Structural and functional unit of nervous system is-

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2022

Explanation

The neuron, or nerve cell, is defined as the basic structural and functional unit of the nervous system.
It is a highly specialized cell responsible for receiving, processing, and transmitting information to other cells via electrical and chemical signals.
The entire communication network of the nervous system, from simple reflexes to complex thoughts, is built upon the function of individual neurons.

Option A: An axon is only a part of a neuron. It is the long, slender projection that conducts electrical impulses away from the neuron's cell body.
Option B: The brain is a complex organ of the central nervous system. It is composed of billions of neurons and glial cells, but it is not the basic, single unit.
Option C: A dendron (or dendrite) is a branched projection of a neuron that receives electrochemical stimulation from other neurons.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Basic structural and functional unit of the nervous system as background academic context rather than a clinical decision trigger.
Understanding the neuron as the basic unit is fundamental to neurology. Diseases like Multiple Sclerosis (damage to the myelin sheath) or Alzheimer's disease (neuron degeneration) directly impact these cells.
Many pharmacological treatments for mental health and neurological disorders work by targeting processes at the neuronal level, such as neurotransmitter release and reuptake at the synapse.
Nerve injury and regeneration depend on the health and integrity of individual neurons and their components.

How to Approach the Question

First, identify the keywords in the question: 'structural and functional unit' and 'nervous system'. This asks for the most basic building block that also performs the main job of the system.
Next, consider each option in relation to this definition.
Evaluate 'Axon' and 'Dendron'. Recognize these are parts of a larger cell, not the complete unit itself.
Evaluate 'Brain'. Recognize this is a large, complex organ made of many smaller units, not the basic unit.
Evaluate 'Neuron'. Recall or deduce that the neuron is the scientific name for the nerve cell, which is the fundamental unit of the nervous system. This option encompasses the others (axon, dendron) as its components.
Select 'Neuron' as it is the most accurate and comprehensive answer.

Concept Tested & Keywords

QuQ-sE5vYCAi-N7wcpnLAx

E6 Physiology Essentials Sembulingam 10e Part 3 p. 34-36

E6 Anatomy Applied Ashalatha 4e p. 402-404

E6 Psychology Baron Misra 5e Part 1 p. 61-63

Practise the full RUHS, Jaipur, PB B.Sc Nursing Entrance-2022

Attempt every question from this paper in a timed mock, then review the full solution for each one.