Briefly explain why biologists use sampling, rather than counting all members of the population of interest.

1. Briefly explain why biologists use sampling, rather than counting all members of the population of interest. (5 points)
2. When using random sampling techniques, which type of dispersion is most effective? In other   words, which dispersion model will give the most accurate estimation of population size? (2 points)
3. Briefly explain why this would be the case. (4 points)
4. In a forest that measures 5 km by 5 km, a sample was taken to count the number of silver maple trees. The number of trees counted in the grid is shown below. The grids where the survey was taken were chosen randomly. Determine how many silver maple trees are in this forest using the random sampling technique. (5 points)

 7       3   5 11 9       

1. Refer to the diagram below of two plots that are 2 m x 2 m samples from two different 100 square meter fields (Field 1 and Field 2) to answer the following questions:
2. Which location has the higher population density of weeds? (1 point)
3. Each plot is a 2 m x 2 m sample from two different fields, and each field covers a total of 100 square meters. How many weeds are found in each field? Explain how you were able to determine your results. (4 points)
4. What are five limiting factors that would control the population density of weeds? (5 points)
5. A 5 km x 5 km plot has a weed count of 250 weeds. What would the population density be for the exact same plot six months later with a count of 200 weeds? Show your work. (5 points)
6. What technique would be used to estimate animal populations? Why? (5 points)
7. From the yeast count activity, predict what the population count for yeast would be at 200 hours. Provide an explanation for the population count prediction (e.g. How did you arrive at this count?). (5 points)
8. What is the name of the type of growth yeast exhibit? (5 points)
9. Is yeast an r-selected or K-selected species? Based on the type of selection for yeast, list four factors they exhibit. (5 points)
10. List five factors that influenced the population growth of the yeast in the container. Make sure to include factors with a negative and positive influence, if applicable. (5 points)
11. On day three, half of the yeast population was removed from the container and placed in a second container. An additional 2 grams of sugar were added to each container. Describe what the expected growth rate would be for each container. (5 points)
12. What is the general relationship between population growth and the increase or decrease of resource use? (5 points)
13. Give two examples of density-dependent limiting factors. (4 points)
14. As of this year alone, there have been 410 births and 102 deaths in a population of 1000 giraffes. The number of giraffes who have joined this population are 28 individuals and the number who have left total 39 individuals. What is the growth rate (as a percentage) of this giraffe population? (6 points)
15. (Application): How might the information gained from this lab pertaining to Population Ecology be useful to you, or how can you apply this knowledge to your everyday life as a non-scientist? The application will be graded according to the rubric below. (20 points)