Adding acetyl groups to a histone regulates gene expression by allowing transcription to proceed by
a. increasing the pH of the cell.
b. loosening the DNA wound around the histone.
c. modifying the nucleotides of the promoter region of the DNA molecule.
d. enhancing the activity of RNA polymerase.
e. enhancing the development of a DNA-RNA hybrid.
ANSWER: b
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The type of skeleton that consists of fluid constrained within a layer of flexible tissue is a(n)
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What is a fruit species that can be propagated by apomixis?
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