Final answer:
The control of gene expression in yeast cells can be achieved using a promoter. The promoter region binds transcription factors that control the initiation of transcription, allowing researchers to control when the gene is expressed.
Step-by-step explanation:
The control of gene expression in yeast cells can be achieved by using a promoter. The promoter region is responsible for binding transcription factors that control the initiation of transcription. By manipulating the promoter sequence, researchers can control when the gene is expressed. Other elements like enhancers, terminators, and operators also play roles in gene regulation, but the promoter is specifically responsible for controlling gene expression.