Answer:
option 3
Explanation:
In non-homologous end joining, the break ends are directly ligated together without the need for a homologous template unlike the homologous repair. this form of repair uses short homologous sequences of DNA termed microhomologies to direct repair and these microhomologies are seen as single-stranded overhangs found on the ends of double-strand breaks. When the overhangs are perfectly compatible, NHEJ ligates and repair the break. When these overhangs are not compatible, imprecise repair leading to deletion of nucleotides can also occur which is much more common .
The erosion or disintegration of rocks, building materials, etc., caused by chemical reactions (chiefly with water and substances dissolved in it) rather than by mechanical processes
Answer:
The correct answer will be option-B (purine).
Explanation:
Nucleic acid structure is made up of monomer unit called nucleotide. Each nucleotide is composed of a five-carbon sugar, a phosphate group and five types of nitrogenous bases.
The nitrogenous bases are categorized in two forms the purines (adenine and guanine ) and the pyrimidines (cytosine, thymine and uracil). The "purines" contain double rings in their structure due to which they appear larger in size than pyrimidines which are made up of single rings.
Thus, Option-B is the correct answer.
