The Following Question Refers to the Figure

question 32

Multiple Choice

The following question refers to the figure.
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.

If the vertical axis of the figure above refers to relative fitness, then which of the following is the most valid and accurate measure of fitness?

• A) number of daughter cells produced per mother cell per generation
• B) average swimming speed of cells through the growth medium
• C) amount of glucose synthesized per unit time
• D) number of generations per unit time

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Definitions:

MTBF Distributions

Mean Time Between Failures distributions, a statistical measure used to describe the expected reliability or availability of a system over time.

Infant Mortality

The failure rate early in the life of a product or process.

Normal Distribution

A probability distribution which is even around the mean, indicating that data points closer to the mean occur more frequently than those further away from the mean.

Maintenance

The process of preserving equipment, machines, buildings, or systems through routine checkups, repairs, and replacements to ensure they remain in a safe and functional condition.