Which of the following is the correct sequence of components in a simple spinal reflex arc?

• A. Effector, Motor Neuron, Interneuron, Sensory Neuron, Receptor
• B. Interneuron, Receptor, Sensory Neuron, Motor Neuron, Effector
• C. Sensory Neuron, Receptor, Motor Neuron, Interneuron, Effector
• D. Receptor, Sensory Neuron, Interneuron, Motor Neuron, Effector

Answer: (D)

Verified step by step guidance

1. Understand the concept of a spinal reflex arc: A spinal reflex arc is a neural pathway that controls a reflex action. It involves several components that work in sequence to produce a quick response to a stimulus.
2. Identify the first component: The sequence begins with the receptor, which detects the stimulus. Receptors are specialized cells or nerve endings that respond to specific types of stimuli, such as touch, temperature, or pain.
3. Determine the role of the sensory neuron: After the receptor detects the stimulus, the sensory neuron carries the information from the receptor to the spinal cord. Sensory neurons are responsible for transmitting sensory information to the central nervous system.
4. Recognize the function of the interneuron: Within the spinal cord, the sensory neuron communicates with an interneuron. Interneurons are responsible for processing the information and determining the appropriate response. They act as a relay between sensory and motor neurons.
5. Identify the final components: The interneuron then communicates with a motor neuron, which carries the response signal from the spinal cord to the effector. The effector, typically a muscle or gland, performs the reflex action, such as contracting a muscle or secreting a substance.