Step 1: Understanding the Concept:
Spermatogenesis is a highly organized cell differentiation process that takes place inside the seminiferous tubules of the testes. Diploid stem cells go through systematic mitotic expansions, followed by a two-stage reduction division (meiosis) and a final structural remodeling phase to produce mature male gametes.
Step 2: Detailed Explanation:
Let's follow the development of a sperm cell from start to finish:
1. Spermatogonia (B): Immature, diploid germ cells lining the inner wall of the seminiferous tubules. They multiply via mitosis.
2. Primary Spermatocytes (E): Some spermatogonia grow and prepare for division by replicating their DNA, becoming diploid primary spermatocytes.
3. Secondary Spermatocytes (D): The primary spermatocytes undergo Meiosis I (reduction division), splitting evenly into two haploid secondary spermatocytes.
4. Spermatids (A): The secondary spermatocytes undergo Meiosis II (equational division) to form four haploid, round, non-motile spermatids.
5. Spermatozoa (C): The spermatids undergo a structural transformation process called spermiogenesis, developing tails and specialized heads to become mature, motile spermatozoa (sperm cells).
Arranging these stages in order gives: (B) $\rightarrow$ (E) $\rightarrow$ (D) $\rightarrow$ (A) $\rightarrow$ (C). This corresponds to option (A).
Step 3: Final Answer:
The correct sequence of events is (B), (E), (D), (A), (C).