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Earthworms have many internal parasites, including protozoa, platyhelminthes, mites, and nematodes; they can be found in the worms' blood, seminal vesicles, coelom, or intestine, or in their cocoons (e.g. the mite Histiostoma murchiei is a parasite of earthworm cocoons [53]).
The two worms exchange sperm. Both worms then secrete cocoons, which contain several eggs each. These cocoons are lemon-shaped and are pale yellow at first, becoming more brownish as the worms inside become mature. These cocoons are clearly visible to the naked eye. At 25°C, E. fetida hatches from its cocoon in about 3 weeks. [17]
When the worms mature into the L4 stage, they rupture the capillaries and are released into the alveoli, where they are coughed up and swallowed. They then reach the small intestines 3–4 days after the initial infection. The worms become adults after the final molt into the L5 stage, where they begin laying eggs on day 6 of infection. [1]
The available data on mebendazole, albendazole, and pyrantel pamoate use in pregnancy is limited and they are all assigned to pregnancy category level C. Treatment of a pinworm infection during pregnancy is only recommended for patients with significant symptoms that may be causing adverse effects to the pregnant woman such as loss of sleep and ...
Earthworms are another example of a simultaneous hermaphrodite. Although they possess ovaries and testes, they have a protective mechanism against self-fertilization. Sexual reproduction occurs when two worms meet and exchange gametes, copulating on damp nights during warm seasons.
Worms commonly live for about one year, [5] during which time females can lay up to 20,000 eggs per day. Recent studies using genome-wide scanning revealed that two quantitative trait loci on chromosome 9 and chromosome 18 may be responsible for a genetic predisposition or susceptibility to infection of T. trichiura by some individuals.
Over the next two to three months the larvae develop into adult male and female worms. The male remains small at 4 cm (1.6 in) long and 0.4 mm (0.016 in) wide; the female is comparatively large, often over 100 cm (39 in) long and 1.5 mm (0.059 in) wide. [5] Once the worms reach their adult size they mate, and the male dies. [6]
The asexual, all-female whiptail species Aspidoscelis neomexicanus (center), which reproduces via parthenogenesis, is shown flanked by two sexual species having males, A. inornatus (left) and A. tigris (right), which naturally hybridized to form A. neomexicanus.