The Phylogenetic Trees of the NifH and SSU RRNA Genes

question 3

Multiple Choice

The phylogenetic trees of the nifH and SSU rRNA genes of nitrogen-fixing bacteria are incongruent because

• A) nitrogenase is an anaerobic enzyme.
• B) this is a characteristic of all enzyme genes.
• C) of horizontal gene transfer.
• D) very few microbes have the nifH gene.

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Definitions:

Proactive Interference

A phenomenon where older memories interfere with the recall of newer memories.

Retroactive Interference

A phenomenon where newly acquired information interferes with the recall of information learned previously.

Memory Problems

Difficulties in remembering information, which can range from minor forgetfulness to more serious conditions affecting daily life.

State-dependent Memory

The phenomenon in which information learned in a particular state of mind (e.g., emotional, pharmacological) is more easily recalled when in the same state.