Most cacti's natural defenses are simply numerous sharp spines all over it, however some have poisonous/acidic sap inside it which it can fill its spines with or even (in a few cases) regurgitate it upon its attackers.
it has a hard shell
by roaring
because it is water proof
Cactus grow very slow because it is saving water for the later time. Cactus grow in the desert, and it merely rains in deserts. So, when it does rain, the cactus takes up as much as water as it can and saves it for the rest of the period of time until it rains again, which is why they grow slowly. They use small amounts of water for itself everyday, which makes it grow slower.
It hides where his predator can not see him
A cactus adapts to its environment by losing its spines to reduce water loss and protect itself from animals.
The waste product found in cactus plants is usually latex, which can ooze out if a cactus is damaged or wounded. This sticky, milky substance helps the cactus protect itself from predators and heal its wounds.
Cactus itself!
By hanging around cactuses or cacti so the spikes can keep their predators away.
they have the spines to protect them from your face
A cactus has skin, or a thick waxy outer layer called a cuticle, to prevent water loss through evaporation and protect itself from extreme temperatures and predators in its arid environment. This adaptation helps the cactus survive in its harsh habitat by conserving water and reducing the risk of damage.
Create a reservation and keep people out of it.
Within the protection of the cactus needles.
how do young protect itself
Yes, because based on research, cactus has an ability to lessen the radiation from computer, so best if you'll be putting a cactus beside of your computer.
The cactus adapted to its harsh environment by developing thick skin to slow the evaporation of water. The leaves changed in order to reduce the surface area that water could evaporate from and over time became defensive spines to protect itself from animals trying to get inside its thick skin for the moisture. The cactus makes its food, by having chlorophyll throughout the rest of plant. That is why the entire cactus is green.
how does 'what' protect itself.