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 Insect Morphology and SystematicsInsect Morphology and Systematics 16248680811470158, Chin sevish Abdurauf Fitrat - 11.03.2016 16-14-20, 5 sinf 1-Mavzu Biologiya hayot haqidagi fan, 1-mavzu. Hasharotlar ekologiyasi fani rivojlanish tarixiTYPES OF REPRODUCTION
1. OVIPARITY
Majority of female insects are oviparous that is, they lay eggs. Embryonic development occurs
after oviposition by utilizing the yolk, e.g. Head louse moths.
2. VIVIPARITY
Unlike oviparous, here initiation of egg development take place within the mother. The life cycle is
shortened by retention of eggs and even developing young within the mother. Four main types of
viviparity are observed in different insect groups.
i. OVOVIVIPARITY
Fertilized eggs containing yolk are incubated inside the reproductive tract of the female and
hatching of egg occur just prior to or soon after oviposition e.g. Thysanoptera, some cockroaches,
few beetles, and some flies-(fleshfly). Fecundity of this group is low.
ii. PESEUDOPLACENTAL VIVIPARITY
This occurs when a yolk-deficient egg develops in the genital tract of the female. The mother
provides a special placenta-like tissue, through which nutrients are transferred to developing
embryos. There is no oral feeding and larvae are laid upon hatching. e.g. aphids, some earwigs,
psocids and polytenid bugs.
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