Plants cannot run away from danger like most animals can, so they have developed their own weapons and armour in order to protect themselves. To deter larger animals some plants have sharp spines or thorns, while others have leaves that sting or are bitter to taste. Cacti spines can be up to 15cm (6in) long.

Well, plants protect themselves from intense heat by producing smaller leaves (spines in cactus), by using water-saving methods of photosynthesis (such as Crassulacean acid metabolism), by growing protective hairs to deflect sunlight, or by producing thin leaves that cool down easily in a breeze or waxy leaves that …

Cacti generally have thick herbaceous or woody chlorophyll-containing stems. Cacti can be distinguished from other succulent plants by the presence of areoles, small cushionlike structures with trichomes (plant hairs) and, in almost all species, spines or barbed bristles (glochids).

By shading the cactus, these spines also help prevent the cactus from losing water through evaporation. So all in all, spines are adaptations that protect and help cacti hide from animals that may want to eat them. They also provide shade for the plant, which keeps them cooler and limits water loss.

In cacti, spines are wholly transformed leaves that protect the plant from herbivores, radiate heat from the stem during the day, and collect and drip condensed water vapour during the cooler night.

Cacti have a variety of uses: many species are used as ornamental plants, others are grown for fodder or forage, and others for food (particularly their fruit).

If you are looking to improve your air quality, you should get a cactus. After dark, a cactus will absorb the carbon dioxide in the atmosphere and then release oxygen. Not only does this mean you have better air quality being inhaled into your body, but the extra boost of oxygen helps you to sleep better.

Glochids or glochidia (singular “glochidium”) are hair-like spines or short prickles, generally barbed, found on the areoles of cacti in the sub-family Opuntioideae.

If not completely removed, cactus spines can cause complications such as inflammation, infection, toxin mediated reactions, allergic reactions and granuloma formation.