co 2 diffusion through gelatin experiment presented by jennifer welborn
TRANSCRIPT
COCO22 Diffusion Through Diffusion Through
GelatinGelatin ExperimentExperiment
Presented by Presented by
Jennifer WelbornJennifer Welborn
Learning Goals..Through this PowerPoint, STEMDIGITAL
participants will:
See how the concept of diffusion is related to a variety of curricular standards
Understand how ADI software can be used to show the process and rate of diffusion both qualitatively and quantitatively
OVERVIEW
Multidiscipline Standards Alignment
Concept Development
Factors Affecting Rate of Diffusion
Diffusion and Global Environmental Change
Research Questions
Experiment--Diffusion of CO2 Through Gelatin: Model of Diffusion in Cells
Using the Digital Camera as a Data Collection Tool
Analyzing Data Using ADI Software
Standards Alignment
•Physical Science/Chemistry: particle motion theory; pH; temperature; mixtures and solutions; color change as an indicator of a change in physical properties/chemical composition; acid/base indicators and protonation
•Biology: passive transport; cellular structure, etc.
•Ecology/Environmental Science: environmental effects on living cells/systems
•Math: rates; relationships; data collection, organization, analysis, interpretation, ratios and proportions
DiffusionDiffusion– movement of a substance from a region of higher concentration to a region of lower concentration.
Diffusion continues until equilibrium--- the concentration of a substance is equal throughout a space
Diffusion and Cells
• Dissolved particles that are small or non-polar can diffuse through the cell membranes.
• The process of diffusion is one of the ways in which substances like oxygen, carbon dioxide and water move into and out of cells.
Carbon dioxide from the environment diffuses into plant cells
Factors That Affect Rate of Diffusion • Temperature• Concentration of material diffusing• Density of substance material is diffusing into• Particle Size
Research Question
Can a digital camera be used to observe and quantify a change in the color of gelatin with BTB in it as carbon dioxide diffuses through it over time?
Conducting the Experiment/Gathering and Analyzing Data
1. Set up the experiment according to the directions on the lab directions handout.
2. Photograph the control and a sample of each cube exposed to CO2 over time (1 hour, 6 hours).
3. Use the ADI line tool, R, G, B values and graph colors option (SPACIAL ANALYSIS ) to analyze data both qualitatively and quantitatively.
ADI QUALITATIVE ANALYSIS
Open a picture, then trim the photo to increase processing time
Click on Full Image..Recommended
Click on Trim and Use Image
Choose None
Select line tool option
Draw a line using a color of choice
Note beginning and ending coordinates
Note R,G, B values
Click these to fine tune
Placement of starting and
ending points
Zoom in to help you
Place the beginning and ending points
You can see all the colors or turn off some of them to focus on just one
All colors off except green
The Value of The Control
The color graph for the control offers a baseline of R, G, B values to the student.
The next set of slides shows a sample of gelatin exposed to CO2 and its corresponding graph after 30 minutes. ADI lets you keep the settings if you are photographing the same thing over time.
This is a qualitative graph of diffusionAt 30 minutes, the point at which the CO2
appears to have diffused is 10/100.
ADI for Quantitative Analysis of DIffusion
•ADI can be used to quantify diffusion as well.
•The petri dish in the photo has a known diameter.
•To quantify diffusion, follow the same steps for opening the photo but choose scale present in image.
Draw a diagonalacross the petri dish
Record actuallength
Draw line across gelatin
Length of gelatin line
Zoom in to help with accuracy
Draw a line to whereIt looks like the diffusion
ends
Length of diffusion line
Qualitative ~ 10/100 = .10
Quantitative: .312/3.39 = .09
Future Inquiry Possibilities
Using the Digital Camera as a data collection tool, observe how changing: temperature; density of gelatin; or concentration of the solute (CO2)--to mimic increasing CO2 levels--affects the rate of diffusion.