What is a primary purpose of mitosis in multicellular organisms?

• A. Producing gametes.
• B. Growth and tissue repair.
• C. Reducing chromosome number.
• D. Increasing genetic variation.

Answer: (B)

Mitosis is about making new somatic cells with the same number of chromosomes so the organism can grow and replace damaged tissues. In multicellular beings, growth requires increasing cell numbers, and tissue repair depends on dividing cells that are genetically identical to the originals. By preserving the chromosome number and producing nearly identical daughter cells, mitosis supports development and maintenance of the organism.

Producing gametes, reducing chromosome number, and increasing genetic variation are processes tied to meiosis and sexual reproduction, not mitosis. Meiosis halves the chromosome count to form gametes, and the combination of gametes during fertilization introduces genetic variation through recombination and assortment.