Cell Cycle
The cell cycle is a series of events that occur in a cell's life, leading to its growth, replication, and division into two daughter cells. It is a highly regulated and sequential process crucial for the maintenance, growth, and reproduction of multicellular organisms. The cell cycle consists of distinct phases, each serving specific functions.
-
Interphase:
- G1 Phase: The cell grows and carries out its normal functions.
- S Phase: DNA synthesis occurs, resulting in the replication of genetic material.
- G2 Phase: Continued growth and preparation for cell division.
-
Mitosis (M Phase):
- Prophase: Chromosomes condense, and the nuclear envelope breaks down.
- Metaphase: Chromosomes align at the metaphase plate.
- Anaphase: Sister chromatids separate and move towards opposite poles.
- Telophase: Chromatids arrive at poles, and new nuclear envelopes form.
-
Cytokinesis:
- The division of the cell's cytoplasm and organelles to produce two daughter cells.
- In animal cells, a cleavage furrow forms.
- In plant cells, a cell plate develops into a new cell wall.
Cell Division
Cell division is the process by which a parent cell divides into two or more daughter cells. There are two main types of cell division:
-
Mitosis:
- Results in the production of two genetically identical daughter cells.
- Essential for growth, tissue repair, and asexual reproduction.
- Maintains the chromosome number (diploid) in daughter cells.
-
Meiosis:
- Occurs in specialized cells for the formation of gametes (sperm and egg cells).
- Involves two sequential divisions, resulting in four non-identical haploid cells.
- Introduces genetic diversity through processes such as crossing over.