Suppose That a Researcher Is Looking for Met^- Strains of E

question 10

Multiple Choice

Suppose that a researcher is looking for met^- strains of E. coli. She compares two plates. One plate has colonies growing on complete media. The other plate has colonies growing on methionine-deficient media. How can the researcher determine which colonies are met^-?

• A) by replica plating the plate with minimal media onto one with complete media
• B) by streaking all individual colonies on minimal media
• C) by replica plating the plate with complete media onto one with minimal media
• D) by growing the bacteria in broth media that is complete

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Definitions:

Fossil Shells

Remnants of the hard protective outer layer of once-living aquatic organisms, which have been preserved in the Earth's crust over geological time.

Dry Climate

A type of climate characterized by low precipitation levels, leading to desert landscapes and sparse vegetation.

Isotopes

Variations of a chemical element that have the same number of protons but different numbers of neutrons in their nuclei.

Ancient Rock

Rock formations dating back millions of years, often providing information on the Earth's geological and evolutionary history.