Cell division that involves the growth, development, repairs and replacement of worn out tissues is

Step 1: Analyze the question The question asks for the type of cell division responsible for growth, development, repair, and replacement of worn-out tissues.

Step 2: Explain the concept There are two main types of cell division:

• Mitosis: One parent cell divides into two genetically identical daughter cells, each with the same chromosome number (diploid, 2n). It occurs in body (somatic) cells.
• Meiosis: One parent cell divides into four genetically different daughter cells, each with half the chromosome number (haploid, n). It occurs only in reproductive organs to form gametes (sperm and egg cells).

Step 3: Solve step by step

• A. Biosynthesis: This is the production of complex molecules in living cells. It is not a type of cell division. ❌
• B. Mitosis: This produces identical cells for growth, development, repair of damaged tissues, and replacement of worn-out cells (e.g. skin cells, blood cells). ✅
• C. Meiosis: This produces gametes for sexual reproduction and is not involved in growth or repair. ❌
• D. Synthesis: This is a general term for building up substances, not cell division. ❌

Step 4: Answer The correct answer is B. Mitosis.

Step 5: Exam tip Remember: Mitosis = Maintenance (growth, repair, replacement), while Meiosis = Gametes (reproduction). Also, mitosis gives 2 identical cells, while meiosis gives 4 different cells with half the chromosomes.