Practice question

Genomic composition includes low-copy coding sequences and high-copy repetitive fractions with distinct functions. Satellite DNA comprises tandemly repeated, noncoding sequences organized as large continuous arrays at centromeres, telomeres and constitutive heterochromatin, further subdivided into microsatellite, minisatellite and macrosatellite classes based on repeat unit length. Highly reiterated and largely transcriptionally inert, it contributes to centromere function, heterochromatin formation and chromosome segregation fidelity. SNPs are single-base variants, exons are coding regions, ESTs represent transcribed tags. Noncoding reiterated organization defines satellite DNA distinction from low-copy functional sequences.