question_answer 23)

  With regard to mature mRNA in eukaryotes (a) exons and introns do not appear in the mature RNA (b) exons appear but introns do not appear in the mature RNA (c) introns appear but exons do not appear in the mature RNA (d) both exons and introns appear in the mature RNA

Answer:

                  (b) In eukaryotes, the monocistronic structural genes have interrupted coding sequences i.e., the genes in eukaryotes are split. The coding sequences or expressed sequences are defined as exons. These sequences (exons) appear in mature or processed RNA, The exons are interrupted by introns or intervening sequences which do not appear in mature or processed RNA.