A very large gene, such as DMD, may take hours to transcribe mainly because
a. RNA polymerase may have difficulty clearing the promoter.
b. long mRNAs form secondary structures that interfere with transcription.
c. RNA polymerase has time-consuming error correction activity.
d. many histone octamers may need to be modified or disassembled.
e. there may be multiple abortive attempts at transcription.
Ans: d
You might also like to view...
DNA polymerase III
A. synthesizes an RNA primer. B. is needed for adding nucleotides during mRNA synthesis. C. synthesizes new DNA only in the 5' to 3' direction. D. cannot add nucleotides to the lagging strand.
What was the perceived fundamental conflict between Darwin's and Mendel's theories?
a. Darwin was a scientist while Mendel was a monk. b. Mendel's experiments were unbiased, while Darwin set out to prove evolution by natural selection. c. Mendel's experiments were based on simple traits while Darwin's evidence was based on complex characteristics. d. Mendel's theory was based on experimentation while Darwin's was based on observation.
Why must T cell activation take place outside the thymus?
A. An activated T cell could destroy the other maturing T cells. B. Many T cells are self-reactive and must be eliminated in the thymus before any possibility of activation. C. An activated T cell could then destroy the thymus gland itself. D. Other cell types might be accidentally activated in the thymus.
Match the layers of a pericarp with their correct description.
A. mesocarp B. exocarp C. endocarp