Ruggles Gates reviewed present knowledge regarding nuclear structure ... Gates believes that the nucleolus contains two substances, one of which enters the chromosomes in prophase and leaves ...

Prokaryotes are organisms whose cells lack a nucleus and other organelles ... which is not surrounded by a nuclear membrane. Many prokaryotes also carry small, circular DNA molecules called ...

The secret to cellular youth may depend on keeping the nucleolus—a condensed ... an artificial way to secure rDNA to the membrane surrounding the nucleus of yeast cells so they could control ...