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Parthenogenesis When development of organism takes place without fertilization, the process is called as parthenogenesis. Parthenogenesis is of two types viz. 1.       Natural 2.       Artificial Natural parthenogenesis: ·          Eggs that develop without fertilization naturally, the process is called as natural parthenogenesis. ·          It is commonly seen in Aphids, Phyllopods and Rotifers at sometimes of the years not always ·          Whereas in case of bees and wasps males are always produced from unfertilized egg. Thus, males are always haploid and females are diploid because females are produced from fertilized egg. ·          In some species such as Tenthredinidae, reproduction is alays parthenogenetically and males of this species are not known. Artificial parthenogenesis: ·          In normal conditions some eggs do not develop unless they are fertilized. ·          In such conditions, when ripe egg is induced artificially the development start
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Gametogenesis The process of formation of gametes is called as gametogenesis. It is basically of two types viz a)       Spermatogenesis b)       Oogenesis Spermatogenesis: -           The process of formation of sperms i.e. male gametes is called as spermatogenesis. -           It occurs in male gonads i.e. 1 O sex organ; testis. -           Development and maturation of sperms takes place in seminiferous tubules inside testis. -           Seminiferous tubules are lined by germinal epithelium which gives rise to germ cells i.e. gametes; sperms. -           Germinal epithelium cells divide and re-divide to give rise to large number of cells called as Spermatogonia or Sperm Mother Cell (SPM) -           There are three phases in spermatogenesis viz. 1.       Phase of multiplication 2.       Phase of growth 3.       Phase of maturation 1.       Phase of multiplication: -           During this phase, germ cells undergo repeated mitotic div
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