Practice_Exam_III_Key

Practice_Exam_III_Key - Name_Francis Scott Key_ BIOL 50...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Name__Francis Scott Key ________________ Student I.D.__A Sharp ____________ BIOL 50 Practice Exam III 1. (3 points each) For each of the following terms, write a single sentence definition or description of function: a. Sigma Factor In E. coli , initiation of transcription requires the sigma subunit (or Sigma Factor) of RNA polymerase. There are different Sigma factors for different sets of genes, and therefore they are used to coordinate transcription of specific sets of genes. Sigma Factors participate in separating DNA strands at the promoter so that RNA polymerase can begin RNA synthesis b. Spliceosome The molecular machinery that remove introns from the primary transcript. The spliceosome contains both proteins and snRNP s, which recognize the splice donors and acceptors. c. enhancer Cis -acting DNA regulatory sequence in eukaryotes; transcriptional activators bind to them to increase transcription. d. intron Segment of a gene that gets spliced out of the primary transcript in making the mRNA. e. Operator A cis -acting regulatory site upstream of prokaryotic genes that contains specific sequences that are bound by regulatory proteins, for example LacI at the Lac operon. Page 1 of 5
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Name__Francis Scott Key ________________ Student I.D.__A Sharp ____________ BIOL 50 Practice Exam III 2. O
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/02/2008 for the course BIOL 50 taught by Professor Staff during the Spring '08 term at UNC.

Page1 / 5

Practice_Exam_III_Key - Name_Francis Scott Key_ BIOL 50...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online