Which of the following correctly represents the sequence of components in a typical reflex arc?

• A. Integration center → Sensory neuron → Receptor → Motor neuron → Effector
• B. Sensory neuron → Receptor → Integration center → Effector → Motor neuron
• C. Receptor → Sensory neuron → Integration center → Motor neuron → Effector
• D. Effector → Motor neuron → Integration center → Sensory neuron → Receptor

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the concept of a reflex arc. A reflex arc is the neural pathway that controls a reflex action. It typically involves five main components: receptor, sensory neuron, integration center, motor neuron, and effector.
2. Step 2: Define each component in the reflex arc: - Receptor: Detects the stimulus (e.g., pain, temperature, pressure). - Sensory neuron: Transmits the signal from the receptor to the integration center. - Integration center: Processes the information, typically located in the spinal cord or brain. - Motor neuron: Carries the response signal from the integration center to the effector. - Effector: Executes the response (e.g., muscle contraction or gland secretion).
3. Step 3: Analyze the given sequences and compare them to the correct order of components in a reflex arc. The correct sequence is: Receptor → Sensory neuron → Integration center → Motor neuron → Effector.
4. Step 4: Eliminate incorrect options by identifying sequences that do not follow the logical flow of information in a reflex arc. For example, sequences that place the effector or motor neuron before the integration center are incorrect.
5. Step 5: Confirm the correct sequence by ensuring it aligns with the physiological process of a reflex arc, where the stimulus is detected by the receptor, transmitted via the sensory neuron, processed in the integration center, and responded to by the motor neuron and effector.