User:Abergabe/Snake venoms

Snake venoms are toxins secreted from the oral glands of some snakes.

toxin-secreting oral glands

The gland which secretes the zootoxin is a modification of the parotid salivary gland of other vertebrates, and is usually situated on each side of the head below and behind the eye, invested in a muscular sheath. It is provided with a large alveoli in which the venom is stored before being conveyed by a duct to the base of the channelled or tubular fang through which it is ejected. Snake venom is a combination of many different proteins and enzymes. Many of these proteins are harmless to humans, but some are toxins.

Note that snake venoms are generally not dangerous when ingested, and are therefore not technically poisons.[citation needed]

Source
It is now known found that venoms originated earlier than previously believed, and that all reptiles with toxin-secreting oral glands have a single ancestor which has lead to the current venom systems in lizards and snakes. Consequently, very little is known about when snake venoms where first developed, the evolutionary pressures which selected them, and physical diversifications behind the taxonomy.

The presence of enzymes in snake venom has led to the belief that it was an adaptation to assist in the digestion of prey,

However studies of the western diamondback rattlesnake, and of the Taiwanese pit viper, both snakes with highly proteolytic venom, show that envenomation has no impact on the time food takes to pass through the gut. More research is needed to determine the selective pressures that have armed snakes in this way.

Taxonomy of venomous snakes
Of the extant snakes, it is the family of Colubrid or 'advanced snakes' which are venomous.

Treatment
Snake bites are treated by