BIO206H5 Chapter Notes - Chapter 7.1: Tata Box, Sigma Factor, Ribonucleoside
Document Summary
Flow of information from dna to rna to protein - central dogma of molecular biology. Portions of dna sequence are transcribed into rna. Cells can synthesis large amounts of protein whenever necessary. Rna - linear polymer of four different nucleotides linked by phosphodiester bonds. Single stranded - fold variety of shapes, carry out functions in cells. Transcription produces rna complementary to one strand of dna. Rna chain determined by complementary base-paring with dna template. Does not form hydrogen bonds with dna template strand. Copied from a limited region of dna, few thousand nucleotides long. Can start without primer - not as accurate as dna, mistake every 10^4 nucleotides. Synthesis of the next rna starts before the previous one is finished. Several types of rna are produced in cells. Eukaryotes mrna carry info transcribed for one gene, single protein. Nonmessenger rnas act as regulatory, structural, and enzymatic components, play key parts in translation of protein.
