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Male accessory glands in humans are the seminal vesicles, prostate gland, and the bulbourethral glands. In insects, male accessory glands produce products that mix with the sperm to protect and preserve them. Some insecticides can induce an increase in the protein content of the male accessory glands of certain types of insects. This has the unintended effect of increasing the number of offspring they produce.〔Li-Ping Wang, Jun Shen, Lin-Quan Ge, Jin-Cai Wu, Guo-Qin Yang and Gary C. Jahn. (Insecticide-induced increase in the protein content of male accessory glands and its effect on the fecundity of females in the brown planthopper ''Nilaparvata lugens'' Stål (Hemiptera: Delphacidae) ). Crop Protection 29:1280-1285.〕 These glands secrete fluid for nourishment of sperms. ==Accessory Glands== The male accessory glands are the ampullary, vesicular, prostate, bulbourethral, and urethral glands. The products of these glands serve to nourish and activate the spermatozoa, to clear the urethral tract prior to ejaculation, serve as the vehicle of transport of the spermatozoa in the female tract, and to plug the female tract after placement of spermatozoa to help ensure fertilization. Although the glands are usually described as being branched tubular or branched tubuloalveolar, they vary in their organization and in their distribution in different species. Ampullary Glands Each of these branched tubular glands lined by simple columnar epithelium is an enlargement of the ductus deferens in its terminal portion. These are typical tubular glands in ruminants, horses and dogs; absent in the cat and poorly developed in boars. The function of the white serous secretion is not known. Vesicular Glands The secretory endpieces of these glands are lined with simple columnar epithelium; the main ducts are lined with stratified columnar epithelium. These glands do not occur in carnivores, but are present in some form in horses, ruminants and swine. Seminal fluid, the product of this gland, serves as a vehicle for the transport of spermatozoa. Prostate Gland Grossly the prostate gland can be divided into two parts: the body and the disseminate part. Low cuboidal to low columnar epithelium provides the lining for this compound, tubuloalveolar gland which consists primarily of serous secretory end pieces. The secretion of this gland is more serous in dogs and more mucous in bulls. It serves to promote the movement of spermatozoa and to form a vaginal plug. Additionally, in bulls, the secretion contains high amounts of fructose and citric acid. Concretions may be present in the secretory end pieces as well as parts of the duct system. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Male accessory gland」の詳細全文を読む スポンサード リンク
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