Chromatin structure can increase or decrease transcription of a gene according to the:
A. combination of amino acid modifications in the histone tails.
B. coding sequences in the messenger RNAs for histone proteins.
C. combination of histone proteins found within the nucleosome.
D. proportion of arginine and lysine amino acids in the histone proteins.

D. proportion of arginine and lysine amino acids in the histone proteins.

Explanation:

Epigenetic modifications are one of the main reasons of methylation and de-methylation, acylation and de-acylation of histone proteins that trigger the transcriptional process. All of these mentioned modification causes the change in the ration of lysine and arginine residues and these are the main reasons that affect the structure of chromatin as required.

"a scientist studying a whale and its surroundings would need to understand the structure of atoms in case something was negatively affecting the whale or its surroundings."

explanation:

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