Postembryonic Development

Apart from permitting the expression of adult characters, the low concentration of JH during the final stadium has another major effect: it leads to degeneration of the molt glands, which disappear within a few days of eclosion in most insects, exceptions being apterygotes, which, as noted earlier, continue to grow and molt as adults and solitary locusts whose corpora allata apparently do not become completely inactive at the final molt. Though degeneration of the molt glands is of critical importance in the life history of an insect, when viewed in the perspective of metamorphosis the phenomenon becomes simply an example of apoptosis (programmed cell death). In other words, the molt glands, like many other structures in juvenile insects, especially endopterygotes, are larval tissues whose structural well-being is dependent on JH. In the absence of JH, at metamorphosis, they histolyze. It remains unclear how JH affects the molt glands. However, a very early sign of apoptosis in the glands is nuclear DNA cleavage; this is prevented by the experimental application of JH (Dai and Gilbert, 1998).

The precise modes of action of the developmental hormones remain unclear. One of the earliest observable effects of PTTH is renewed RNA synthesis in the molt glands. This

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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