Lab Report

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BioLab3

Population Ecology Lab Report

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The lab report is unique each semester and checks have been put into place to ensure students are doing their own work. Copying from other students or from outside sources will result in a zero on the accompanying lab quiz.

Introduction

1. Compare the average consumption of an American to someone who lives in Mexico.

1. Population Growth

1. Go to the lab, Section I, Exercise 1 and formulate a hypothesis for the investigation related to natural population growth. What do you predict will happen to the number of yeast cells as they multiply over a period of time?

1. Enter the number of yeast cells shown in the online lab for each time interval in the table below.

1. Total the columns and divide by 5 to determine the average number of yeast cells for the samples. Reminder: all average counts after 15 hours must be multiplied by 10 to account for the dilution factor.

1. Construct a line graph of the average yeast population density at 3-hour intervals. Sign, date and prepare an image of your graph and include it with this lab report.

1. When are the yeast cells multiplying most rapidly? How much time is needed for the population to double?

1. In Lab, Section I, Exercise 2 you will complete an activity pertaining to theoretical population growth. Fill in the table below by doubling each population to find each population size. Use the formula Y = 2 x-1 where Y is the population size and X is the generation. For example, 20 = 1.

1. Construct a line graph of theoretical population growth by plotting generation on the X-axis and population size on the Y-axis. Sign, date and prepare an image of your graph and include it with this lab report.

1. How does the shape of the actual population growth curve compare to the theoretical growth curve?

1. Population Dynamics

1. Differentiate between population growth and theoretical growth.

1. Based on Lab, Section II, Exercise 3, if dad and mom (first generation) have two children (second generation), how many descendants will be in the following eight generations if each child has the same number of children as their parents (22)? Complete the table, then construct a line graph. Sign, date and prepare an image of your drawing and include it with this lab report.

1. A second family includes dad, mom, and four children. How many descendants will be in the following eight generations if each child in each generation has 4 children? Calculate the family size for each generation, then construct another line graph. Sign, date, and prepare an image of your graph and include it with this lab report.

1. Carrying Capacity

1. What is carrying capacity?

1. Describe three factors that could influence the carrying capacity of a song bird population.

IV. Technology and the Ecosystem

1. Based on Lab, Section IV, Exercise 5, describe how environmental zones of the area contributed to ecological stability.

1. If you had been the mayor of this village, what would you have done?

Summary Questions

1. What is the difference between theoretical and actual population growth?

1. What factors stabilize population size?

1. How does a dilution make cell counting easier and more accurate?

1. Suggest ways to limit human population growth.

1. Suggest ways to increase the carrying capacity of the yeast cultures.

1. Suggest ways to reduce growth rate of the yeast cultures.

1. Explain why the human population has increased dramatically.