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Human Reproduction — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction4 Marks
Question
Explain spermatogenesis.
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Answer

Spermatogenesis : The process of formatio and maturation of sperms by mitosis and meiosis from germinal epithelium cells in the testis is called spermatogenesis.
Process of Spermatogenesis : Spermatogonia present in the inner layer of seminiferous tubules increase in number by mitosis. Each spermatogonia is diploid, that is, the number of chromosome is 46. Now meiosis division occurs in spermatogonia, which result in the formation of primary spermatocytes. A primary sperm cell completes the first meiosis to form two identical haploid cells, which are called spermatocytes. Each cell thus formed has 23 chromosomes.Secondary spermatids undergo second meiosis to form four equal haploid spermatids (see figure). These spermatids finally get transformed into sperms. The process of transformation of spermatids into sperms is called spermatogenesis.
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