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Tufts OpenCourseware
Authors: Kathleen Merrigan, Ph.D., William Lockeretz, Ph.D.
Color Key
Important key words or phrases.
Important concepts or main ideas.


  1. What is the difference in how hereditary information is stored in male and female plant gametes? (15 points)

    1. Give an example of why this difference is important in plant breeding. (10 points)

  2. Define denitrification . (15 points)

    1. What is its environmental significance? (10 points)

  3. You find yourself at a cocktail party. The center buffet table holds the following savory treats: tortilla chips, tomato salsa, endive leaves stuffed with blue cheese, smoked salmon, capers, rice, sautèed squash, and papaya soaked in brandy. The bar offers the following beverages: wine, coke, milk, orange juice, and beer. Yummy.

    1. Circle the food and drink items that may be genetically engineered as of this date (meaning that they are commercially available, not just in the lab). (5 points)

    2. If you could pick one menu item to eliminate because of environmental concerns related to GMOs and the environment, which would it be and why? (There can be more than one right answer.) (20 points)

  4. Dennis Avery argues that organic food is unsafe because it exposes consumers to E coli 0157. Is there any validity to his argument?