Cell Cycle and Mitosis Overview

Cell Cycle and Mitosis Overview

• Mitosis is a vital process for growth and development, allowing cells to divide and form new cells.
• In a single cell cycle, two daughter cells are produced from one parent cell.

Phases of the Cell Cycle

• Interphase:
  • Longest phase where the cell grows, matures, and duplicates its DNA.
• Mitosis:
  • Comprised of four key phases:
    • Prophase:
      • Chromatin condenses into chromosomes and the nuclear membrane dissolves.
    • Metaphase:
      • Chromosomes align at the cell's equator.
    • Anaphase:
      • Chromatids are pulled apart to opposite ends of the cell.
    • Telophase:
      • Nuclear membranes form around each set of chromatids and the cell membrane begins to pinch in to divide the cytoplasm.
• Cytokinesis:
  • Begins during telophase, resulting in the physical separation of the cell into two daughter cells.

Cellular Components and Functions

• Spindle:
  • Structure responsible for moving chromatids during mitosis.
• Centrioles:
  • Anchor points for the spindle fibers during cell division.
• Centromere:
  • Holds individual chromatids together prior to separation.

Chromosome Count

• Human cells typically have 46 chromosomes; each daughter cell will also have 46 chromosomes after mitosis.
• A dog's cell, which has 72 chromosomes, will produce two daughter cells with 72 chromosomes each.

Cell Cycle Checkpoints and Phases

• G1 Phase:
  • The cell increases in size and prepares for DNA synthesis.
• S Phase:
  • DNA duplication occurs, ensuring that each daughter cell receives an exact copy of the genetic material.
• G2 Phase:
  • The cell prepares for mitosis and checks that the DNA has been accurately replicated.
• Checkpoint:
  • Ensures that genetic material is copied correctly before proceeding to division.

Reproductive Strategies

• Asexual Reproduction:
  • Involves one parent producing offspring, resulting in clones that are genetically identical to the parent.
• Sexual Reproduction:
  • Involves two parents (male and female), producing unique offspring through the fusion of sperm and egg cells.