thorn

(noun)

a sharp, protective spine of a plant

Related Terms

Examples of thorn in the following topics:

  • Plant Defenses Against Herbivores

    • Other adaptations against herbivores include hard shells, thorns (modified branches), and spines (modified leaves).
    • Some Acacia tree species have developed mutualistic relationships with ant colonies: they offer the ants shelter in their hollow thorns in exchange for the ants' defense of the tree's leaves.
    • The large thorn-like stipules of Acacia collinsii are hollow and offer shelter for ants, which in return protect the plant against herbivores.

  • Stem Modifications

    • Thorns are modified branches appearing as hard, woody, sharp outgrowths that protect the plant; common examples include roses, osage orange, and devil's walking stick.
    • (b) Thorns are modified branches.

  • Other Fungi Involved in Respiratory Disease

    • Because roses can spread the disease, it is one of a few diseases referred to as rose-thorn or rose-gardeners' disease.

  • Predation, Herbivory, and the Competitive Exclusion Principle

    • Mechanical defenses, such as the presence of thorns on plants or the hard shell on turtles, discourage animal predation and herbivory by causing physical pain to the predator or by physically preventing the predator from being able to eat the prey.
    • The (a) honey locust tree (Gleditsia triacanthos) uses thorns, a mechanical defense, against herbivores, while the (b) Florida red-bellied turtle (Pseudemys nelsoni) uses its shell as a mechanical defense against predators.

  • Herbivory and Pollination

    • Spines and thorns deter most animals, except for mammals with thick fur; some birds have specialized beaks to get past such defenses .

  • Gothic Architecture: La Saint-Chapelle

    • It was commissioned by King Louis IX of France to house his collection of relics of the passion, including the Crown of Thorns - one of the most important relics in medieval Christendom.

  • Characteristics of Helminths

    • These attachment organs include bothria (sucking grooves: Cestodes or tapeworms, which may also have a rostellum (crown of thorns with hooks); Old World Hookworms: cutting teeth; New World Hookworms: cutting plate.

  • Plant Adaptations to Life on Land

    • In turn, plants developed strategies to deter predation: from spines and thorns to toxic chemicals.

  • Marginal Analysis

    • As we pick more berries we have to reach further up or down and into the bushes where there are thorns.

  • Geometric Symbolism

    • A few examples include the Celtic cross, the rosary, the halo, the Crown of Thorns, and the labyrinth on the floor of Chartres Cathedral .