Reflex arcs are a concept in biology, not chemistry. Here's how you can remember the stages of a reflex arc:

Think of it as a chain reaction:

1. Stimulus: Imagine a hot stove as the stimulus, like a sudden change in temperature.

2. Receptor: Think of your hand as the receptor, feeling the heat.

3. Sensory Neuron: Picture a messenger running from your hand to your brain, carrying the "hot!" message.

4. Integration Center (Spinal Cord): Imagine a central hub where the message gets processed and a decision is made ("move your hand!").

5. Motor Neuron: Picture another messenger running back from your brain to your hand, delivering the "move!" command.

6. Effector: Your hand muscles are the effector, actually moving away from the stove.

Mnemonic: You can use the acronym "SRISME" to remember the stages:

* Stimulus

* Receptor

* Integration Center

* Sensory Neuron

* Motor Neuron

* Effector

Let me know if you'd like to learn more about reflex arcs or other biology topics!