In mitotic cell division, how many genetically identical daughter cells are produced from a single parent cell?

Introduction / Context:
Mitosis is the type of cell division that allows organisms to grow, repair damaged tissues, and in some species reproduce asexually. A very common exam question checks whether students remember how many daughter cells are formed from one mitotic division and what happens to the chromosome number during this process. This question focuses on the basic outcome of mitosis in terms of the number of daughter cells produced from a single parent cell.

Given Data / Assumptions:

• We are dealing with mitosis, not meiosis.
• There is one parent cell entering mitotic division.
• The parent cell is assumed to be diploid, although the principle applies to haploid cells as well.
• The question asks for the number of daughter cells formed after one complete mitotic division.

Concept / Approach:
Mitosis is often described as an equational division because the chromosome number of the daughter cells remains the same as that of the parent cell. The cell cycle consists of interphase (with DNA replication) followed by the mitotic phase, which includes prophase, metaphase, anaphase, and telophase, and then cytokinesis. After DNA replication, the cell has duplicated chromosomes, but it is still a single cell. During mitosis and cytokinesis, the cell divides its nucleus and cytoplasm so that two separate cells are formed, each getting one complete set of chromosomes. Therefore, one parent cell produces exactly two daughter cells in mitosis.

Step-by-Step Solution:
Step 1: The parent cell enters interphase and duplicates its DNA, so each chromosome now consists of two sister chromatids. Step 2: During prophase and metaphase, the chromosomes condense and line up at the cell equator. Step 3: In anaphase, sister chromatids separate and move to opposite poles of the cell. Step 4: During telophase, nuclear envelopes reform around each set of chromosomes at the two poles. Step 5: Cytokinesis then divides the cytoplasm into two parts, physically separating the cell into two daughter cells. Step 6: Each daughter cell receives an identical set of chromosomes and is genetically similar to the parent cell.

Verification / Alternative check:
Standard biology textbooks describe mitosis as a process that produces two daughter cells with the same chromosome number as the parent. Diagrams of the cell cycle show a single cell entering mitosis and two cells at the end of cytokinesis. In contrast, meiosis produces four haploid cells after two successive divisions. This difference in the number of daughter cells is repeatedly used in exam comparisons between mitosis and meiosis, confirming that mitosis produces two daughter cells.

Why Other Options Are Wrong:
1: A single cell is the starting point, not the outcome of mitosis. 4: Four daughter cells are produced in meiosis, not in a single mitotic division. 8 and 16: These numbers would require multiple consecutive rounds of division, not just one mitotic event.

Common Pitfalls:
Students sometimes confuse mitosis with meiosis and may incorrectly choose four because meiosis produces four cells. Others may think about repeated cell cycles and forget that the question is about just one division. A simple way to remember is that mitosis equals two genetically identical daughter cells, while meiosis equals four genetically different haploid cells.

Final Answer:
The correct answer is 2.