Tuesday 5 June 2012

POISON APPARATUS-SNAKE

The poisonus snake include <1>poison gland <2>ducts <3>fangs <4>muscles.
<1>POISON GLAND-The sac like poison gland is situated  on either side of upper jaw, below the eyes .The are modified superior labial or parotid glands. The gland be small and oval ,large or tubular .The gland is sticky ,encapsulated with fibrous connective and mostly covered by a fan-shaped constrictor muscle,as temporal or masseter.Its stretching during biting squeezes poison from gland into its duct.
<2>POISON DUCTS-The poison duct leads anteriorly from poison gland to the base of a poison fang to enter its groove .
<3>FANGS-The fangs are certain specialized teeth attached to maxillary bones.Fangs are long,curved ,sharp and pointed.They use hypodermic needles for injecting poison into the body of victim.The fangs occur in poisonous snakes.
<a>SOLENOGLYPHOUS-The large functional fang occurs on the front of each maxilla.The base is covered with reserve and developing fangs.The fangs are movable and turned to lie to the roof of mouth .The hollow poison canal lined with enamel runs through the fangs opening at the tip.e.g vipers,rattle.
<2>PROTEROGLYPHOUS- The front of maxillae are permentely erect, the fangs are small. Each fang is grooved all along its anterior face.e.g cobras,kraits, coral snakes and sea-snakes.
<3>OPISTHOGLYPHOUS-The fangs are small,lie at the back of maxillae .e.g family colubridae.

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