HTHSCI 1LL3 Lecture Notes - Lecture 10: Polynucleotide, Operon, Low-Density Lipoprotein

• School: McMaster University
• Department: Health Sciences
• Course: HTHSCI 1LL3
• Professor: Teresa Mccurdy

Document Summary

Rna synthesis from a dna template is called transcription . This process uses a polymerase that joins nucleotides to form a single strand. The difference between the sequence in the rna strand and the dna coding strand is that uracil (u) takes the place of thymine (t) in rna. Dna is opened, machinery will copy one strand because rna has only one strand. Rna polymerase will copy template strand, joining the nucleotides. The polynucleotide strand is synthesized similar to dna, in the 5" 3" direction (copied from the template strand in the 3" 5" direction) The big difference between rna and dna polymerases is the ability of rna polymerase to initiate synthesis. A primer is not needed by rna polymerase; another difference is the lack of a separate proofreading exonuclease. Rna is transient, therefore no mutations occur because of the degradation. Rna will code for protein in the cytosol, then will be degraded speed.