Significance of Mitosis MCQ - Practice Questions with Answers

Significance and Types of Mitosis

Significance of Mitosis:

• Mitosis results in the development of multicellular organisms, as they begin their life in the form of a unicellular zygote. It undergoes divisions to form a multicellular embryo that gives rise to a whole organism.
• In multicellular organisms, mitosis helps in growth and repair.
• In unicellular organisms, mitosis results in cell division.
• Mitosis is essential to maintain the nucleocytoplasmic ratio.

Types of Mitosis:

• In higher plants, centrioles are absent and no asters are formed. Mitosis without asters is known as anastral mitosis.
• In animals, the asters are present and mitosis is described as amphiastral or astral mitosis.
• In Intranuclear or Promitosis the nuclear membrane is not lost and spindle is formed inside the nuclear membrane e.g. Protozoans (Amoeba) and yeast. It is so because centrioles are present within the nucleus.
• In Eumitosis the  nuclear membrane is lost and spindle is formed outside nuclear membrane e.g. in plants and animals.
• In Endomitosis the Chromosomes and their DNA duplicate but fail to separate which lead to polyploidy e.g. in liver of man, both diploid (2N) and polyploid cells (4N) have been reported. It is also called endoreduplication and endopolyploidy.