When Researchers Examined the Effects of Withholding Nitrogen from Bradyrhizobium

question 13

Multiple Choice

When researchers examined the effects of withholding nitrogen from Bradyrhizobium japonicum, they used a "split root" treatment in which half of a soybean plant's root mass received gaseous nitrogen, whereas the other half did not. Why did the researchers use this split-root treatment?

• A) They were economizing on experimental soybean plants.
• B) They were testing whether different parts of the root react differently to the absence of nitrogen.
• C) They were testing the range of nitrogen in which soybean plants can thrive.
• D) They were testing whether the potential "retaliation" against cheating symbionts was specific to root nodules that did not fix nitrogen.

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Definitions:

Avoidant Attachment

A type of insecure attachment style characterized by a desire to maintain independence and emotional distance from others.

Distressed

Experiencing anxiety, sorrow, or pain; often a response to stressful situations or challenges.

Reunion

The act of coming together again after a period of separation.

Ambivalent/Resistant Attachment

A type of insecure attachment pattern observed in some children, characterized by distress when separated from caregivers and ambivalence upon their return.