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Nematode Structure and Function (view source)

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Males are either monorchic (most secernentea) or diorchic (most Adenophera), with regards to the number of testis present. The testis are tubular structures lined with epithelium and glandular tissue, sperm are produced at the end and mature as they migrate towards the shared opening of the cloaca. Many males have paired chitinous protrusion from the cloaca known as '''spicules''', these are used for attaching to a female during copulation. The spicules are easily seen under a microscope due to their chitinous structure and their position and shape may be used as an identifying feature. Sperm are ejaculated from the cloaca around the spicule, rather than through it. The sperm produced by nematodes is amoeboid and is very motile, employing the same locomotion mechanism as seen in amoeboid species.

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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

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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====

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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.

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~~=== Recognition Features ===~~

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*The sexes are separate:

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**the female tail generally ends in a blunt point

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**males usually have two chitinous rods that can be protruded through the cloaca to hold the female - these are called spicules and, being chitinous, are easily seen under the microscope. As these differ in shape and size between species, they are very useful in identification

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*The '''bursate nematodes''' are characterised by a large expansion of the cuticle of the male tail to form a clasping organ (the bursa)

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*The heads of some nematodes have structures such as:

=== Feeding Habits ===

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