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For each of the E.coli strains shown below, indicate whether production of functional β-galactosidase is constitutive (enzyme is made all the time), inducible (enzyme is only made when lactose is present) or inactive (functional enzyme is not present under any condition).    Definitions: I+ : wild-type lac repressor I- : non-functional lac repressor Is : super-repressor that cannot be removed from the operator under any circumstances O+: wild-type operator OC: mutant operator that cannot be bound by any repressor (not even the super-repressor) Z+: wild-type gene for β-galactosidase Z- : mutant gene for β-galactosidase that produces a non-functional enzyme   Please watch your spelling!   Write inducible, constitutive or inactive in the boxes next to strain information.     plasmid I+ OC Z- / chromosome I- O+ Z+       [1]          plasmid IS OC Z- / chromosome I- O+ Z+       [2]      plasmid I+ Oc Z+ / chromosome I+ O+ Z+     [3]       plasmid I+ O+ Z+ / chromosome I- O+ Z+    [4]       plasmid IS O+ Z- / chromosome I+ OC Z+  [5]   

DNA methylation at CpG dinucleotides

Methylation of DNA at CpG islands

Questions 21-25. The following chromatin modifications tend to INCREASE rates of transcription:

Both enzymes require a primer

Capping factors bind when it is dephosphorylated

Both enzymes use the same nucleotide triphosphates as substrates

RNA polymerases transcribe only parts of the DNA, but DNA polymerases copy all the DNA

RNA polymerases do not require a primer, while DNA polymerases do.

requires the step-wise formation of a multi-component complex to initiate