In Studies of the Nitrogen Fixation of Elliott's Milkpea, Researchers

question 23

Multiple Choice

In studies of the nitrogen fixation of Elliott's milkpea, researchers found that increasing carbon dioxide increases nitrogen fixation at first, but then decreases it, even to a level that is below the baseline level. If a program were being designed to maintain high levels of nitrogen fixation, the best course of action would be to add

• A) even more carbon dioxide gas.
• B) more nitrogen gas.
• C) iron, molybdenum, and other micronutrients to the soil.
• D) a combination of oxygen and nitrogen gases.
• E) a competing species.

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Definitions:

Disparity

A significant difference or inequality between two or more elements, often related to conditions or treatment.

Depth Perception

The visual ability to perceive the world in three dimensions (3D) and to judge the distance of objects.

Two-dimensional

Having height and width but no depth, applicable in geometrical spaces or flat surfaces.

Retina

A layer of light-sensitive cells at the back of the eye that captures images and sends them to the brain through the optic nerve.