Ключевые слова: anatomy, asexual, biology, cancer, cell, cellular, chromosome, development, diagram, division, dna, education, embryo, fertilization, gamete, gametes, gametogenesis, haploid, human, illustration, infertility, life, male, man, medical, microbiology, mitosis, normal, pregnancy, process, production, replication, reproduction, reproductive, scheme, science, seminiferous, sertoli, sexual, sperm, spermatid, spermatocyte, spermatogenesis, spermatogonium, stages, stem, system, tubule, zygote,