No.
Some may be considered as leaves but not really. Christmas cactus for instance grows in thin segmented stalks reminiscent of leaves. Cactus flowers have petal that are leafy and green like leaves but not really leaves. barrel cactus and saquaros obviously have no leafy protrusions beyond their flowers.
actually, One defining feature of cacti is having clusters of spines. Numerous plants have spines of course, but in cacti, spines occur in clusters in the axil of leaves, even though the leaves are usually microscopic. Most cactus morphologists have concluded that cactus spines are either modified leaves or modified bud scales (the difference is inconsequential because bud scales themselves are modified leaves).
Extremely carefully.
By evolution
Plants in different environments makes changes in its structure when it starts growing. These are adaptations. For example Cactus are made up of a fleshy leaves with no leaves except for thorns which plays an important role in reducing water through evaporation (transpiration). Pine trees as we know are conical and its leaves are needle-shaped so as to reduce water loss. Under various changes, their normal disposition changes. Their structure changes for the worse.
A cactus is a carnivore; they enjoy eating desert foxes and the odd rat or two.
An example of mutualism in a desert biome is the desert is the relationship between Saguaro cacti and the Gila woodpecker. This bird finds food like parasites and insects on the cactus. It also nests on cacti. While the cacti provide food and shelter for this bird, the bird in turn helps cacti when it spreads pollen to other cacti. Mutualism refers to a relationship in which both parties benefit from their interaction.
Leaves have evolved into spines on the cactus.
the leaves of a cactus help get the suns nutrition foe the plant to grow None pretty much and formally proper cactus have no leaves only it's convergently evolved cousins do.
A cactus has no leaves.
A cactus has no leaves but does have a stem.
cactus
A cactus leaves get sunlight and they make photosynthesis and they get water from that and they save the water
a cactus has spiny leaves for protection and so the water wont evaporate so easily.
Acanthus and cactus but cactus not really leafy :)
defence. the cacti leaves are the thorns...
The main difference between cactus and succulent is that cactus consists of areoles and no leaves whereas succulent contains fleshy leaves and no areoles.
A cactus stores water in its stem.
cactus