Changes

The pharynx is situated at the anterior end of the nematode and is used in feeding, often being embedded into the epidermis or blood vessels of the worms predilection site. The pharynx may be specialized depending on the predeliction site and food type that the nematode requires, many blood feeders have teeth or plates used for attachment. The pharynx has a radial muscle that is used in pumping food into the intestines. The food enters the buccal capsule the size and shape of which is characteristic in some species of nematode. Due to the high pressure levels in the nematode body cavity there is a one way valve between the oesophagus and intestines and food is pushed through this by peristaltic action of radial oesophageal muscles.

The pharynx is situated at the anterior end of the nematode and is used in feeding, often being embedded into the epidermis or blood vessels of the worms predilection site. The pharynx may be specialized depending on the predeliction site and food type that the nematode requires, many blood feeders have teeth or plates used for attachment. The pharynx has a radial muscle that is used in pumping food into the intestines. The food enters the buccal capsule the size and shape of which is characteristic in some species of nematode. Due to the high pressure levels in the nematode body cavity there is a one way valve between the oesophagus and intestines and food is pushed through this by peristaltic action of radial oesophageal muscles.

Digestion occurs rapidly and faeces is expelled under pressure from the posterior of the nematode.  

The intestines of nematodes are simple tubes, only a single cell thick. The number of cells can range from 10's to one million and can be used as an identifying feature in some species. The cells are lined with microvilli, similarly to those in the mammalian gut, which are use to provide surface area for the absorption of nutrients. Lipid globules are also stored within the intestinal lumen and can occupy up to 50% of its volume. Digestion occurs rapidly and faeces is expelled under pressure from the posterior of the nematode.  

==Reproduction==

==Reproduction==

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

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

*The heads of some nematodes have structures such as:

*The heads of some nematodes have structures such as:

=== Feeding Habits ===

=== Feeding Habits ===