Female

CHAPTER 19 Functions of the female reproductive system include production of eggs, including yolk and chorion formation, reception and storage of sperm, sometimes for a considerable period, and coordination of events that lead to fertilization and oviposition.

Though details vary, the female system (Figure 19.1) essentially includes a pair of ovaries from each of which runs a lateral oviduct. The lateral oviducts fuse in the midline, and the common oviduct typically enters a saclike structure, the vagina. In some species the vaginal wall evaginates to form a pouchlike structure, the bursa copulatrix, in which

FIGURE 19.1. Representative female reproductive systems (not to scale). (A) Melanoplus sanguinipes (Orthoptera); (B) Rhodnius prolixus (Hemiptera); (C) Periplaneta americana (Dictyoptera); and (D) Nasonia vitripennis (Hymenoptera). Abbreviations: BC, bursa copulatrix; CA, calyx; CG, collateral (accessory) glands; CO, common oviduct; DG, Dufour's gland; LCG, left colleterial gland; LO, lateral oviduct; OV, ovariole; PCG, pseudocolleterial gland; RCG, right colleterial gland; SP, spermatheca; SPG, spermathecal gland; VG, venom gland; VGR, venom gland reservoir. [A, C, D, 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 R. P. Ruegg, 1981, Factors influencing reproduction in Rhodnius prolixus (Insecta: Hemiptera), Ph.D. Thesis, York University, Canada.]

FIGURE 19.1. Representative female reproductive systems (not to scale). (A) Melanoplus sanguinipes (Orthoptera); (B) Rhodnius prolixus (Hemiptera); (C) Periplaneta americana (Dictyoptera); and (D) Nasonia vitripennis (Hymenoptera). Abbreviations: BC, bursa copulatrix; CA, calyx; CG, collateral (accessory) glands; CO, common oviduct; DG, Dufour's gland; LCG, left colleterial gland; LO, lateral oviduct; OV, ovariole; PCG, pseudocolleterial gland; RCG, right colleterial gland; SP, spermatheca; SPG, spermathecal gland; VG, venom gland; VGR, venom gland reservoir. [A, C, D, 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 R. P. Ruegg, 1981, Factors influencing reproduction in Rhodnius prolixus (Insecta: Hemiptera), Ph.D. Thesis, York University, Canada.]

spermatophores and/or seminal fluid is deposited during copulation. Also connected with the 563

vagina are the spermatheca in which sperm are stored and various accessory glands. In some

RE^PR^^ DUCTION

species part of the spermatheca takes the form of a diverticulum, the spermathecal gland. It is noteworthy that the ovaries themselves lack innervation though the ductal components of the system receive nerves from the terminal abdominal ganglion (Sections 5 and 7.2).

The ovaries are usually dorsolateral to the gut, and each comprises a number of tubular ovarioles ensheathed by a network of connective tissue in which numerous tracheoles and muscles are embedded. The number of ovarioles per ovary, though approximately constant within a species, varies widely among species. For example, in some viviparous aphids and in dung beetles there is one ovariole per ovary in contrast to the more than 2000 ovarioles per ovary in some higher termite queens. The wall of each ovariole includes an outer epithelial sheath and an inner acellular, elastic layer, the tunica propria. Each ovariole (Figure 19.2)

terminal terminal

PANOISTIC POLYTROPHIC

FIGURE 19.2. Types of ovarioles. The upper portion of each figure is enlarged to a greater extent than the lower in order to make details of germarial structure clear. [After A. P. Mahowald, 1972, Oogenesis, in: Developmental Systems: Insects, Vol. I (S. J. Counce and C. H. Waddington, eds). By permission of Academic Press Ltd., and the author.]

PANOISTIC POLYTROPHIC

FIGURE 19.2. Types of ovarioles. The upper portion of each figure is enlarged to a greater extent than the lower in order to make details of germarial structure clear. [After A. P. Mahowald, 1972, Oogenesis, in: Developmental Systems: Insects, Vol. I (S. J. Counce and C. H. Waddington, eds). By permission of Academic Press Ltd., and 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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