If they don't have venom, then they're not venomous snakes.
If the question is why some snakes don't inject venom on particular bites despite being members of a venomous species...
Some species can choose to release venom or not release venom. They may not inject venom on a "warning bite" and instead reserve it for hunting.
Other species always inject venom ... if they have any. But they may have recently bitten something else and used up the venom supply, and the glands that produce it haven't had time to "recharge" the supply yet.
No because some snakes are not poisnous at all
Absolutely. Non-venomous means exactly that... Species that don't employ venom to subdue their 'prey' usually employ the constriction method.
Not all snakes are poisonous. Some are constrictors which means that they bite their prey and wrap themselves around their food to suffocate the prey. Examples of constrictors are Ball Pythons and Anacondas. Poisonous snakes do have poison in their fangs though.
No snake is poisonous, though some are venomous. Garter snakes are technically very mildly venomous, but this venom is harmless to humans.
Yes, some venomous snakes lay eggs, while others give birth to live young.
Reptiles have something called 'passive limbisossis'. That means that they develop natural immunity to their own venom an the venom of other snakes of the same species. Some snakes such as the California Kingsnake are even immune to other snake venom's, since venomous snakes are a part of their diet.
It varies from snake to snake. Most will run if threatened. Some have venom as defense, some play dead, some bite, others pretend to be venomous snakes like cobras or rattlesnakes; some snakes will even whip their tail at predators in defense.
Snakes and other animals have incorporated toxins into their bodies for different reasons through evolution. Some have venom for defense, as a way to get away from or threaten a predator. Others are venomous for hunting prey down, weakening it before killing and eating it.
Nope - it depends on the individual species - some are live-bearers while others lay eggs.
Yes. The venom of venomous snakes is often lethal to that of other. The exception is that many snakes are resistant to their own species' venom. Snakes that are adapted to eating other snakes may also have some venom resistance.
Poisonous snakes cannot be kept as pets. Keeping a venomous snake with its venom sacks intact is dangerous. The venom sacks can be removed, but the snakes need to inject this venom into their prey to be able to digest it. The venom helps to break down the tissues of the snakes food. A de - vonomed snake will soon starve to death.Refer to Wikipedia for more information.EDITED: Actually, venomous snakes can be kept in captivity by an experienced keeper. They are most certainly not "pets" in the sense of something like a dog or cat, they are more like specimens in a collection.Snakes that have had their venom sacks removed are called "venomoid", and they can still live perfectly healthy lives. The myth that they need their venom to digest their food is false. However, the practice of venomoiding snakes is seldom done correctly, the only place that does it legally and correctly is Venomoid Inc. Venomoids should still be treated as fully venomous snakes, as if the procedure is done even a tiny bit incorrectly, the snake can still produce venom or in some cases regenerate their venom glands to some extent.
no….but they can make you hurt yourself running from it!