gonoduct

anatomy

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June 29, 2026

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The gonoducts are a pair of tubes in the female reproductive system that extend from openings called ostia to the cloaca. These ducts are crucial for reproduction, as they secrete substances added to eggs, transport and store eggs, and provide nutrition. In species with internal fertilization, the gonoducts also receive, transport, and store sperm. The muscular tracts are lined with secretory epithelium and are ciliated for part of their length. In some species, the caudal ends of the paired ducts may fuse. Gonoducts are absent in cyclostomes and some fishes, and a few vertebrates have only one functional gonoduct.12

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animal reproductive system
Tracts
…a pair of tubes (gonoducts) extending from anterior, funnel-like openings (ostia) to the cloaca, except as noted below. The gonoducts are specialized along their length for secretion of substances added to the eggs; for transport, storage, nutrition, and expulsion of eggs or the products of conception; and, in species…
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…a pair of tubes (gonoducts) extending from anterior, funnel-like openings (ostia) to the cloaca, except as noted below. The gonoducts are specialized along their length for secretion of substances added to the eggs; for transport, storage, nutrition, and expulsion of eggs or the products of conception; and, in species…
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mollusk
The reproductive system
…to transport the gametes (gonoducts): a pair of gonoducts, called oviducts for the female gametes and spermiducts, or vas deferens, for the male gametes, leads the egg and sperm, respectively, to the mantle cavity. Glands to secrete protective coatings around the egg may be present. In gastropods the left…
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…to transport the gametes (gonoducts): a pair of gonoducts, called oviducts for the female gametes and spermiducts, or vas deferens, for the male gametes, leads the egg and sperm, respectively, to the mantle cavity. Glands to secrete protective coatings around the egg may be present. In gastropods the left…
Read More