Hindgut

The hindgut is an ectodermal derivative and, as such, is lined with cuticle, though this is thinner than that of the foregut, a feature related to the absorptive function of this region. The epithelial cells that surround the cuticle are flattened except in the rectal pads (see below) where they become highly columnar and filled with mitochondria. Muscles are only weakly developed and, usually, the longitudinal strands lie outside the sheet of circular muscle.

The hindgut usually has the following regions: pylorus, ileum, and rectum. The pylorus may have a well-developed circular muscle layer (pyloric sphincter) and regulate the movement of material from midgut to hindgut. Also, the Malpighian tubules characteristically enter the gut in this region. The ileum (Figure 16.7A) is generally a narrow tube that serves to conduct undigested food to the rectum for final processing. In some insects, however, some absorption of ions and/or water may occur in this region. In a few species production and excretion of nitrogenous wastes occur in the ileum (Chapter 18, Section 2.2). In many wood-eating insects, for example, species of termites and beetles, the ileum is dilated to form a fermentation pouch housing bacteria or protozoa that digest wood particles. The products of digestion, when liberated by the microorganisms, are absorbed across the wall of the ileum. The most posterior part of the gut, the rectum, is frequently dilated. Though for the most part thin-walled, the rectum includes six to eight thick-walled rectal pads (Figure 16.7B) whose function is to absorb ions, water, and small organic molecules (Chapter 18, Section 4). As a result, the feces of terrestrial insects are expelled as a more or less dry pellet. Frequently, the pellets are ensheathed within the PM, which continues into the hindgut.

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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