The Cell Cycle and Mitosis (Unit Test)

The Stages of The Cell Cycle

• Interphase

  • Preparation for division

  • Interphase is the longest stage since during this is where the cell performs its normal functions and its genetic material is copied in preparation for cell division.

  • Cell grows, DNA duplicates, cell prepares to divide

• Mitosis

  • Prophase

    • First phase of mitosis

    • Long strands of DNA condense and are visible under the microscope as chromosomes

    • Nuclear membrane dissolves

  • Metaphase

    • The double stranded chromosomes line up in the middle of the cell called the equator or metaphase plate

    • Spindle fibers attach to the chromosomes

    • They must be in the line for mitosis to continue

  • Anaphase

    • The centromere splits and the sister chromatids separate.

    • The spindle fibers pull the sister chromatids to the opposite sides of the cell

    • The sister chromatids are now called “daughter chromosomes”. They are single stranded

  • Telophase

    • The daughter chromosomes stretch out, become thinner and are no longer visible

    • A nuclear membrane forms around each group of daughter chromosomes

    • The cell appears to have 2 nuclei at this stage.

• Cytokinesis

  • Creation of Two Daughter Cells

  • The cytoplasm divides producing 2 identical daughter cells

  • Different in Plant vs Animal cells:

    • Plant:

      • A new cell wall (plate) develops.

      • Starts from the middle and grows outwards.

    • Animal:

      • A furrow develops, pinching the cell into two parts

• The End Result of Mitosis

  • At the end of mitosis two daughter cells that are genetically identical to the parent cell are formed.

  • These daughter cells have the same number of chromosomes as the original cell.

  • The only difference is that the parent cell had double stranded chromosomes and the daughter cells have single stranded chromosomes.

  • This process occurs in all of the body’s somatic cells

  • Purpose - cell GROWTH and REPAIR