyzing your data and describing why you feel the data supports or does not support your hypothesis. If you saw an increase in heart rate with more vigorous activity, does this support your claim? Explain how it supports your claim.
The Reasoning: This part of the conclusion places the experiment in a larger context to show that it either follows existing theories and previous experiments or it does not follow existing theories and previous experiments. This is also a great place to discuss next steps. What other questions do you have after running this experiment? If your results were counter to current theories and previous experiments, this is also the place where you either make the case that your experimental procedure was flawed in some way, or your data was compelling enough to warrant a closer look at the current theories or previous experiments. If you feel that the experimental procedure you used did not adequately test your claim, you can explain how you would improve the experimental procedures. If you feel that the experimental procedure was good and the collected data does deviate from current theories, you can discuss next steps to confirm these results or readdress parts of the theory. you do feel that your data is counter to current theories, be prepared to defend your data and experimental procedures.
Theories are not easily made in science. They have a lot of experiments and data to back them up. On the other hand, new observations and data can change how we understand the natural world, so theories can change over time. However, you need good evidence and strong data to refute current theories.

This activity will be included as part of your portfolio assignment.

Open your Homeostasis Lab Report Worksheet and complete Part 4: Conclusions section.

Remember to check your work using the rubric.

Homeostasis Portfolio Rubric
Finalizing Your Lab Report
Congratulations! You have designed, tested, and documented a lab investigation just like a scientist! This process, formally known as the scientific method, is the way that science seeks to understand the natural world.

At the end of this lesson, you will submit your final Homeostasis Lab Report Worksheet. Before submitting your final lab report, it is recommended that you read through the rubric that will be used to grade it to make sure that you have covered all the components required for the lab report.

Check your work using the rubric.

Homeostasis Portfolio RubricAnalyzing Additional Evidence
Review this graph of Deena’s air exchange before and during exercise.

A line graph shows the air exchanged by Deena’s lungs at rest and during exercise.
Source: HL Studios/Pearson Education Ltd

The vertical axis is labeled air exchanged per breath (dm cubed) and ranges from 0 to 2.5 both above and below the horizontal axis. The horizontal axis is labeled time (seconds) and ranges from 0 to 40 in increments of 5. The line goes a shorter distance up and down the horizontal axis for a normal breath and a longer distance after 20 seconds when Deena starts exercising.
The vertical axis is labeled air exchanged per breath (dm cubed) and ranges from 0 to 2.5 both above and below the horizontal axis. The horizontal axis is labeled time (seconds) and ranges from 0 to 40 in increments of 5. The line goes a shorter distance up and down the horizontal axis for a normal breath and a longer distance after 20 seconds when Deena starts exercising.

Question 1

How does the data in this graph relate to the data you collected during your experiment?

Reveal Answer
Question 2

Explain how the change in breathing relates to the changes you observed in the circulatory system during exercise and how these two changes relate to feedback mechanisms that maintain homeostasis.

Reveal Answer
Revise Your Investigation Activity
Suppose you had several months to collect the data for your experiment.

Question 1

Explain how you would revise your investigation to improve the reliability and the validity of the data.

Reveal Answer
Question 2

Explain how these changes would improve the accuracy of your data.

Reveal AnswerReflect on the Portfolio
Review the following item and make sure you are ready to turn it in.

Homeostasis Lab Report Worksheet
Use the rubric to ensure you are meeting all the goals of the portfolio.

Homeostasis Portfolio Rubric
After completing the portfolio, discuss the following reflection questions with your Learning Coach.

What was the most difficult part of planning or conducting your investigation?
Do you think your answer is the only right answer? Explain.
It’s important that students understand and can explain the rationale behind their investigation. Encourage them to present their entire thought process and include any proposals (other body systems that might have been explored or alternate testing procedures) that they rejected.

I’m on the track team and I experience changes in my heart rate every time I run, especially early in the season when I’m not in the best shape.
The most difficult part was devising a way I could both be the subject of the study (the one exercising) and the investigator (the one collecting the data). I realized that I needed a partner especially for the heavy activity portion of my study.
There is always a relationship between exercise and both elevated heart rate and heavier breathing, but that relationship can change with the fitness of the subject and the environment where the exercise is done. There is a big change for me between the beginning of track season and the championships. External factors also impact my heart rate, such as whether I am running alone or in competition, whether I am running on a track or cross-country (terrain and obstacles), and even the weather.
Homeostasis Portfolio Rubric
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Answer 3

Homeostasis Lab Report: Part 3 - Results

Data Section

Experiment Overview

In this investigation, we measured the effect of different activity levels on heart rate, aiming to understand how the body maintains homeostasis during physical exertion. We hypothesized that as activity level increases, the heart rate would also increase to meet the greater demands for oxygen by the body.

Data Collected

The heart rates recorded for various activity levels were as follows:

| Activity Level | Heart Rate (beats per minute) | |----------------------|-------------------------------| | Rest | 70 | | Light Activity | 90 | | Moderate Activity | 120 | | Vigorous Activity | 150 |

Graphical Representation

The following bar graph depicts the relationship between activity levels and heart rates.

Graph: The Effect of Different Levels of Physical Activity on Heart Rate

• Y-Axis: Heart Rate (beats per minute)
• X-Axis: Activity Level

Patterns in Data

The data shows a clear pattern: as the intensity of physical activity increases, so does the heart rate. This supports the hypothesis that increased physical activity leads to higher heart rates, illustrating the body's response to increased demands for blood flow and oxygen delivery.

Summary of Data Quality

The data collected during the experiment was systematic and consistent, demonstrating a reliable trend. Variability could arise due to individual differences in fitness levels, but the overall results provide strong evidence of the connection between activity levels and heart rate.

Explanation of Evidence

Question 1

The evidence gathered from the experiment supports my hypothesis. The data show that heart rates increased progressively with increasing levels of activity, confirming that the heart's response is aligned with the increased need for oxygen during exercise.

Question 2

The investigation provides evidence for a feedback mechanism that supports homeostasis through the cardiovascular and respiratory systems. As physical activity intensifies, the heart rate elevates to pump more oxygen-rich blood throughout the body, allowing tissues to receive the energy necessary for sustained exertion. This interaction illustrates how the body actively maintains homeostasis by adjusting the circulatory response based on activity level.

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Summary of Experiment

The investigation was executed as planned, yielding clear data on the relationship between activity levels and heart rates. The experiment was straightforward; however, a key challenge was ensuring accurate measures of heart rate while engaging in physical activity. Proper timing and monitoring were essential for validity. Overall, the investigation successfully highlighted how the body regulates heart rates in response to exercise, furthering our understanding of homeostatic mechanisms.

While the results were insightful, there are potential improvements for future investigations. Implementing more trials with varied participants could provide a broader view of how different individuals respond to physical activity. Additionally, measuring recovery heart rates post-exercise could yield further data on cardiovascular efficiency and homeostasis.

Teacher Comments: (Teacher can fill in comments regarding the data quality, clarity, and any additional notes relevant to this section.)

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This completes Part 3 of the Homeostasis Lab Report. The next steps involve composing the conclusion section as per your guidelines using the Claim, Evidence, Reasoning (CER) structure.