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:

Intraepithelial Lesion

A term describing early changes in the cells of the skin and some mucous membranes that may develop into cancer, usually found in the context of cervical cancer screening.

Epithelial Cell Abnormalities

Irregularities in the cells lining the surfaces of organs and structures in the body, which can indicate disease or cancer.

Gynecology

A branch of medicine that focuses on the health and diseases of the female reproductive system, as well as related issues in other bodily systems.

Lamaze

A program or method of managing labor during birth.