Immunology | Immune system| Immunity

* Sting Apparatus:
* Poisonous and non-poisonous snakes are distributed in all major continents of the world.
* In India,poisonous snakes found are trait,viper,pit viper,cobra,king cobra and all marine snakes.
* The poison duct opens at the tip of the fangs.
*  The poison apparatus consists of a pair of venom gland,a pair of venom ducts and a pair of large pointed fangs.
* The venom gland is located superficially behind the eye of the snake.

* Venom:
* The snake venoms are mixtures of proteins,polypeptides and enzymes.
* The venoms of snakes can be categorised based upon the area they affect.
* They categorised as neurotoxins,Cardiotoxins,Necrotics and Haemolytic venoms.
* Neurotoxins that affect the brain include Proteases,Invertases,DNAases,RNAases.
* Cardiotoxins that affect the heart include vasoconstrictors,vasodilators,serotonic,prostaglandins.
* Necrotics caused by the snake venom include collagenases,hyaluridases,invertases,DNAases,RNAases.

* Effects:
* In snake bite there is rapid swelling and decoloration at the site of bite.
* This is followed by further swelling that may extend all over the body.
* The victim shows signs of vomitting,nausea and diarrhea.In some cases death is caused due to shock.
* The swelling is extremely sensitive to touch and painful.
* When the heart is affected the pulse are weak and is fall in systemic arterial blood pressure.
* when CNS is affected respiratory paralysis in severe cases of poisoning is seen.
* Due to snake bites interference in breathing and eating is experienced.
* Sometimes a blood stained froth is discharged from the nose due to heavy tissue destruction.
* The healing wound is very slow because necrosis causes