"SCIENTIFIC" is the answer to this question,
hugs :))
Answer:
Repair mechanism for base cleavage (BER)
Explanation:
Repair by base cleavage (BER)
The altered bases are specifically recognized by glycosylases and removed, generating an AP site. The hole is filled by a DNA polymerase that takes the healthy strand as a template. This system arises not only by exposure to external agents, but also by the cell's own activity.
In case of damage in more than one nucleotide, repair by nucleotide excision (NER) is performed.
Nucleotide excision repair (NER)
The damaged area is recognized by UvrA and B, then A and B separate and UvrC enters which forms a complex with endonuclease activity with B. This enzyme cuts the T-dimer and the gap is filled by a DNA polymerase. There is also the TC-NER system (transcription-coupled nucleotide repair system). The alteration of these mechanisms gives rise to diseases such as: Xeroderma pigmentosum, Trichotiodystrophy or Cockayne Syndrome
The answer is a hair root.
Nuclear DNA is commonly extracted from the hair root. The hair root consists of keratinocytes. Keratinocytes are cells found in the epidermis. As all other cells, they contain DNA material. When keratynocites die, they get converted into keratoid material in the process of cornification. As a consequence, d<span>ead cells do not contain DNA material. Therefore, the hair root is the best source of nuclear DNA than shed or cut hair when working with hair sample.</span>
