Question

What are reflex actions? Give two examples. Explain a reflex arc.

Answer 1

Reflex Action:

1. Living organisms need to adapt to changing environments to survive.
2. The nervous system helps to respond quickly to these changes by a phenomenon called reflex action.
3. Reflex action is an immediate, involuntary response to a stimulus to protect our body from harm.
4. The three types of neurons involved in a reflex action are sensory, motor, and relay neurons.

Examples of reflex action:

1. Pulling the hand or leg away when pricked by a pin
2. Blinking of eyes when an object such as a fly comes in front of our eyes.

Reflex Arc:

1. A reflex arc is a neural mechanism that represents the path traveled by a reflex.
2. The receptor detects the stimulus (for example, the prick of a pin).
3. The sensory neuron sends the message to the relay neuron, which is located in the spinal cord.
4. The motor neuron receives the message from the brain and sends it to the effector (skeletal muscle) to produce the desired response.
5. The pathway is shown in the flowchart below: