Founder effect or population bottleneck refer to events which bring about reduction in the genetic variability of a particular specie population. Such events typically drastically reduce the gene pool of the population and produce a smaller number of population with less genetic diversity. An example of a population bottleneck is a genocide event. Such event will destroy a large percentage of the affected population leaving only a smaller population with less genetic diversity. i hope these helps.
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Generally, when there is no requirement of gene anymore, the acetyl groups from the histones get withdrawn by the activity of histone deacetylase enzyme (HDAC9) that makes the DNA tightly wrapped and inaccessible again.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.
Water would enter and exit the cell at the same rate so the answer to this question is letter B
