You Have Performed the Following Mating Experiment Using Hfr and F-Strains

question 78

Multiple Choice

You have performed the following mating experiment using Hfr and F-strains of Escherichia coli: Hfr (thr⁺ leu⁺ gal⁺ strˢ) × F⁻ (thr⁻ leu⁻ gal⁻ strʳ) . Which of the following selective media would you use to score recombinant colonies?

• A) minimal medium
• B) minimal medium + streptomycin
• C) minimal medium + threonine
• D) minimal medium + streptomycin + threonine

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Definitions:

Phospholipids

A type of lipid molecule that is a major component of the cell membrane, consisting of a phosphate group, a glycerol backbone, and two fatty acid tails.

Plasma Membrane

The biological membrane that separates the interior of all cells from the outside environment, protecting the cell and controlling movement of substances in and out.

Hydrophobic Region

A part of a molecule that is repelled by water and tends to be nonpolar.

Phospholipids

A class of lipids that are a major component of all cell membranes, essential for cellular function.