Embryonic Development

cell surfaces within the embryo. Thus, a scaffold of axonal pathways is initially erected, 611

which later-developing axons are then able to follow, being guided by specific recognition signals on the surfaces of the pioneer neurons (Goodman, 1984; Goodman and Bastiani, 1984). Peripheral pioneer neurons, originating from ectoderm at the tips of appendages, have also been identified. These grow toward the central nervous system, serving later as guides for motor axons innervating effectors, especially muscles, and the sensory axons from integumental sensilla. The peripheral pioneer axons die when the necessary connections have been established (Heming, 2003).

As embryogenesis continues, fusion of ganglia occurs in the head region to form the brain and subesophageal ganglion and at the posterior end of the abdomen where ganglia from segments 8-11 form a composite structure. In embryos of species belonging to different orders of Insecta, varying degrees of fusion of other ganglia may subsequently occur.

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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