Nucleotide excision repair in human cells. 

A DNA lesion that causes distortion of the double helix, such as a thymine-thymine dimer, is initially recognized by a complex of the XP-C (xeroderma pigmentosum C protein) and 23B proteins.

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#Id: 5689

#Unit 7. System Physiology – Animal

TLS Online TPP Program

#Id: 2959

#Unit 3. Fundamental Processes

A nucleus injected into a Xenopus egg can replicate only once unless the nuclear membrane is permeabilized to allow subsequent replication cycles

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#Id: 2940

#Unit 3. Fundamental Processes

Note that a crudal difference between replication in bacteria and replication in eukaryotes is that in bacteria replication is occurring on DNA, while in eukaryotes replication is occurring on chromatin and nucleosomes play a role so their presence must be taken into account.

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#Id: 2513

#Unit 13. Methods in Biology

Larger fragment DNA are isolated by using agarose gel while shorter fragment are separated by 3.5% polyacrylamide gels are used to separate DNA in the range 80–1000 nt and 12% gels to resolve fragments of between 20 and 100 nt.

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#Id: 5988

#Unit 10. Ecological Principles

Ecosystem exploitation hypothesis