Biology

Nervous System and Neurons

1,164 Questions

The nervous system and neurons section covers the structural and functional aspects of the human nervous system. Topics include nerve fibers, the myelin sheath, and sympathetic nervous system functions. This material is crucial for general science preparation in various competitive exams.

Neuron structureMyelin sheath productionSympathetic nervous systemCranial and spinal nervesParasympathetic functions

Nervous System and Neurons Questions

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

A ramus communicans consists of

  1. White ramus only

  2. Grey ramus only

  3. Both A and B

  4. Red ramus only
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ramus communicans is the branch which connects the spinal nerve and the sympathetic trunk.  There are two forms of ramus communicans. They are gray ramus communicans and white ramus communicans. They are responsible for conduction of signals in the sympathetic nervous system. The white rami communicans are the preganglionic sympathetic outflow from the spinal cord. The gray rami communicans contain postganglionic nerve fibers of the sympathetic nervous system and are composed of largely unmyelinated neurons.

So, the correct answer is option C. 

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Preganglionic parasympathetic fibres arise from ................. spinal segments.

  1. Thoracic and lumbar

  2. Thoracic and sacral

  3. Brain and lumbar

  4. Brain and sacral

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Parasympathetic nerve fibres arise from the central nervous system with the $S _2$, $S _3$, and $S _4$ spinal nerves and from the third, seventh, ninth, and tenth cranial nerves. Because of its location, the parasympathetic system is commonly referred to as having craniosacral outflow.

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Vagus nerve is composed mainly of parasympathetic fibres. The preganlionic fibres form a net work in the walls of the organs. This network is known as

  1. Choroid plexus

  2. Nervous plexus

  3. Auerbach plexus

  4. Brachial plexus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Auerbach plexus is the interwoven network of the vagus nerve in the inner circular and outer longitudinal muscles of the muscularis layer of the visceral organs. 

A. The choroid plexus is present in the ventricles of the brain.
B. Nervous plexus is the bundle of the neurons.
C. Auerbach plexus is present in the muscularis of the visceral organs.
D. Brachial plexus is present in the spinal cord formed by four lower cervical spinal nerves and the first thoracic spinal nerve.
Hence, the correct answer is 'Auerbach plexus'

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

The self governing nervous system is known as

  1. Central nervous system

  2. Peripheral nervous system

  3. Autonomic nervous system

  4. Sympathetic nervous system
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The peripheral nervous system is that connects the body organs with brain and the spinal cord is divided into two parts:

  1. Somatic nervous system: The neurons of this system innervate those muscles that are controlled by the voluntary consciousness for example, muscles of limbs, neck, tongue etc.
  2. Autonomic nervous system: The neurons of this system innervates the visceral organs and their effects are not controlled by the conscious brain. They function involuntarily. So, these are the self-governing part of the nervous system. The sympathetic and parasympathetic nervous system are classified under the autonomic nervous system.
Hence, the correct answer is 'Autonomic nervous system'

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro-hormonal control system?

  1. Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal medulla

  2. Neurotransmitters diffuse rapidly across the cleft and transmit a nerve impulse

  3. Hypothalamus activates the parasympathetic division of brain

  4. Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal cortex.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Epinephrine and norepinephrine are released by the adrenal medulla and nervous system respectively. They are the flight/fight hormones that are released when the body is under extreme stress. They are also called as emergency hormone as it initiates quick reaction which makes the individual to think and respond quickly to the stress. The hormone increases metabolic rate. Dilation of blood vessels going to heart and the brain occurs. So, the correct answer is option A.

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Comparing the somatic nervous system with the autonomic nervous system, which of the following statement is true?

  1. Autonomic nervous system produces involuntary movement in skeletal muscle

  2. Somatic nervous system produces voluntary movement in glands and smooth muscle

  3. Autonomic nervous system produces voluntary movement in smooth muscle and glands

  4. Autonomic nervous system produces involuntary movement in smooth muscle, viscera and glands
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The autonomic nervous system is the part of the nervous system that supplies that internal organs, including the blood vessels, stomach, intestine, liver, kidneys, and digestive glands.

So, the correct option is 'Autonomic nervous system produces involuntary movement in smooth muscle, viscera and glands'.

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Parasympathetic nervous system is also termed as

  1. Visceral

  2. Thoracico-lumbar

  3. Cranio-sacral

  4. Mesenteric
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The parasympathetic nervous system is a division of the autonomic nervous system. The preganglionic nerve fibres of this system arise from the brain which includes cranial nerves III, VII, IX and X, that is, the oculomotor, facial, glossopharyngeal and vagus nerves, as well as from the sacral region of the spinal cord, that is, ramus communicans 2, 3 and 4. The sympathetic nervous system is called the thoracico-lumbar.

Hence, the correct answer is 'Cranio-sacral'

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Which of the following is not true concerning the autonomic nervous system?

  1. Sympathetic responses include fight-or-flight responses

  2. Sympathetic responses are generally widespread throughout the body

  3. It includes sensory pre- and postganglionic fibres

  4. Autonomic division is entirely motor
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The autonomic nervous system is the part of the nervous system that supplies internal organs, including the blood vessels, stomach, intestine, liver, kidneys, and digestive glands.

So, the correct option is 'It includes sensory pre- and postganglionic fibres'.

Multiple choice biology nervous system of man divisions of nervous system autonomic nervous system the human brain

Choose the correct answer from the alternatives given.
All visceral effectors are innervated by both the parasympathetic and sympathetic divisions of the autonomic nervous system for coordinating various activities of the body This concept is known is

  1. sensory/motor regulation

  2. dual innervation

  3. autonomic summation

  4. neurotransmitter trade-off
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There is a dual innervation of most organs of the body by the sympathetic and parasympathetic divisions of the ANS. The connection of both systems with the hypothalamus and higher brain areas have been omitted.

So, the correct option is 'dual innervation'.

Multiple choice biology windows of knowledge human tongue organ of taste tongue : the organ of taste

Injury to vagus nerve will not affect

  1. Gastrointestinal movements

  2. Tongue movements

  3. Cardiac movements

  4. Pancreatic secretion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The vagus nerve (cranial nerve X) is involved in parasympathetic control of the heart, lungs, and digestive tract. Tongue movements are controlled by the hypoglossal nerve (cranial nerve XII), not the vagus nerve.

Multiple choice biology windows of knowledge human tongue organ of taste tongue : the organ of taste

Receptor absent over tongue is

  1. Thermoreceptor

  2. Gustatoreceptor

  3. Photoreceptor

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Thermoreceptors sense temperature change and are present on tongue and skin.
B.  Gustatoreceptors are taste buds present on tongue which sense different tastes.
C. Photoreceptors are the cells that are associated with coloured vision and vision under daylight and low light They are present in eye.
So, the correct answer is 'Photoreceptor'.
Multiple choice biology windows of knowledge human tongue organ of taste tongue : the organ of taste

Tongue has

  1. Baroreceptors

  2. Olfactoreceptors

  3. Gustatoreceptors

  4. Tangoreceptors
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Baroreceptors are mechanoreceptors present in the blood vessels and sense pressure changes.
B. Olfactoreceptors are present in nasal cavity and sense smell.
C. Gustatoreceptors are taste buds present on tongue and sense different tastes.
D. Tangoreceptors are present on skin surfaces and sense touch.
So, the correct answer is 'Gustatoreceptors'.
Multiple choice zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

Centre of autonomic nervous system is located in?

  1. Hypothalamus

  2. Medulla Oblongata

  3. Cerebellum
  4. Both $(1)$ and $(2)$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The nervous system in humans controls a variety of functions. The central nervous system and the peripheral nervous system are the two major parts of the nervous system. The peripheral nervous system is further of two types- the somatic nervous system and the autonomic nervous system. The somatic system controls the sense organs and voluntary muscles. The autonomic nervous system controls the internal organs and glands of the body. The hypothalamus acts as the center of the autonomic nervous system and controls its activities.
So the correct answer is 'Hypothalamus'.
Multiple choice zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

Sympatheticnervous system is also called 

  1. visceral nervous system

  2. thoraco-lumber nervous system

  3. cranio-sacral nervous system

  4. mesentaric nervous system
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The sympathetic nervous system is called the thoraco-lumbar outflow because its preganglionic neurons originate in the thoracic and lumbar segments of the spinal cord.

Multiple choice zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

In mammals, the autonomic system is composed of

  1. Sympathetic and parasympathetic nerves

  2. Cranial and spinal nerves

  3. Brain and spinal cord

  4. Medullated and non-medullated nerves
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The nervous system is divided into two major divisions, central and peripheral nervous system. 

The centrally located central nervous system includes brain and spinal cord. Peripheral nervous system includes all cranial and spinal nerves. 
Peripheral nervous system is further divided into somatic and autonomous divisions. The autonomous nervous system has two divisions; sympathetic and parasympathetic divisions, which have opposite functions. 
The nerve fibres are classified as myelinated and non myelinated fibres on the basis of presence or absence of myelin sheath. Myelinated fibres are present in the white matter of brain and spinal cord as well as in cranial and spinal nerves. Non-myelinated fibres are present in autonomous nerves system.