Food Chains and Predator-Prey Cycles

• How do the numbers of predators and prey change over time?

  They change in cycles
• What biotic factor affects organisms mentioned in the video?

  A source of food
• What do scientists call the first organism in a food chain?

  Producer
• What is the role of producers in food chains?

  They synthesize complex molecules
• What molecule do green plants make through photosynthesis?

  Glucose
• What is biomass in the context of food chains?

  Complex molecules passed down the food chain
• Who are the primary consumers in the food chains discussed?

  Rabbits and caterpillars
• What do we call animals that eat primary consumers?

  Secondary consumers
• In the food chain with four stages, who is the tertiary consumer?

  Bird of prey
• What is the definition of a predator?

  Consumers that kill and eat other animals
• In the first food chain, who is the prey?

  Rabbit
• What happens to the populations of predator and prey over time?

  They rise and fall in cycles
• What might cause the population of rabbits to increase?

  Warm summer with plenty of grass
• What happens to the fox population when the rabbit population decreases?

  Fox population also decreases
• What is a stable community?

  One where biotic and abiotic factors are balanced
• What can disrupt predator-prey cycles?

  A drought or new predator arrival
• Where can you find questions on food chains and predator-prey cycles?

  In the vision workbook
• What are the stages of a food chain?

  • Producer
  • Primary consumer
  • Secondary consumer
  • Tertiary consumer
• Describe the predator-prey cycle.

  1. Rabbit population increases
  2. Fox population increases
  3. Rabbit population decreases
  4. Fox population decreases
  5. Cycle repeats