Synthesis phase

Definition

The synthesis phase is a critical part of the cell cycle where DNA replication occurs, leading to the duplication of the cell's genetic material. This phase ensures that each daughter cell will have an identical set of chromosomes after cell division. During this period, not only is the DNA copied, but associated proteins and organelles may also be synthesized, setting the stage for successful cell division.

5 Must Know Facts For Your Next Test

1. The synthesis phase is denoted as the 'S' phase in the cell cycle.
2. DNA polymerase is the key enzyme involved in synthesizing new DNA strands during this phase.
3. Each chromosome duplicates to form sister chromatids that are connected at a region called the centromere.
4. The length of the synthesis phase can vary depending on the type of cell and its conditions, typically lasting several hours.
5. Errors during DNA replication can lead to mutations; therefore, repair mechanisms are crucial during this phase.

Review Questions

• How does the synthesis phase contribute to genetic stability in daughter cells?
  • The synthesis phase ensures genetic stability by accurately replicating the cell's DNA, producing two identical copies of each chromosome. This precise duplication is crucial because it guarantees that when mitosis occurs, each daughter cell will receive a complete set of chromosomes. If errors occur during this replication process, repair mechanisms work to correct them, preventing potential mutations that could affect genetic stability.
• Discuss the role of key enzymes involved in the synthesis phase and their impact on DNA replication fidelity.
  • Key enzymes such as DNA polymerase play a vital role during the synthesis phase by adding nucleotides to a growing DNA strand based on the template strand. These enzymes possess proofreading abilities that allow them to detect and correct mistakes in real-time. This action significantly enhances the fidelity of DNA replication, ensuring that the genetic information is accurately passed on to daughter cells, which is crucial for maintaining cellular function and stability.
• Evaluate how disruptions in the synthesis phase can lead to cellular consequences and potential implications for health.
  • Disruptions in the synthesis phase can result in incomplete or faulty DNA replication, leading to genetic mutations or chromosomal abnormalities. Such errors can have severe implications for cellular health; for example, they may contribute to uncontrolled cell division and tumor formation in cancer. Understanding these disruptions helps researchers develop targeted therapies and interventions that aim to correct or mitigate these cellular malfunctions, thereby improving health outcomes.

Related terms

Interphase: The phase of the cell cycle that includes G1, S, and G2 phases, during which the cell prepares for division and undergoes growth.

Mitosis: The process of nuclear division that follows interphase, resulting in two genetically identical daughter cells.

Chromatin: The material consisting of DNA and proteins found in the nucleus, which condenses to form chromosomes during cell division.