Biochemical Changes during Growth

Like the physical changes noted above, biochemical changes that occur during postem-bryonic development may also be described as allometric. That is, the relative proportions of the various biochemical components change as growth takes place. These changes are especially noticeable in endopterygotes during the final larval and pupal stages. At hatching, the fat content of a larva is typically low (less than 1% in the caterpillar Malacosoma, for example) and remains at about this level until the final larval stadium when fat is synthesized and stored in large quantity, reaching about 30% of the dry body weight. Though fat is the typical reserve substance in most insects, members of some species store glycogen. Again, this usually occurs in small amounts in newly hatched insects, but its proportion increases steadily through larval development, and at pupation glycogen may be a significant component of the dry weight (one-third in the honey bee). Like fat, glycogen is stored in the fat body.

In contrast, the proportions of water, protein, and nucleic acids generally decline during larval development. However, this is often not the situation in larvae that require large amounts of protein for specific purposes, for example, spinning a cocoon. In Bomybyx mori, for example, the hemolymph protein concentration increases sixfold in late larval development, and about 50% of the total protein content of a mature larva is used in cocoon formation. The great increase in concentration of hemolymph protein often can be accounted for almost entirely by synthesis, in the fat body, of a few specific proteins. In the fly Calliphora stygia, for example, the protein "calliphorin" makes up 75% (about 7 mg) of

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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