Final answer:
In DNA replication, the lagging strand is synthesized in discontinuous segments called Okazaki fragments, opposite to the continuous synthesis of the leading strand. Transcription creates mRNA utilizing a DNA template, with termination often involving a hairpin loop structure. Telomerase helps to extend the end of the chromosome, preventing DNA shortening during replication.
Step-by-step explanation:
The synthesis of DNA against the opposite template strand, known as the lagging strand, occurs in short stretches of DNA called Okazaki fragments. This is due to the antiparallel nature of DNA strands and the enzyme DNA polymerase's ability to only add nucleotides in a 5' to 3' direction. Consequently, replication of the lagging strand is discontinuous and occurs away from the replication fork, whereas the leading strand is synthesized continuously towards the replication fork.
In terms of RNA synthesis during transcription, the mRNA product is synthesized from the DNA template strand. Transcription relies on the partial unwinding of the DNA helix to form a transcription bubble. The mRNA is almost identical to the coding strand barring the replacement of T nucleotides with U nucleotides in RNA. Termination of transcription can occur via a rho-independent mechanism, characterized by a stable hairpin structure formed by C-G rich sequences, causing the polymerase to stall and release the new mRNA transcript.
The addition of DNA nucleotides at the very end of the chromosome is facilitated by the enzyme telomerase, ensuring that the DNA strands do not become progressively shorter with each cell division.