Answer:
The DNA strands are not free in the nucleus, but forming a compact structure called chromatin along special proteins, known as histones. The chromatin structure has an important role in gene expression, as the level of compaction and the histone modification act as signals for the transcription machinery
In order to be transcribed, different areas in the genome need to unfold from the histone proteins, so the RNA polymerase can access the DNA.
That means, <u>that DNA sequences that transcribe at high rate, are more often unfold from the histones, and more exposed to other proteins to bind them. Particularly, those areas are more sensitive to the attack of endonucleases, such as DNAse I.</u>
As a consequence, an assay of DNAse I digestion can be used to identify highly sensitive or resistant to DNAse cleavage areas in the genome, and therefore serve as an insight to which sequences are more and less transcriptionally active.
Answer:
2 & 4
Explanation:
The theory of spontaneous generation stipulated that life emanated spontaneously from ‘nothing’. This was believed to be true until Francesco Redi & Luis Pasteur later falsified this theory using an experiment. He had two plates of cooked meat. He covered one with a glass bowl and left the other open. The plate with a bowl did not develop maggots while the open one did. This showed that maggot was as a result of hatched eggs that were deposited by flies. Life, therefore, emanates from life.
Explanation:
This statement is correct because the concept of integrating body and mind in physical activity was responsible for the expansion of physical activity, in addition to activities that promote only the well-being of the body aesthetically, but as a set of activities responsible for improvement of health, intelligence, emotional, creativity, as well as an instrument of social integration. The practice of physical activity releases endorphins in the brain, which is a natural substance produced by the brain that is associated with well-being, mood and joy, and this effect occurs during and after physical activity.