Spiders hold their prey with their legs. Spiders inject venom to paralyze their prey with their fangs. Spiders regurgitate fluid from their stomach's onto the prey and the fluid breaks down the nutrients which flow into the spider through its mouth. (We humans have internal processes for getting nutrients from food, spiders have external processes.
There are no unessential parts to spiders. If a body part is not for keeping the spider itself alive then it is for reproduction.
If you mean what parts do spiders use to protect themselves, the main thing is their fangs. However, some tarantulas have spines on their body that they can rub off with their hind legs. The spines act like the nastiest fiberglass insulation. If they get in a predator's eyes, nose, or mouth they can do much more than just make it itch.
Spiders use their bodies to dig burrows for protection, build webs for protection, and even to make underwater diving bells where they can rest without having to worry about anything.
All a spiders body parts are required for it to survive.
it uses its fangs/mouth
fangs , legs :)
fangs
cheeseburgers!
their paws
they use it to build body parts and make cells
your body digests food which turns it in to energy that goes through your bloodstream to all parts of your body
mouth or gills
Its balls
the ears
, beak ...
They use their strong claws to dig burrows and to find their food.
Proteins, vitamins, carbohydrates and minerals.
tell the body part using for getig food
They use their tongue to catch the food. They also push their eyes into their throat to swallow the food.