The Following Questions Refer to Figure 27.1

question 3

Multiple Choice

The following questions refer to Figure 27.1.
In this eight-year experiment, 12 populations of E. coli, each begun from a single cell, were grown in low-glucose conditions for 20,000 generations. Each culture was introduced to fresh growth medium every 24 hours. Occasionally, samples were removed from the populations, and their fitness in low-glucose conditions was tested against that of members sampled from the ancestral (common ancestor) E. coli population.

Figure 27.1
-Which term best describes what has occurred among the experimental populations of cells over this eight-year period?

• A) microevolution
• B) speciation
• C) adaptive radiation
• D) sexual selection
• E) stabilizing selection

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Definitions:

Total impedance

The overall resistance to the flow of alternating current, combining the effects of resistances, inductive reactance, and capacitive reactance in a circuit.

Applied voltage

The external voltage applied across a component or circuit, causing electric current to pass through it.

Circuit

A closed path through which electric current flows or may flow.

Reactive Power

The portion of electricity that establishes and sustains the electric and magnetic fields in AC operations, measured in volt-amperes reactive (VAR).