The division of a bacterium into two daughter cells is accomplished by the formation of a septum.

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#Id: 4712

#Unit 13. Methods in Biology

The electronic transitions of the peptide bond occur in the far UV. The intense peak at 190 nm, and the weaker one at 210–220 nm is due to the p!p* and n!p* transitions.

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#Id: 7786

#Unit 2. Cellular Organization

NLSs were first discovered through the analysis of mutations of the gene for large T-antigen encoded by simian virus 40 (SV40).

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#Id: 3056

#Unit 10. Ecological Principles

Larger populations are more resistant to extinctions.

Greater ranges of habitats promote increased speciation rates.

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#Id: 5448

#Unit 7. System Physiology – Animal

During the refractory periods, excitable cells are incapable of producing normal action potentials

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#Id: 6419

#Unit 2. Cellular Organization

When arabinose is present, AraC binds that sugar and adopts a configuration that allows it to bind DNA as a dimer to the adjacent half-sites, araI1 and araI2). 

Just upstream of these is a CAP site: in the absence of glucose, CAP binds here and helps activation.

In the absence of arabinose, the araBAD genes are not expressed. This is because when not bound to arabinose, AraC adopts a different conformation and binds DNA in a different way: one monomer still binds the araI1 site, but the other monomer binds a distant half-site called araO2.