Answer:
a. methylation at lysine 9 or 27 of histone H3.
Explanation:
Methylation causes the switching off of genes using steric hinderance to prevent access to DNA.
<span> sunlight, little water, air, rock these are some :)</span>
The right answer is the reticular activating system (RAS).
The Reticular Activation System. This is an element of your brain that is useful for capturing your attention and for achieving your goals more easily.
Let's take an example immediately to illustrate what the RAS really means: A loudspeaker announces your name and asks you to pick up your daughter at the reception. And there, your brain, your RAS gets in motion: your attention is at its highest level and you distinctly and clearly distinguish the message and its content addressed to you.
Thus, thanks to the RAS, which starts automatically in your brain, the relevant information is brought to your attention. The RAS plays a role of intermediary, a filter between the conscious part and the unconscious part of your brain. The latter can not store all the information, it is necessary that a relevant sorting is done between them. It's the RAS that does it. It is he who decides what is worthy of attention and what is not. As soon as it judges that information concerns you to the highest degree, he will "wake up" your brain that will absorb it. Thus, as part of our example, the RAS has been instructed to wake up your attention as soon as your name is spoken in the speaker.
I can surely tell you it is super shiny bacon
The pH of solutions is an important chemical property. Oxygen is much more electronegative than hydrogen. Both shared electrons in an oxygen-to-hydrogen bond tend to spend more time with the oxygen atom than with hydrogen. Although the vast majority of water molecules remain intact in liquid water, at any given moment a few individual hydrogen atoms succumb to the pressure of the electronegative oxygen and lose their hold on both shared electrons. When this happens, the covalent bond is broken and a hydrogen ion<span> (positive charge because it lost its electron to oxygen, shorthand = H</span>+<span>) is released. The remaining part of the original water molecule is called a </span>hydroxide ion<span> (negative charge because it kept an extra electron, shorthand = OH</span>-). Although present at very low levels in solution, H+<span> and OH</span>-<span> ions can have enormous effects on the properties of a solution, especially when they are not in balance. In pure water, every hydroxide ion that forms creates a hydrogen ion, so there are equal numbers of anions and cations. If a solute is added to water, however, this balance can change.</span>
