How Does Comparative Data on Genes of Extant Species Help

question 9

Multiple Choice

How does comparative data on genes of extant species help us to make estimates of what happened before the phylogenetic event horizon?

• A)Common genes must have existed for a long time.
• B)If the first life-forms consisted of RNA, then current RNA-coding genes must be the ancestral genes.
• C)Common functional genes imply the minimal characteristics of early cells.
• D)Because so many small genome bacteria are endosymbionts, the earliest cells must have been endosymbionts.

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Definitions:

Progressive

Referring to a tax system in which the tax rate increases as the taxable amount increases, leading to higher earners paying a higher percentage of their income in taxes.

Regressive

A term often used to describe a tax system where the tax rate decreases as the taxable amount increases, effectively placing a greater burden on those with lower incomes.

Benefits-Received Principle

An approach to funding public goods and services where payments are made by those who benefit from them, matching payment to benefit received.

Tax System

The organized method by which a government collects taxes from its citizens and businesses to fund public services and infrastructure.