Ans.
Chromatin molecules are made up of DNA and histone proteins. Modification of chromatin structure include covalent, post-translational changes in histone proteins, present in chromation. Acetylation and methylation are two important histone modifications that affect structure of chromatin molecules.
Acetylation involves addition of an acetyl group to histones that increases transcription of DNA by loosen the association between DNA and nucleosome.
Methylation involves addition of a methyl group to histones that results in condensation of chromatin molecule and thus, decreases transcription of DNA.
Both acetylation and methylation are reversible processes.
Many chromatin modifications are genetic, means they can pass from one generation to another generation, called epigenetic modifications.
Thus, options B), C), D), E), and F).
<span>A change that increases an organism's chances of survival is called an adaptation. </span><span>An adaption is any inherited characteristics that increase an organisms chance of survival. It is the way organisms </span><span><span>response to the imposed conditions. The characteristics can be structural, behavioral or physiological. </span>Adaptations may include changes in habitat, genetic changes, mimicry, internal adaptations...</span>
The answer is "Vacuole". I hope this help!
Answer:
irreversible chemical change
Explanation:
A chemical change always results in a new substance and as it is not possible to reverse it, it is an irreversible chemical change.
I hope you understood :)