An Operon Is

question 129

Multiple Choice

An operon is

• A) a molecule that can turn genes on and off.
• B) an inducer bound to a repressor.
• C) a series of regulatory sequences controlling transcription of protein-coding genes.
• D) any long sequence of DNA.
• E) a promoter, an operator, and a group of linked structural genes.

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Definitions:

Zona Pellucida

A thick, transparent coating surrounding an oocyte (egg cell) and early embryo in mammals, playing a key role in fertilization by allowing sperm binding and inducing the acrosome reaction.

Vitelline Envelope

An acellular covering of the eggs of certain animals (e.g., echinoderms), located just outside the plasma membrane.

Granulosa Cells

The somatic cells in the ovary that surround developing female gametes (oocytes) and are involved in hormone secretion and oocyte maturation.

Haploid Chromosome

A set of chromosomes that is half the full set of genetic material, typical of gametes, where each cell contains one complete set of chromosomes.