Advanced Placement (AP) Biology Practice Exam

What is the primary purpose of meiosis in cellular biology?

1. To produce diploid cells

2. To produce haploid gametes

3. To create somatic cells

4. To generate sister chromatids

The correct answer is: To produce haploid gametes

Meiosis is a specialized form of cell division that plays a critical role in sexual reproduction by producing haploid gametes. The primary purpose of this process is to reduce the chromosome number by half, leading to the formation of gametes, which are necessary for fertilization. In humans and many other organisms, these gametes are sperm and eggs, each containing one set of chromosomes (haploid). During meiosis, two successive divisions occur—meiosis I and meiosis II—resulting in four genetically diverse non-identical cells, each with half the original chromosome number. This reduction is essential because when two haploid gametes combine during fertilization, they restore the diploid state in the zygote, ensuring a stable chromosome number across generations. The other options do not accurately represent the focus of meiosis: diploid cells are produced through mitosis, somatic cells are also generated through mitosis rather than meiosis, and sister chromatids are formed during the S phase of the cell cycle, prior to the division processes of meiosis. Hence, the accurate reflection of meiosis’s role is its function in generating haploid gametes.