Answer:
The positive charge of the histone proteins get reduced due to the process of histone acetylation, thus making the wrapping of DNA around the histones less tightened. The loose connected DNA afterward associates with the transcription factors for the articulation of the genes situated in that area.
Generally, when there is no requirement of gene anymore, the acetyl groups from the histones get withdrawn by the activity of histone deacetylase enzyme (HDAC9) that makes the DNA tightly wrapped and inaccessible again. In case, when less expression of histone deacetylase enzyme occurs, the process of deacetylation fails to take place. This indicates that within an immune cell, at the time of infection, the inflammatory gene, which was made available does not get re-wrapped firmly around the histones.
Answer:
Crust, mantle and core.
Water availability.
Volcanic eruptions.
Explanation:
The main similarities about Early earth and Modern earth is their layers of soil such as crust, mantle and core means that the both Early earth and Modern earth are made up of these three layers. At that time water is present in huge amount while on the other hand, in Modern earth water is also present in large amount as compared to land. Volcanic eruptions occurs in both early and Modern earth.