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Nematode Structure and Function (view source)
Revision as of 17:11, 8 August 2010
, 17:11, 8 August 2010no edit summary
One of the most distinctive features of some male nematodes is the presence of a copulatory bursa, seen in nematodes of the order Strongylida. Nematodes with a copulatory bursa are known as '''Bursate''', whilst those without are '''non-bursate'''. This bursa is at the posterior end of the nematode and is formed from alae with laeral rays that are used for grasping onto the body of the female during copulation.
One of the most distinctive features of some male nematodes is the presence of a copulatory bursa, seen in nematodes of the order Strongylida. Nematodes with a copulatory bursa are known as '''Bursate''', whilst those without are '''non-bursate'''. This bursa is at the posterior end of the nematode and is formed from alae with laeral rays that are used for grasping onto the body of the female during copulation.
====Females====
====Females====
[[Image:Female nematode xsection.jpg|thumb|right|200px|Cross section of a female nematode showing the position of the uterus - I. Livingsotne - BIODIDAC]]
Female nematodes usually have a single genital pore through which sperm may enter the uterus and oviduct, this pore is also referred to as a vulva and may be covered by a vulval flap. The uterus may take many forms form being short and straight, long with a single bend or a coiled form. Eggs produced in the ovaries populate the oviducts and uterus and may be released as embryonated or non embroynated eggs once fertilisation has occured. A small muscular organ exists at the vulval opening of some species known as the '''ovijector''', this organ aids in the expulsion of eggs from the vulva. Unlike in male nematodes the end of the female is usually blunt ended with the anus being positioned proximally on the body wall.
Female nematodes usually have a single genital pore through which sperm may enter the uterus and oviduct, this pore is also referred to as a vulva and may be covered by a vulval flap. The uterus may take many forms form being short and straight, long with a single bend or a coiled form. Eggs produced in the ovaries populate the oviducts and uterus and may be released as embryonated or non embroynated eggs once fertilisation has occured. A small muscular organ exists at the vulval opening of some species known as the '''ovijector''', this organ aids in the expulsion of eggs from the vulva. Unlike in male nematodes the end of the female is usually blunt ended with the anus being positioned proximally on the body wall.