ITS NOT EVEN A DOCTOR NOR A ENGINEER IT JUST DID WHAT IT WAS COMMANDED TO DO
There are two types of neurons in our legs: motor neuron and sensory neuron. These send and receive messages to and from each other and the brain.
After Ed's accident, he can't move his injured leg since the motor neuron is dysfunctional. The sensory neuron is functional so he can feel his limbs but can't move them since when the sensory neuron sends a message to the motor neuron, it isn't able to deliver the message to the brain to make the leg move. This is why he can still feel his limbs but is not able to move them.
The invading bullfrogs ARE HARMFUL. This is because, they cause decline in the population of the native species.
Decline in the population of the native species will throw the ecosystem into a condition of imbalance which will eventually affect all the living organisms that are living in that ecosystem.
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