Molecular Biology Module 3: Transcription

Shown is Gene Y. +1 marks the start of transcription. Open boxes are introns. Filled boxes are untranslated (grey) and coding (black) exon sequence. Gene Y is

	1. a eukaryotic protein-coding gene
	2. a prokaryotic protein-coding gene
	3. a eukaryotic tRNA gene
	4. not possibly categorised from the information given
	5. a prokaryotic tRNA gene

	a. mRNAs bearing mutations are usually degraded before they can be translated
	b. The errors occurring during RNA synthesis are repaired later.
	c. The copies are not incorporated into the genetic material of the next generation.
	d. RNA molecules are smaller than DNA molecules.
	e. Errors introduced into protein sequence usually have no effect on function.