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 question is incomplete as it does not have the options which are:
A) n+1; n+1; n-1; n-1
B) n+1; n-1; n; n
C) n+1; n-1; n-1; n-1
D) n+1; n+1; n; n
Answer:
Option-1
Explanation:
The laws of inheritance were concluded from the result of Mendel's experiment which is based on the fact that gametes are formed. Later research suggested that gametes are formed by the process of meiosis which takes place in two phases and recombination is a characteristic of Meiosis.
If during anaphase I of meiosis I, the alleles fails to separate that is nondisjunction takes place at anaphase I, Then the resulting daughter cells will have unequal distribution of chromosomes.
One daughter cell will receive 1 extra copy of the chromosome while another daughter cell will receive 1 less chromosome therefore ploidy level will be n+1 and n-1.
During meiosis II, 2 more daughter cells will be formed with the same ploidy level therefore in last the meiosis will result in 2 (n+1) and 2 (n-1) cell.
Thus, Option-1 is the correct answer.
First of all, sex is a type of sexual reproduction. It’s meiosis. In meiosis, it has different stages and one of those stages is called Prophase 1. In prophase 1, genetic variation occurs.
Number one is sex cells are created
Light. That's the chemical equation for photosynthesis
