Gene Expression Mechanisms and Regulation

The video tutorial by Professor Dave explores how cells regulate gene expression. It begins with an overview of chromosomes and phenotypes, then delves into the molecular processes of transcription and translation. The tutorial explains regulatory mechanisms, including feedback inhibition and operons in bacteria, using E. coli as an example. It also covers complex gene regulation in eukaryotes, highlighting the role of histones, transcription factors, and enhancers. The tutorial emphasizes the importance of understanding these processes for analyzing gene expression and cell specialization.

What is the primary purpose of gene expression in an organism?

• To replicate DNA

• To mutate genes

• To produce proteins

• To divide cells

Which process involves the conversion of DNA to mRNA?

• Mutation

• Transcription

• Replication

• Translation

What is the role of a spliceosome in gene expression?

• To synthesize lipids

• To replicate DNA

• To modify proteins

• To cut out introns from mRNA

How do bacterial cells regulate gene expression through operons?

• By using feedback inhibition

• By acetylating DNA

• By using a promoter and operator system

• By modifying histones

What happens when tryptophan binds to its specific repressor in E. coli?

• The operon is turned on

• The operon is turned off

• RNA polymerase is activated

• The repressor is degraded

Which molecule can deactivate a repressor in the lactose operon of E. coli?

• Glucose

• Galactose

• cAMP

• Allolactose

What is the role of cAMP in positive gene regulation?

• It deactivates repressors

• It binds to DNA directly

• It binds to an activator protein

• It inhibits RNA polymerase

How can histone modification affect gene expression?

• By changing the DNA sequence

• By degrading mRNA

• By altering DNA replication

• By making genes accessible for transcription

What is the function of transcription factors in gene expression?

• To degrade proteins

• To synthesize lipids

• To bind to promoters and enhance transcription

• To replicate DNA

What role do enhancers play in gene expression?

• They inhibit gene expression

• They increase the rate of transcription

• They bind to RNA polymerase

• They degrade mRNA