Explain how, when improper base pairing escapes repair by the proofreading system, cells are able to detect and repair mutations

What will be an ideal response?


Improper base pairing distorts the structure of DNA, and repair enzymes scan the DNA and recognize these distortions. Once the distortion is recognized, these repair enzymes cut the DNA strand on either side of the mismatched nucleotide, removing a portion of the DNA strand. DNA polymerase then fills in the gap, and another enzyme closes up the sugar-phosphate backbone.

Biology & Microbiology

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Sexual reproduction decreases the genetic variation of a species

Indicate whether the statement is true or false

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Lisa and Jack Nash obtained compatible stem cells that cured their young daughter Molly's Fanconi anemia by

A) allowing Molly to undergo gene therapy on the affected cells. B) allowing Molly to undergo gene therapy on her germ cells. C) using umbilical cord stem cells from an unrelated donor. D) using umbilical cord stem cells from a younger sibling, who was conceived and selected for this purpose.

Biology & Microbiology

Ribosomes bound to some of the membrane invaginations in the endomembrane theory

a. true b. false

Biology & Microbiology

Compare and contrast DNA Polymerases I, II, and III in E. coli. What capabilities are shared, and which are exclusive to only one type of polymerase?

What will be an ideal response?

Biology & Microbiology