The Phylogenetic Trees of the NifH and SSU RRNA Genes

question 23

Multiple Choice

The phylogenetic trees of the nifH and SSU rRNA genes are incongruent because

• A) nitrogenase is an anaerobic enzyme.
• B) nitrogenase evolves rapidly.
• C) of horizontal gene transfer.
• D) very few microbes have the nifH gene.

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Definitions:

Units-of-Activity Method

A depreciation method where the expense is based on the number of units produced or the use of the asset, rather than the passage of time.

Double-Declining-Balance

An accelerated method of depreciation that doubles the normal depreciation rate to expense the asset more quickly.

Estimated Life

The expected duration over which an asset is likely to be useful or productive in its intended operation, used for depreciation purposes.

Straight-Line Depreciation

A method of allocating an asset's cost evenly across its useful life, resulting in the same depreciation expense each year.