In E Coli When Tryptophan Is Present in the Environment

question 3

Multiple Choice

In E. coli when tryptophan is present in the environment,

• A) the tryptophan operator will break down tryptophan.
• B) the tryptophan-repressor protein will be unable to bind to the tryptophan operator.
• C) tryptophan will bind to a repressor protein.
• D) the tryptophan-repressor protein will be unable to bind to tryptophan.

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Definitions:

Ctenophores

Phylum of marine animals (comb jellies) whose bodies consist of two layers of cells enclosing a gelatinous mass. The outer surface is covered with comblike rows of cilia, by which the animal moves.

Nematocysts

Specialized cells in cnidarians (like jellyfish) that shoot out a toxic barb in self-defense or to capture prey.

Biradially Symmetrical

A type of symmetry in organisms where the body can be divided into mirror-image halves in two different planes.

Cnidarian

A group of aquatic invertebrates known for their stinging cells, including jellyfish, corals, and sea anemones.