BIO 202 Lecture Notes - Lecture 18: Heterochromatin, Prokaryote, Euchromatin
20 Sep 2016
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1: explain how dna methylation and histone acetylation affect chromatin structure and transcription. Euchromatin and when is highly condensed is heterochromatin and gene expression is silenced. Histone acetylation and dna methylation can regulate chromatin. Histone acetylation is when acetyl groups are attached to loosen chromatin and increase transcription dna methylation is the addition of methyl groups to certain bases reduces transcription and can cause long-term inactivation of genes. Explain how eukaryotic genes can be coordinately expressed and how this contrasts with bacterial operons. Unlike a prokaryotic operon, each gene in eukaryotes has its own promoter and control elements. This control elements are found in enhancers that make sure transcription only occurs when activator proteins are present. Explain how small non-coding rna molecules can affect gene regulation by altering transcription, mrna stability, and translation. Initiation of translation is when mrna can be blocked by regulatory molecules that bind to it.
