3 When the number of living things in a food chain changes, what will happen to the food chain itself? 1. In a food chain, which living things have the smallest number, producers, plant-eating animals or meat-eating animals? Why? 2. Look at the two situations below. How will the food chain change? Circle the correct answers.
Situation 1
Humans hunt a large number of wolves. What will happen to the number of rabbits? What will happen to the number of plants?
number of plants increases / decreases
number of rabbits increases / decreases
number of wolves increases / decreases
Situation 2
What will happen to the food chain on the grassland when people keep spraying insecticide?
number of plants increases / decreases
number of worms increases / decreases
number of birds increases / decreases
number of snakes increases / decreases
Humans use insecticide to kill harmful insects. However, the toxic substances of insecticide can transfer from insects to insect-eating animals (such as birds) and accumulate up the food chain, affecting the health of meat-eating animals (such as snakes) at higher levels.
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