Question

The telomeres of eukaryotic chromosomes consist of short sequences of

• A. Cytosine rich repeats
• B. Adenine rich repeats
• C. Guanine rich repeats
• D. Thymine rich repeats

Answer 1

The correct option is C Guanine rich repeats

Telomeres are repetitive nucleotide sequences located at the termini of linear chromosomes of most eukaryotic organisms. In most eukaryotic chromosomes, telomere DNA sequences are arrays of short guanine-rich repetitive sequences that terminate in a 3 single-strand G-rich overhang (150200 nucleotides). The G-rich strand is synthesized by a telomere-specific RT, called as telomerase, using a small region of its RNA subunit as template and the 3-OH on the end of the chromosome as a primer. For vertebrates, the sequence of nucleotides in telomeres is TTAGGG. Most prokaryotes, lacking this linear arrangement, do not have telomeres. So, the telomeres of eukaryotic chromosomes consists of short sequence of guanine rich repeats and not cytosine, adenine and thymine repeats. Thus, option C is correct and other options are wrong.