Respuesta :

Answer: Tightly wound chromosomes, composed of DNA, must unwind before replication. Cell replication splits a cell into two parts, both of which become new, fully functioning cells. Before this can happen, however, cells require a full complement of DNA for each of the new daughter cells that will form as a result of the split. Because of this, DNA makes a copy of itself in a process known as replication during interphase, a stage that occurs before cells divide.

Cell Phases: Mitosis is the process by which parent cells each divide into two identical daughter cells. However, this majority of the cell's time is spent in interphase, during which it performs normal metabolic functions necessary for the organism, such as manufacturing protein. DNA occurs during the S phase of interphase, sandwiched between the G1 and G2 phases. The cell uses checkpoint signals to ensure at the end of G1 that it is big enough to replicate and at the end of G2 to determine whether or not DNA replication has succeeded. If so, the cell can undergo mitosis, at which point DNA winds up tightly for easy transport during the process.

DNA Replication: Replication begins with DNA unwinding and unzipping, its two strands coming apart. While only one side is the “correct” code, containing the actual genetic information used to build the organism’s proteins, both can be the base for a new strand of complete DNA. The enzyme DNA polymerase matches up each base with the correlating base: adenine with thymine and guanine with cytosine. When each pre-existing base has been matched to a nucleotide, which also contains the sugar and phosphate of the DNA’s backbone, the strand is complete.

DNA copies itself during the - S phase (Synthesis phase) of Interphase.

Interphase is the metabolic phase of the cell cycle, in which the cell gets nutrients and metabolizes them, grows, replicates its DNA in preparation for mitosis, and conducts other "normal" cell functions.

  • Cells undergo the Interphase before Mitosis occurs (M phase).
  • DNA replication occurs during the S phase (the Synthesis phase) of the cell cycle
  • The base-pairing rules are crucial for the process of replication.
  • DNA replication occurs when DNA is copied to form an identical molecule of DNA

Thus, DNA copies itself during the - S phase (Synthesis phase) of Interphase.

Learn more:

https://brainly.com/question/21064480