Science 13.1

• Two distinct kinds of cell division take place in our body: Mitosis and Meiosis
• Mitosis takes place in our body fells called somatic cells.
• Mitosis is responsible for the increase in weight and height.
• Meiosis takes place in the ovaries and testes of animals, including humans.
• Meiosis is responsible for the formation of gametes or sex cells.
• New cells are formed through cell division, which was discovered by Rudolf Virchow, a German pathologist in 1858.
• The process of cell division is repeated over and over in a process called the cell cycle.
• The cell cycle is divided into to groups: Interphase and Mitotic or M-phase
• Interphase is describes as the resting stage.
• During G1 or the first gap, the cell undergoes physical growth.
• S subphase is the synthesis phase.
• G2 or second gap, the replicated chromosomes condense.
• Mitosis or M phase is divided into different stages:

  Prophase, Metaphase, Anaphase, and Telophase.
• Prophase, the nuclear membrane, and nucleolus begin to break down.
• Metaphase

  The double-stranded chromosomes align themselves at the equator of the cell.
• In Anaphase, forces originating from the poles pull the chromatids.
• Telophase is the final stage of mitosis