The closed complex is converted into an open complex of 1.3 turns of the double helix in a series of steps by first “melting” a short region of DNA. 

This Isomerization is essentially irreversible and, once complete, typically guarantees that transcription will subsequently initiate.

TLS Online TPP Program

#Id: 5437

#Unit 7. System Physiology – Animal

The Na+ channels rapidly enter a closed state called inactivated state and remain in this state for a few milliseconds

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#Id: 1843

#Unit 3. Fundamental Processes

The α-amanitin binding site is beneath a “bridge helix” extending across the cleft between the two largest pol II subunits, Rpb1 and Rpb2

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#Id: 2277

#Unit 3. Fundamental Processes

Core enzyme without the s subunit could not transcribe viral DNA, yet had no problems with highly nicked calf thymus DNA

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#Id: 9405

#Unit 11. Evolution and Behavior

Costs & benefits of territorial defense

Cost

Defending a territory requires time & energy and may, if aggressive defense is  needed, may pose some risk of injury.

Benefits‐

The improved access to resources represents  the 'benefit(s)' of territory defense.

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#Id: 7061

#Unit 3. Fundamental Processes

Changes in the genetic code in bacterial or eukaryotic nuclear genomes usually assign amino acids to stop codons or change a codon so that it no longer specifies an amino acid.