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
You might also like to view...
In early experiments to understand the control of the cell cycle, researchers fused HeLa cells that were at different
stages of the cell cycle. What did the results of these experiments suggest?
a. The concentrations of cyclin dependent kinases (Cdks) fluctuate throughout the cell cycle. b. The concentrations of cyclins fluctuate throughout the cell cycle. c. The cell cycle has three checkpoints through which the cell must pass in order to progress through to mitosis. d. Microtubules play an essential role in the progression of the cell cycle. e. Molecules in the cytoplasm control the progression of the cell cycle.
The type of skeleton that consists of fluid constrained within a layer of flexible tissue is a(n)
A. vascular canal. B. endoskeleton. C. gastrovascular cavity. D. exoskeleton. E. hydrostatic skeleton.
How are fossils older than 60,000 years dated?
a. directly dating the fossil with carbon 14 b. directly dating the fossil with uranium 238 c. dating rock formations below the fossil d. dating rock formations above the fossil e. dating rock formations above and below the fossil
What is a fruit species that can be propagated by apomixis?
a. apple b. peach c. citrus d. pear e. peach