In: Biology
Understand the steps of the eukaryotic cell cycle.
The phases of Cell cycle in eukaryotes consists of following steps:
1. Gap 1 (G1) phase: In this phase, cell growth occurs, increases in size and prepare for replication. It is regarded as the primary growth phase and longest phase
2. Synthetic (S) Phase: DNA replication occurs in this phase
3. Gap 2 (G2) Phase: Further cell growth and preparation for mitosis occurs in this stage. The cell organelles are replicated and microtubules are organized.
4. Mitosis (M) phase: It is the cell division phase which consists of following steps
i. Interphase:It is the period where cells spend most of their life and depicts the stage of cell before cell division. The cell grows with the help of nutrients and exerts its function according to the information present on DNA. During the middle stage of interphase, DNA replicates and in later stages cells make a copy of its centrioles by which cell becomes ready to divide
ii. Prophase: In prophase, centrioles separate and begin to form spindles while DNA condenses, coils into chromosomes. Centrioles move to the opposite sides of the nucleus and spindle fibers form a bridge between the ends of the cell while nuclear membrane starts dissolving slowly
iii. Metaphase: There is an intermediate prometaphase in which Nuclear membrane breaks down and spindles attach to the chromosome centromeres. In the metaphase, chromosome lines up at the metaplate
iv. Anaphase: With the help of the spindle fibers, centrioles pull apart chromosomes at centromeres resulting in two identical separate chromosomes. Chromosomes are pulled apart from each other and cell stretches as the opposite ends are pushed apart
v. Telophase: Nuclear membrane is reformed and chormosomes are uncoiled and the cytokinensis (division of cytoplasm),
Finally the cells completely cleave into two identical daughter cells