Transcription

general
	mRNA is made using DNA as a template(pattern)
	sequence of bases
		triplets- set of 3 nucleotides in DNA
		codon- set of 3 nucleotides in mRNA
		anticodon- set of 3 nucleotides in tRNA
steps
	1.	DNA unwinds
	2.	DNA unzips
	3.	RNA polymerase bonds to a promoter region of the DNA
	4.	new complementary RNA nucleotides are bonded to DNA's exposed bases
	5.	mRNA nucleotides are bonded together to form a strand
	6.	mRNA pulls away from DNA
	7.	mRNA passes through a nuclear pore into the cytoplasm
	8.	in eukaryotic cells, DNA has non-coding sections called introns and coding sections called exons. the introns must be cut out of DNA
	9.	mRNA always starts with an initiator codon which is AUG and ends with one of three stop codons: UAA, UA, UGA
Enzymes involved
	helicases- unwind and unzip DNA
	RNA polymerase
		bonds to promoter region
		bonds RNA nucleotides to the exposed bases of DNA
	ligase- bonds the RNA nucleotides together to form a strand

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