Neurotransmitter Basics
Neurotransmitters are chemical messengers used by the nervous system to transmit signals from one neuron (nerve cell) to another across a synapse. They play crucial roles in regulating virtually all bodily functions and mental processes.
Inhibitory vs. Excitatory Neurotransmitters
Neurotransmitters can be broadly classified based on their effect on the postsynaptic neuron:
- Inhibitory Neurotransmitters: These reduce the likelihood that the neuron will fire an action potential. They essentially calm the nervous system down.
- Excitatory Neurotransmitters: These increase the likelihood that the neuron will fire an action potential. They stimulate the nervous system.
Some neurotransmitters can be both, depending on the receptor they bind to, but many have a primary role.
Analyzing the Options
Let's examine the roles of the neurotransmitters listed:
Option 1: Epinephrine
Epinephrine (also known as adrenaline) is primarily a hormone involved in the body's stress response (the "fight or flight" response). While it can act as a neurotransmitter in the brain, it's often considered excitatory or modulatory, increasing alertness and arousal.
Option 2: Glutamate
Glutamate is the most abundant neurotransmitter in the central nervous system and is the principal excitatory neurotransmitter. It plays vital roles in learning and memory but is not an inhibitory neurotransmitter.
Option 3: GABA
GABA stands for Gamma-Aminobutyric Acid. It is the chief inhibitory neurotransmitter in the mature vertebrate central nervous system. GABA works by decreasing neuronal excitability throughout the nervous system. It helps reduce anxiety, calm nerves, and promote relaxation.
Option 4: Nor epinephrine
Norepinephrine (also known as noradrenaline) is closely related to epinephrine and also plays a role in the stress response. It acts as both a hormone and a neurotransmitter, primarily involved in vigilance, arousal, and attention. It is generally considered excitatory or modulatory.
Conclusion
Based on the analysis, GABA (Gamma-Aminobutyric Acid) is the primary inhibitory neurotransmitter among the choices provided. It functions to reduce neuronal excitability.
Important Questions from Miscellaneous
- List-I with List-II:
List-I
(Relief Materials)List-II
(Color Code)A. Shelter I. Yellow B. Clothes II. Khaki C. Food III. Red D. Medicine IV. Brown
Choose the correct answer from the options given below: - What was a key reform introduced by the Waqf (Amendment) Act, 2025?
Which of the following is NOT a state function or state variable in a thermodynamic system?
- What is the full form for "BPL" in Socio-economic aspects?
- In October 2024, which of the following companies was awarded the contract for design, manufacturing and commissioning of two high-speed trainsets by Integral Coach Factory (ICF) to be used in India's first bullet train between Mumbai and Ahmedabad?
