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Ajax Seed Company
Task with Student Directions
Contributed by: New York State Alternative Assessment in Science Project (NYSED)

Task: At this station, you will be analyzing the genetic characteristics of some hypothetical seeds.

Ajax Seed Company has bags of seeds for sale that "guarantees that all of the plants produced from this bag of seeds will be tall." A farmer planted seeds from one of these bags and found that all of the seeds that germinated grew into tall plants.

The farmer collected the seeds from many of these tall plants when he planted the collected seeds the following year, some of the new plants were tall while the others were short.

Note:   If symbols are used in your responses, a key must be provided.

  1. What are all the possible genotype crosses that the Ajax Seed Company could have used to produced the first bag of seeds?

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    Explain your answer, using complete sentences.

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  2. What are the possible genotype(s) of the seeds in the bag that the farmer bought?

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    Explain your answer, using complete sentences.

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  3. Using complete sentences explain how the collected seed could produce both tall and short plants.

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  4. The farmer wants to produce a pure breeding line of tall plants. Each year he collects seed only from tall plants. The following summer, he plants the collected seeds. After five years of doing this, can he guarantee that all the collected seeds will result in tall plants?

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    Explain your answer, using complete sentences.

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