Reproduction hermaphroditic

Experiments were also carried out injecting [3 -3H]xylosyl-MTA. The results indicated that the molecule has a very low turnover rate in D. verrucosa, since 96% of the recovered radioactivity after 24 h was associated with xylosyl-MTA. Accordingly, it was observed [126] that xylosyl-MTA is resistant to the enzyme MTA-phosphorylase which cleaves MTA but not the xylose analog, which therefore accumulates in the animal. Since xylosyl-MTA is mainly concentrated in the hermaphrodite gland of D. verrucosa and is very abundant in the eggmasses [103], it may play a role in the reproductive biology of D. verrucosa. 

Czech P., K. Weber, and D.R. Dietrich (2001). Effects of endocrine modulating substances on reproduction in the hermaphroditic snail Lymnaea stagnalis L. Aquatic Toxicology 53 103-114. 

Hermaphroditic An individual organism having both male and female reproductive organs also a Sower bearing both stamens and pistils. 

Tunicates possess a circulatory system with a one-chambered heart, a nervous system with ganglia, a hermaphroditic reproductive system, and an endocrine system73. They have two openings called siphons, which are protuberant in some species, less so in others74. A ciliary pump located in the incurrent siphon draws in sea water, passing it through the digestive tract, and out to the external environment via the excurrent siphon. 

In contrast to the protozoa, helminths are multicellular with complex reproductive systems and life cycles involving intermediate hosts for the development of larval stages and a definitive host for the adult form. Adults may be dioecious with separate sexes or hermaphroditic. Helminths are flatworms and flukes such as nematodes and tapeworms. They are common enteric pathogens and can be transferred by directly eating or drinking parasite eggs, which may exist in polluted meat or water. 

Flatworms may reproduce in several ways. Some divide asexually by fission, producing two identical offspring. Other species have all-female populations whose eggs develop without fertilization. However, most types of flatworms reproduce sexually. Individual flatworms are hermaphroditic, having both male and female reproductive organs. To cross-fertilize their gametes, two worms copulate, each donating sperm to the other. 

Reproductive processes of helminths are diverse. The adults are hermaphroditic (monoecious) or dioecious, requiring, in some cases, no fertilization, in others, self- or cross-fertilization in hermaphrodites or insemination of females by males. Reproduction by monoecious species is simplified since no mate finding is necessary. In those species where separated sexes exist, and in hermaphroditic species where cross-fertilization is preferred, various adaptations have increased the likelihood of worm pairing and mate finding in the host. 

Next to the internal folitary mode of propagation nature feems to have produced the hermaphrodite fyflem of reproduction, as in mofl flowers, and in fnails and dew-worms, in thefe the mafeuline and feminine organs are generally external and totally feparated from each other, and con fill of glands, which fecrete the fibrils with formative appetencies, and the molecules with formative propenfities from the fame mafs of blood. 

There are certain species that may have trouble meeting others of their same kind. Sessile animals, burrowing animals, or internal parasites may have this problan of meeting a member of the opposite sex. Hermaphrodites are individuals with both male and fanale reproductive systems. Although these individuals could potentially fertilize themselves, most must mate with another member of the same species. Because both individuals can assume both male and fanale roles, this doubles the chances of encountering someone with which to mate (Figure 6.18.5). 

Species that have difficulty encountering another of the same species will likely depend on hermaphroditism for sexual reproduction. 

We offer this section as a reminder that the angiosperms are not the only seed-plant lineage to have evolved hermaphrodite reproductive units (i.e. flowers) plant morphology textbooks routinely feature the remarkable hermaphrodite... 

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