NEET BIOLOGY

Detailed explanation-1: -In eukaryotes, the cell cycle consists of four discrete phases: G1, S, G2, and M. The S or synthesis phase is when DNA replication occurs, and the M or mitosis phase is when the cell actually divides.

Detailed explanation-2: -Initiation of DNA replication in eukaryotes begins with the binding of the origin recognition complex (ORC) to origins of replication during the G1 phase of the cell cycle. The ORC complex then serves as a platform for forming much more complicated pre-replicative complexes (pre-RCs).

Detailed explanation-3: -DNA replication occurs in the nucleus in eukaryotic cells and in the nucleoid region of prokaryotic cells. Eukaryotic cells are cells that have a nucleus and membrane bound organelles, such as plant cells and animal cells. Eukaryotic cells contain their DNA in the nucleus, and thus this is where DNA replication occurs.

Detailed explanation-4: -At the heart of the eukaryotic cell-division cycle are the precise duplication and segregation of chromosomal DNA. These two events take place at distinct points of the cell cycle: DNA is replicated during S phase, and then the replicated DNA strands are accurately partitioned to the two daughter cells during M phase.