Plants rely on many different structures and chemicals to defend themselves from herbivores. Some, such as poison ivy, make chemicals on their surface that cause a severe skin reaction. Others produce toxic sap or other fluids that poison any animals that take a bite.

Which of the following examples uses structural defenses for protection?

Question 10 options:

African acacia tree releasing a ethylene gas

vine of poison oak

thorny rose bush

patch of green grass

thorny rose bush