Name:

Period:

Graphing Activity #1

Exponential and Logistic Growth

Introduction:

Populations can change due to a variety of factors: birthrate, death rate, immigration (moving into an area), emigration (moving away from an area), space and resource availability, etc. A population grows from having a higher birth rate than death rate, having more immigration than emigration or a combination of the two. On Earth there are two different types of population growth: Exponential Growth, when an organism reproduces at a constant rate, and Logistic Growth, a more realistic growth pattern that occurs when the population is leveled off following Exponential Growth due to a finite, or limited, amount of resources. This maximum amount of individuals that can live in a particular area is known as Carrying Capacity.

Activity:

With this information, it is your job to plot the data tables of population growth information given to you ontoline graphs (one graph for each data table). You will then determine whether each graph is an example of Exponential Growthor Logistic Growth. Remember to label your graphs, including TITLE, X-AXIS, Y-AXIS

Example:

Part I: Yeast Growth in a 10 Hour Time Period

# Bacterial Cells / 2 / 200 / 600 / 1000 / 1050 / 1045
Time (Hours) / 0 / 2 / 4 / 6 / 8 / 10

Part II: Rabbit Growth in a 250 Year Time Period

#
Rabbits / 10 / 15 / 30 / 90 / 250 / 700
Time (Years) / 0 / 50 / 100 / 150 / 200 / 250

Post-Activity Questions(on a separate sheet of paper):

  1. This yeast population growth data that you are given is an example of which pattern of population growth: Exponential or Logistic? How do you know? Describe the curve of the line graph.
  1. The rabbit growth data that you are given is an example of which pattern of population growth: Exponential or Logistic? How do you know? Describe the curve of the line graph.
  1. Do you think the Exponential Growth example will continue to grow at this constant rate? Why or why not?
  1. For the Logistic Growth example, what appears to be the Carrying Capacity (estimate)? How do you know this?
  1. Describe a scenario, or situation, where Exponential Growth could happen forever? Would this be a good thing for our planet?