Answer to Question 1ANS: B
Photosynthesis occurs in the euphotic zone. It can be limited by the lack of light but also the
overexposure to light. It overwhelms the photosynthetic chemistry of some autotrophs. Information
can be found in the section Lack of Nutrients and Light can Limit Primary Productivity.
Answer to Question 2ANS: C
Iron becomes the limiting factor in many open water areas that have all the other necessities for
photosynthesis. Photosynthetic autotrophs only require four main ingredients for success: sunlight,
water, carbon dioxide, and inorganic nutrients. Information can be found in the section Lack of
Nutrients and Light can limit Primary Productivity.