[Campbell Biology P.917] Which of the following descriptions accurately represent plant defe... | Practice Question

Which of the following descriptions accurately represent plant defense mechanisms observed at the organ level? Select all that apply

  • A: Spines, as modified leaves, provide mechanical defense by causing pain.
  • B: The snowflake plant's leaf (Trevesia palmata) appears partially eaten to make it less attractive to herbivores.
  • C: Egg mimicry, such as that seen in Passiflora, involves leaf glands imitating insect eggs to dissuade egg-laying.
  • D: Bristles on cactus spines are examples of modified stems that tear flesh.
  • E: Tough sclerenchyma fibers found in olive leaves deter herbivores by being difficult to chew.

Explanation

Organ-level defenses include modifications of plant organs. Spines are modified leaves, and thorns are modified stems, both providing mechanical defense. The snowflake plant's leaf shape gives the appearance of being partially eaten. Egg mimicry, seen in Passiflora, involves leaf glands resembling insect eggs to deter egg-laying. Sclerenchyma fibers are tissue-level defenses.