3.3

• What can studying symptoms help identify in plants?

  The disease without the need for tests
• What are some visible symptoms of plant disease?

  Abnormal or stunted growth, rot, discolouration, spots on leaves
• What are the methods of identifying plant disease?

  • Studying symptoms
  • Testing in lab
  • Using monoclonal antibody test kits
  • Consulting gardening manuals/websites
• What are some causes of plant disease?

  Nutrient deficiencies, viral, bacterial, or fungal pathogens
• What is an example of a viral pathogen affecting plants?

  Tobacco mosaic virus
• What is an example of a fungal pathogen affecting plants?

  Black spot
• What is nitrate deficiency in plants associated with?

  Stunted growth due to nitrates being used in protein synthesis
• What is magnesium deficiency in plants associated with?

  Chlorosis due to magnesium being needed to make chlorophyll
• What are the plant defenses against diseases?

  • Chemical defenses (antibacterial chemicals)
  • Mechanical defenses (thorns and hairs)
  • Physical defenses (cellulose cell walls, waxy cuticle)
  • Mimicry
  • Poisons
• What is a common insect that can cause plant disease?

  Aphids
• How do plant defenses like thorns and hairs function against pests?

  They physically deter herbivores from feeding on the plant
• What is the role of a waxy cuticle in plant defense?

  It acts as a barrier to prevent pathogen entry
• What is the significance of cellulose cell walls in plants?

  They provide structural support and protection against pathogens
• How can gardening manuals or websites assist in identifying plant diseases?

  They provide information on symptoms and treatment options
• What is the purpose of monoclonal antibody test kits in plant disease identification?

  To detect specific pathogens in plants
• What are the visible signs of pathogens in plants?

  Bacterial slime or eggs on plant surfaces
• What does abnormal or stunted growth in plants indicate?

  It may indicate nutrient deficiencies or disease
• What is the role of antibacterial chemicals in plant defenses?

  They help to inhibit the growth of bacteria
• What is the significance of leaf responses in plant defense?

  They help the plant adapt to environmental stressors and threats