Organelle containing a cell’s genes and controlling its activities.
zona pellucida
Fine granular coat composed of mucopolysaccharides covering the egg; it allows a single spermatozoon to penetrate the egg, which then becomes impermeable to others.
cytoplasm
Clear gelatinous substance surrounding the various cellular structures.
nucleolus
Small spherical body located inside the nucleus, within which the ribosomes, or protein-synthesizing structures, are produced.
corona radiata
Collection of granular cells that forms a protective crown around the egg.
