Project Objective
To design and execute an experiment to test how the body maintains homeostasis, in one aspect, and represent the findings through a lab report and poster session. Our group decided to test the acidity and alkalinity of human saliva.
Key Concepts and Terms
Scientific Method: A method of procedure used to study the world through observation, measurement, experimentation, formulation, testing, with a significant sample size consistently, analyzing, communicating, and revising.
Homeostasis: The tendency to resist change, in order to maintain a stable and relatively constant environment, using a negative feedback loop to counteract the change, toward its starting state, or in some cases, a positive feedback loop to move the system away from the starting state.
Homeostasis: The tendency to resist change, in order to maintain a stable and relatively constant environment, using a negative feedback loop to counteract the change, toward its starting state, or in some cases, a positive feedback loop to move the system away from the starting state.
- Different Types of Homeostasis:
- Core Body Temperature
- Blood Glucose
- Plasma Ionized Calcium
- Blood Partial Pressure of Oxygen and Carbon Dioxide
- Blood Oxygen Content
- Arterial Blood Pressure
- Extracellular Sodium Concentration
- Extracellular Potassium Concentration
- Volume of Body Water
- Extracellular Fluid pH
- Cerebrospinal Fluid
- Breathing Rate
- Weight
- Mucus Levels
- Salivary Homeostasis: Saliva is supersaturated with various ions. Certain salivary proteins prevent precipitation, which would form salts. It buffers (releases a chemical that absorbs excess ions to maintain constant ion concentration) the acidity of the mouth within a certain range, typically pH 6.2–7.4. This prevents minerals in the dental hard tissues from dissolving.
Application of Concepts
The scientific method was used to create a lab out of investigation about pH levels in human saliva and homeostasis. With this, a procedure, materials list, and experimenting were created. In the lab we manipulated the mouth's salivary environment by having our subjects drink from a baking soda-lemonade solution, to decrease the pH by 1, acidifying it, and also take a baking soda solution to increase the pH by 1, alkalizing it, and checking-in at 45 second intervals, until the pH normalizes.
The Product
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Lab Report
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Poster
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Reflection
For this project I learned to manipulated a solution for a desired pH, and how to format in Google Docs, although this skill came in too late. I also learned how to run and create materials needed for a test, and become more comfortable with presenting. With this said, making an all-inclusive materials list, without going back to find more materials, and general bad organization, especially with materials and job delegation, were some issues. Even though the lab designing phase was trying, to say the least, as a group we made sure we could make the testing solutions, work reliably, and had a specific procedure, which took longer than we had planned, but expected. Surprisingly, making our test practical was challenging for us, as we had broken a beaker, and exhausted our pH strip supply, in the process. Although we had some set-backs, we were able to overcome them, for a project that I can be satisfied with. The group dynamic was very playful and friendly, sidetracking at some points, but in the end everyone worked effectively. Overall, designing a lab is very difficult process, especially the materials and the procedure. We could have improved this project by having more solid research and formatting skills. To better the project, I would have more rigid presentation time intervals, to make sure everyone has an equal opportunity in taking notes from the rest pf the groups, while also carrying the weight for presenting our findings.
- Nihal Nazeem.
- Nihal Nazeem.