The video discusses how plants defend themselves against external threats, including physical, chemical, and mechanical defenses. It covers signs of plant diseases, such as stunted growth and discoloration, and methods to identify these diseases. The video also explains different types of pathogens, including viral, fungal, and insect threats, and how nutrient deficiencies can affect plants. Finally, it highlights various plant defenses, such as tough cell walls, waxy cuticles, antibacterial chemicals, and mimicry to deter herbivores.

Which of the following is NOT a method for identifying plant diseases?

• Consulting a laboratory

• Using a testing kit with monoclonal antibodies

• Using a gardening manual

• Observing animal behavior

What is a common symptom of a plant infected with a viral pathogen?

• Presence of aphids

• Yellowing and dropping of leaves

• Mosaic pattern of discoloration

• Stunted growth

Which mineral deficiency causes chlorosis in plants?

• Calcium deficiency

• Iron deficiency

• Magnesium deficiency

• Nitrate deficiency

What is the role of waxy cuticles on plant leaves?

• To enhance photosynthesis

• To stop pathogens from entering

• To prevent water loss

• To deter herbivores

How do some plants use mimicry as a defense mechanism?

• By producing antibacterial chemicals

• By curling leaves when touched

• By appearing as more dangerous plants

• By having tough cell walls