Simplest reflex action in human is

Options

A. Mono synaptic
B. Bi synaptic
C. Tri synaptic
D. Poly synaptic

Answer

To determine the simplest reflex action in humans, we need to understand the different types of synaptic reflexes based on the number of synapses involved. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand Reflex Actions
Reflex actions are automatic responses to stimuli that do not require conscious thought. They involve the nervous system and can be classified based on the number of synapses.

### Step 2: Define Synaptic Types
- **Monosynaptic Reflex**: This involves only one synapse between two neurons (one sensory neuron and one motor neuron).
- **Bisynaptic Reflex**: This involves two synapses, meaning there is an additional interneuron between the sensory and motor neurons.
- **Trisynaptic Reflex**: This involves three synapses, indicating two interneurons.
- **Polysynaptic Reflex**: This involves two or more synapses, which may include multiple interneurons.

### Step 3: Identify the Simplest Reflex
The simplest reflex action is characterized by the least complexity, which is found in the monosynaptic reflex. In this case, the reflex arc consists of only one sensory neuron and one motor neuron connected by a single synapse.

### Step 4: Conclusion
Based on the definitions and the characteristics of each type of reflex, the simplest reflex action in humans is the **monosynaptic reflex**.

### Final Answer
The answer to the question is **A. Monosynaptic**.

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