Answer:
The correct option is <em>B) ultraviolet region, especially below a wavelength of 320 nm.</em>
Explanation:
Ultraviolet light carries an enormous amount of energy in it. It is invisible to the human eye. When UV light with enormous energy and wavelength lesser than 320nm, hits the DNA, it causes changes in the structure of the DNA. Mostly, it affects the thymine nitrogenous base regions and forms pyrimidine dimers. The structure of the DNA changes on all the sites where dimers form and hence, they cannot be properly transcribed.
Answer:
This is through the process of methylation and phosphorylation of histones tails.
Explanation:
The addition of a methyl group to the amino acid of the histones of the nucleosomes that compacted DNA in the nucleus is called mehtylation, while the addtion of phodpahte is phosphorylation
Its effects on gene expression depends on the number of <u> methyl groups, and type of amino acid that methylated. During transcription. </u>
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The DNA double strands are compacted and therefore hidden from transcription factors and enzymes of transcription by the hitones tails of the neuclosomes, Methylation weaken the binding bonds between the tails and DNA structure ; thereby aiding the uncoiling of DNA from the tails.(nucleosomes).This chemical reaction aided DNA strands exposure to transcription factors and enzymes, for initiation of transcription. This explains the dyanmic activity of methylation
Futhermore phophorylation also favours unwrapping of DNA, by imitating modifying enzymes e.g H3Y41E and H3T45E and convert it to→→ H3Y41phopspahte to aid DNA unwrapping and accessibility to transcription factors and RNA polymerase Enzymes,
Answer:
a. Reproduction occurs rapidly
Explanation:
asexual reproduction can occur rapidly, more quickly than sexual reproduction
The respiratory system depends on the nervous system for signals to a - coordinate the muscles that control breathing. Indeed, our nervous system plays a vital role when it comes to many bodily aspects where we don't even appreciate them on a daily basis. They are, however, extremely important.
If the earth didn't rotate, currents would flow in straight lines from pole to equator. :)
