Transcription

• What happens to the dna in transcription ?

  It does not leave the nucleus

  One strand of the dna acts as a template for production of mrna carries info needed for protein synthesis from nucleus into the cytoplasm

  Ribosomes on the cytoplasm provides surface fir attachment of mrna and assembly of protrins
• what is transcription ?

  process of building mrna
• since RNA hasn’t got thymine what does Adenine bind to ?

  Uracil
• What does the enzyme helicase do?

  Breaks hydrogen bonds between bases in a specific region of dns molecule

  Causes tel strands to unwind and separate exposing nucleotide bases
• What does enzyme polymerase do?

  binds to the template strand of the dna at the beginning of the sequence to be copied
• What happens in transcription ?

  -free rna nucleotide align opposite template strand ,based on the complemtary relationship between bases in dna and free nucleotide

  -rna polymerase moves along the dna forming bonds that add RNA nucleotide one at a time to the growing strand

  -results in synthesis of molecule of MRNA alongside unwound portion of dna .Behind RNA polymerase dna strands rewind to reform double helix

  -RNA polymerase separates from template strand when reached a stop signal

  -production of transcription complete