Suppose a mutation affects an enzyme that is required to repair the damage to DNA caused by the loss of purine bases. This mutation causes the accumulation of about 5000 mutations in the DNA of each of your cells per day. As the average difference in DNA sequence between humans and chimpanzees is about 1%, how long will it take for humans to turn into chimpanzees

Answer: There's no way one species can become another through depuranization, which is a random change.

Explanation:

In cells, environmental (chemical or physical) and metabolic factors can cause DNA damage, which is the molecule that stores genetic material. In these cases, the damage done to the DNA is repaired.

Many of these lesions cause a permanent structural damage to the DNA, which can alter the ability to be transcribed, or can cause mutated genes to be transcribed resulting in another protein. Particularly, depurination is the hydrolytically cleavage of the β-N-glycosidic bond between the purines (adenosine or guanosine) and the carbon of the sugar group found in the DNA. This mutation results in the loss of the purine base and leads to the formation of apurinic site and results and severely disrupts the DNA structure. The most important causes of depurination is the presence of endogenous metabolites inside the cell as a result of various chemical reactions and due to the presence of mutagenic compounds. However, these apurinic sites are usually repaired by portions of the base excision repair (BER) pathway.

There's no way one species can become another through depuranization, which is a random change. Because it is highly unlikely that 5000 mutations are able to accumulate every day without being repaired, and that they are just the right mutations to have the same characteristics as a chimpanzee. If the depurinations are not repaired, the cell will most likely either die or become cancerous.