Why do prokaryotes not have an issue with telomere shortening?

Why do prokaryotes not have an issue with telomere shortening?

• A. Their DNA is circular and lacks telomeres
• B. They do not replicate
• C. They have larger telomeres
• D. They use telomerase all the time

Answer: (A)

The main idea is that the end-replication problem only arises with linear chromosomes. Prokaryotes usually have a single circular chromosome, so there are no ends to shorten during replication. When the circular DNA is copied, the process yields two complete circles rather than chromosome ends losing bases, so telomeres aren’t needed and telomere shortening isn’t an issue. While eukaryotes face a gradual loss of DNA from chromosome ends, prokaryotes don’t experience that problem because their genome is circular. In short, lacking telomeres to begin with and having no ends to protect means telomere shortening isn’t a concern for prokaryotes.

The main idea is that the end-replication problem only arises with linear chromosomes. Prokaryotes usually have a single circular chromosome, so there are no ends to shorten during replication. When the circular DNA is copied, the process yields two complete circles rather than chromosome ends losing bases, so telomeres aren’t needed and telomere shortening isn’t an issue. While eukaryotes face a gradual loss of DNA from chromosome ends, prokaryotes don’t experience that problem because their genome is circular. In short, lacking telomeres to begin with and having no ends to protect means telomere shortening isn’t a concern for prokaryotes.