Modeling Exponential Population Growth B O N N I E  M C CO R M I C K http://www.nabt.org/websites/institution/File/pdfs/american_biology_teacher/2009/May%20/071-05-0291.pdf

Student Protocol

1. In your journal, create a Title  (reflecting independent and dependent variables). Use a ruler for all data tables and graphs. Label all column, units, axis, tables and graphs appropriately.

2. Cut open the pepper and count the number of seeds inside. Record the total in Data Table 2 and on the board so that a class total can be obtained. Assume that the number of bell peppers in the class represents the number of peppers produced by one bell pepper plant in a growing season.  Here is an example of a data table, make a blank one for your journal.

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3. Record the total number of seeds counted for the class.

4. To complete the Data Table, assume that:

(a) Only one bell pepper plant existed the first year and that it produced the number of seeds represented by the class total.

(b) Each seed always grows into a new bell pepper plant the next year.

(c) Each new plant always produces the class total number of seeds.

(d) All pepper plants die at the end of the year.

5. Find the number of bell pepper plants that grow in the second year and record this number in Data Table 2. (Check with other groups and the teacher to make sure that this step is performed correctly before continuing.)

6. Calculate the number of bell pepper plants that will grow in the second, third, and fourth years. Describe the method you used to calculate the number of plants for each generation. Write the method as a mathematical equation.

7. Graph your results using the graphing calculator. Sketch your graph in your journal.

8. Answer the questions in Table 3 in your journal. Use Table 4 to help you answer the last 3 questions (look below Table 3). For more information on how to do the graphs 

Logistic Growth Model

Exponential Growth Model

HW: Make a graph on the computer which includes the equation for the line. Print the graph and paste into your journal. Explain the significance of the slope in a sentence or two below the graph

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