Gene Regulation and Expression

How are prokaryotic genes regulated?

• Using homeotic genes

• Through the TATA box

• By the organization of genes into operons

• By environmental factors

What happens when lactose is not present in the medium for the lac operon?

• RNA polymerase begins transcription

• Regulatory proteins bind to DNA and block transcription

• Lactose diffuses into the cell

• The lac genes are activated

What is a key feature of a typical eukaryotic gene?

• It contains a TATA box

• It has a promoter and an operator

• It is regulated by lactose

• It is organized into operons

What role do transcription factors play in eukaryotic cells?

• They control the expression of genes by binding DNA sequences in regulatory regions

• They bind to the O region to block transcription

• They regulate genes by controlling transcription in prokaryotes

• They attach to lactose to change its shape

How do environmental factors influence gene regulation?

• Through the use of homeotic, homeobox, and Hox genes

• By changing the shape of repressor proteins

• They can affect gene regulation

• By affecting the organization of genes into operons