Which of the following component is not common in all types of spinal reflexes ?

Options

A. Receptor
B. Effector
C. Interneuron
D. Sensory neuron

Answer

To answer the question "Which of the following components is not common in all types of spinal reflexes?" we need to analyze the components involved in spinal reflexes.

### Step-by-Step Solution:

1. **Understanding Spinal Reflexes**:
- Spinal reflexes are automatic responses that occur without conscious thought. They are mediated by the spinal cord.

2. **Identifying the Components of a Reflex Arc**:
- A reflex arc typically includes several key components:
- **Receptor**: Detects the stimulus (e.g., pain, heat).
- **Sensory Neuron**: Transmits the signal from the receptor to the spinal cord.
- **Interneuron**: (not always present) connects sensory neurons to motor neurons in the spinal cord.
- **Motor Neuron**: Carries the signal from the spinal cord to the effector.
- **Effector**: The muscle or gland that responds to the stimulus.

3. **Analyzing the Options**:
- The options given are:
- Receptor
- Effector
- Interneuron
- Sensory Neuron
- We need to determine which of these components is not common to all spinal reflexes.

4. **Evaluating Each Component**:
- **Receptor**: Common in all reflexes as it detects the stimulus.
- **Effector**: Also common in all reflexes as it produces the response.
- **Sensory Neuron**: Common in all reflexes as it transmits the signal to the spinal cord.
- **Interneuron**: Not present in all reflex arcs. Some reflexes (like monosynaptic reflexes) do not involve interneurons.

5. **Conclusion**:
- The component that is not common in all types of spinal reflexes is the **Interneuron**.

### Final Answer:
The component that is not common in all types of spinal reflexes is **Interneuron**.

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