Unit 8 FRQ (Invasive Species)

AP Bio Free Response Question for Invasive Species

👋 Welcome to the AP Bio Unit 8 FRQ (Invasive Species). These are longer questions, so grab some paper and a pencil, or open up a blank page on your computer. 

⚠️ (Unfortunately, we don't have an Answers Guide for this question, but it can give you an idea of how an FRQ for Unit 8 might look on the exam.)

⏱ The AP Biology exam has 6 free-response questions, and you will be given 90 minutes to complete the FRQ section. (This means you should give yourself ~15 minutes to go through each practice FRQ.)

• • 🤔 Need a quick refresher of the unit as a whole? Check out the Unit 8 Overview
• • 😩 Getting stumped halfway through answering? Look through all of the available Unit 8 resources

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Setup

Crepe myrtles, or Lagerstroemia, are popular trees used in landscaping because of their quick growth and aesthetically pleasing foliage in the spring. They are also extremely fast-growing and resistant to most diseases. Crepe myrtle bark scale, or CMBS, is a type of insect that infects crepe myrtles. It has a felt-like gray surface and bores into crepe myrtles to consume the sap, and excretes black waste that covers the bark of the trees. Despite the fact that it was only first spotted in Dallas, Texas in 2004, it spread to neighboring states, including Arkansas and Tennessee, by 2014 and 2013, respectively. This rapid growth does not appear to be slowing down. 

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Questions

(a) Identify the type of growth CMBS are currently experiencing across the southern United States. 

(b) Describe the relationship between the crepe myrtle trees and CMBS. 

(c) On a half acre lot of land, there is an estimated population of 1467 CMBS. The per capita birth rate over one month is 0.14, and the per capita death rate is 0.06. Calculate the per capita growth rate of the population? Round your answer to the nearest hundredth. 

(d) Neonictinoids are insecticides that can be placed on the ground around CMBS infestations because trees and plants will absorb the substance into its vascular system. Identify the property of water that allows neonictinoids to be absorbed, and describe the change in the type of growth of CMBS you would expect to see shortly after. 

(e) A neighboring lot of land has Simpson’s diversity index of 0.74. The lot infected by CMBS has a Simpson’s diversity index of 0.49. Explain what this difference in indexes means. 

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