Male

Functions of the male reproductive system include production, storage, and, finally, delivery to the female of sperm. In some species, the system produces substances transferred during copulation that regulate female receptivity and fecundity (Gillott, 1995,2003; Wolfner, 1997, 2002). An additional function may be to supply the female with nutrients that can be incorporated into developing oocytes, thereby increasing the rate and number of eggs produced.

The male system includes paired testes (in Lepidoptera these fuse to form a single median organ), paired vasa deferentia and seminal vesicles, a median ejaculatory duct, and various accessory glands (Figure 19.4). The testes, which lie either above or below the gut, comprise a varied number of tubular follicles bound together by a connective tissue sheath. The follicles may open into the vas deferens either confluently or in a linear sequence. The wall of each follicle is a layer of epithelium set on a basal lamina. Within the follicles several zones of development can be readily distinguished (Figure 19.5). The distal zone is the germarium in which spermatogonia are produced from germ cells. In Orthoptera,

FIGURE 19.4. Examples of male reproductive systems (not to scale). (A) Melanoplus sanguinipes (Orthoptera); (B) Lytta nuttalli (Coleoptera); (C) Anagasta kuhniella (Lepidoptera); and (D) Drosophila melanogaster (Diptera). In M. sanguinipes 16 pairs of tubules make up each collateral gland (CG). There are 4 white tubules (WT), 10 short hyaline tubules (SHT), and a long hyaline tubule (LHT). The 16th tubule serves as a seminal vesicle (SV). In L. nuttalli there are three tubules in each collateral gland; a spiral tubule (SpT), short tubule (ST), and a long tubule (LT). Other abbreviations: CED, cuticular ejaculatory duct; D, duplex; EB, ejaculatory bulb; ED, ejaculatory duct; LVD, lower vas deferens; MED, mesodermal ejaculatory duct; T, testis; TF, testis follicle; UVD, upper vas deferens; VD, vas deferens. (A, from C. Gillott, 2002, Insect accessory reproductive glands: Key players in production and protection of eggs, in: Chemoecology of Insect Eggs and Egg Deposition (M. Hilker and T. Meiners, eds.). By permission of Blackwell Verlag, Berlin; B, from G. H. Gerber, N. S. Church, and J. G. Rempel, 1971, The anatomy, histology, and physiology of the reproductive systems of Lytta nuttalli Say (Coleoptera: Meloidae). I. The internal genitalia, Can. J. Zool. 49:523-533. By permission of the National Research Council of Canada; C, from a diagram supplied by Dr. J. G. Riemann; D, from E. Kubli, 1996, The Drosophila sex-peptide: A peptide pheromone involved in reproduction, Adv. Dev. Biochem. 4:99-128. By Permission of JAI Press, Inc.)

FIGURE 19.4. Examples of male reproductive systems (not to scale). (A) Melanoplus sanguinipes (Orthoptera); (B) Lytta nuttalli (Coleoptera); (C) Anagasta kuhniella (Lepidoptera); and (D) Drosophila melanogaster (Diptera). In M. sanguinipes 16 pairs of tubules make up each collateral gland (CG). There are 4 white tubules (WT), 10 short hyaline tubules (SHT), and a long hyaline tubule (LHT). The 16th tubule serves as a seminal vesicle (SV). In L. nuttalli there are three tubules in each collateral gland; a spiral tubule (SpT), short tubule (ST), and a long tubule (LT). Other abbreviations: CED, cuticular ejaculatory duct; D, duplex; EB, ejaculatory bulb; ED, ejaculatory duct; LVD, lower vas deferens; MED, mesodermal ejaculatory duct; T, testis; TF, testis follicle; UVD, upper vas deferens; VD, vas deferens. (A, from C. Gillott, 2002, Insect accessory reproductive glands: Key players in production and protection of eggs, in: Chemoecology of Insect Eggs and Egg Deposition (M. Hilker and T. Meiners, eds.). By permission of Blackwell Verlag, Berlin; B, from G. H. Gerber, N. S. Church, and J. G. Rempel, 1971, The anatomy, histology, and physiology of the reproductive systems of Lytta nuttalli Say (Coleoptera: Meloidae). I. The internal genitalia, Can. J. Zool. 49:523-533. By permission of the National Research Council of Canada; C, from a diagram supplied by Dr. J. G. Riemann; D, from E. Kubli, 1996, The Drosophila sex-peptide: A peptide pheromone involved in reproduction, Adv. Dev. Biochem. 4:99-128. By Permission of JAI Press, Inc.)

FIGURE 19.5. (A) Section through testis to show arrangement of follicles; and (B) zones of maturation in testis follicle. [A, from R. E. Snodgrass, Principles of Insect Morphology. Copyright 1935 by McGraw-Hill, Inc. Used with permission of McGraw-Hill Book Company. B, after V. B. Wigglesworth, 1965, The Principles of Insect Physiology, 6th ed., Methuen and Co. By permission of the author.]

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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