Which of the Following Most Accurately Describes the Preservation of Duplicate

question 4

Multiple Choice

Which of the following most accurately describes the preservation of duplicate genes via the subfunctionalization model?

• A) The ancestral gene performs two different functions, and eventually the two duplicate copies evolve so that one copy performs one function, and the other copy performs the other function; both copies are therefore required for the organism to have optimal fitness.
• B) In order to be favored by natural selection and therefore to increase in frequency, the duplicated copies must evolve so that together they perform the original gene's functions better than the original gene, giving organisms with subfunctionalized genes a fitness advantage.
• C) Subfunctionalization is most commonly a defense against mobile genetic elements. Because subfunctionalized genes separate two functions from an ancestral gene into two separate genes, a mobile genetic element insertion can damage only one of the two functions, not both; therefore, subfunctionalization is favored by natural selection in genomes with a high load of mobile genetic elements.
• D) All that matters for the subfunctionalization model is that together the duplicated genes perform the original gene's function(s) the same or better; even if one gene copy becomes nonfunctional, this still counts as subfunctionalization so long as the other copy performs the original function.

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Definitions:

Straight-Line Depreciation

A procedure for apportioning the cost of a tangible good over its operational lifespan in uniform annual amounts.

Initial Investments

The initial capital outlay required to start a project, purchase assets, or acquire a company, reflecting the upfront costs to begin operations.

After-Tax Discount Rate

The discount rate adjusted for the effects of taxes, used in net present value (NPV) calculations to determine the value of future cash flows after tax.

Income Tax Rate

The percentage at which an individual or corporation is taxed on its income, with the rate often varying based on the level of income.