Why are telomeres a necessary component of linear chromosomes?

Bacause they protect the chromosomes

Explanation:

A telomere is a repetitive region located at the ends of a chromosome, their function is to act as caps to protect the inner regions when the chromosome is worn down during DNA replication. This worning out happens because a short stretch of DNA is not covered by an Okazaki fragment and therefore is not copied, eventually over multiple rounds of division the telomers will prevent the shortening to reach the important inner part that contains the genetical information.

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