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

Given below are comparing the effects of sympathetic and parasympathetic nervous system for four features.
Which one feature is correctly described?

  1. Feature- Salivary glands, Sympathetic nervous system- Stimulates secretion, Parasympathetic nervous system- Inhibits secretion

  2. Feature- Pupil of the eye, Sympathetic nervous system- Dilates, Parasympathetic nervous system- Constricts

  3. Feature- Heart rate, Sympathetic nervous system- Decreases, Parasympathetic nervous system- Increases

  4. Feature- Intestinal peristalsis, Sympathetic nervous system- Stimulates, Parasympathetic nervous system- Inhibits
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sympathetic nervous system inhibits salivary gland secretion, accelerates the heart rate, decreases intestinal peristalsis and dilate the pupil of the eye. Whereas parasympathetic nervous system stimulates salivary gland secretion, slows heart rate, stimulates intestinal peristalsis and constricts pupil of the eye. The sympathetic and the parasympathetic nervous system are parts of the autonomic nervous system. These systems work in balance with each other and directly or indirectly affect almost every structure in the body. The sympathetic nervous system has an active "pushing" function, the parasympathetic has mainly a relaxing function.

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

Constriction of the pupil is function of

  1. Parasympathetic system

  2. Hypothalamus

  3. Thalamus

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Constriction of the pupil is the function of the parasympathetic system. The parasympathetic nervous system is one of the two divisions of the autonomic nervous system, the other is the sympathetic nervous system. The autonomic nervous system is responsible for regulating the body's unconscious actions. The parasympathetic system is responsible for stimulation of "rest and digest" or "feed and breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion and defecation. 

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

Select the wrong paired match from the following.

  1. CNS - Site of information processing and control

  2. PNS - Transmission of impulses to and from the CNS

  3. SNS - Relays impulses from the CNS to skeletal muscles

  4. ANS - Transmission of impulses from the CNS to voluntary organs
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The central nervous system (CNS) includes brain and spinal cord. It integrates and stores the sensory information from external and internal sense organs and commands different organs to respond accordingly. 

Peripheral nervous system (PNS) lies outside the central nervous system and consists of somatic and autonomic nervous system. Somatic nervous system (SNS) serves to carry the sensory information from external sensory receptors to CNS and motor signals from CNS to skeletal muscles (the voluntary actions). 
The autonomic division (ANS) of peripheral nervous system consists of motor fibres that relay nerve impulses from CNS to cardiac and smooth muscles and glands, thereby controlling the functioning of internal organs, without our conscious control (the involuntary actions). 
PNS relays information to and from CNS via its somatic and autonomic divisions.
Therefore, the correct answer is option D.

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

Which of the following is not a characteristic of the human sympathetic nervous system?

  1. Prepares the person for fight or flight

  2. Has ganglia near the spinal cord

  3. Increases heart beat

  4. Is a craniosacral division of the autonomic nervous system
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The human sympathetic nervous system controls the functions (for example accelerated heartbeat, reduced digestion rate etc) that help prepare the organism for the physical strain which is required to escape from a dangerous situation.

The preganglionic fibres of sympathetic nervous system arise from thoracic lumbar portion of spinal cord and immediately terminate in ganglia lying near the cord. 
Under stress conditions, preganglionic neurons of this system release acetylcholine which in turn makes postganglionic neurons to release norepinephrine causing increased heart beat.
Sympathetic nervous system is thoracic lumber division of autonomous nervous system. The parasympathetic system is its sacral division
So, the correct answer is 'Is a craniosacral division of the autonomic nervous system'

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

Which of the following systems slows the heart rate, constricts the pupil and stimulates pancreatic activity during emergency conditions?

  1. Enteric nervous system

  2. Somatic nervous system

  3. Peripheral nervous system

  4. Parasympathetic division

  5. Sympathetic division
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Parasympathetic nervous system slows the heart rate, constricts the pupil and stimulates pancreatic activity during emergency conditions.
The parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.
Heart rate is controlled by the two branches of the autonomic nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. 
The reduced heart rate results from an increase in activity of the parasympathetic nervous system, and perhaps from a decrease in activity of the sympathetic nervous system.
Examples of body functions stimulated by the parasympathetic nervous system  include sexual arousal, salivation, lacrimation, urination, digestion, and defecation. 
The parasympathetic nervous system is also known as the rest and digest activation, is the segment that assists with normal, autonomic functions. Typically all are in the control of the parasympathetic nervous system. Since this is the normal state of the body, the parasympathetic system is more active than the sympathetic system in controlling body functions.

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

Which of the following human parasympathetic function is not under the control of a cranial nerve?

  1. Contraction of bladder

  2. Constriction of pupil

  3. Increase of salivation

  4. Stimulation of gall bladder activity
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The parasympathetic nervous system decreases respiration and heart rate and increases digestion. Stimulation of the parasympathetic nervous systems results in the construction of pupils. Salivation, decrease heart rate and blood pressure.

So, the correct option is 'Contraction of bladder'.

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

How many pairs of sympathetic ganglia are present in ANS?

  1. 10

  2. 12

  3. 22

  4. 31.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sympathetic ganglia are the ganglia of the sympathetic nervous system. It's function is to deliver information to the body about stress and when the body is in danger, and are responsible for the fight-or-flight response. There are usually 21-23 pairs of these ganglia are present that is, 3 in the cervical region, 11 in the thoracic region, 4 in the lumbar region and 4-5 in the sacral region. So, the correct answer is option C.

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

An example of autonomous nervous system is

  1. Swallowing food

  2. Pillary reflex

  3. Peristalsis of intestine

  4. Knee-jerk response
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The autonomic nervous system controls the coordinated and involuntary movements of the body. The peristalsis of the intestine is an involuntary visceral movement which is controlled by the autonomic nervous system. 

A. Swallowing of food initially is controlled by the somatic nervous system.
B. Pupillary reflex is an unconditioned reflex.
C. Peristalsis of the intestine is controlled by the autonomic nervous system.
D. The knee-jerk response is a monosynaptic reflex action.
Hence, the correct answer is 'Peristalsis of intestine'.

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

The parasympathetic division of the autonomic nervous system:

  1. arises from the cranial and sacral spinal cord segments

  2. is concerned with conserving and restoring energy H

  3. has ganglia near or within visceral effectors

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The parasympathetic division of autonomic nervous system. The nerve fibres of this system arise from the brain, the cranial nerves and the sacrum of the spinal cord, the sacral nerves

The parasympathetic system is also called the rest and digest system as it stimulates digestion and assimilation
The efferent nerves of the parasympathetic nervous system form ganglia close to the visceral organs or the nerves are innervated in the visceral organs, resulting in the nerve fibers closer to the effector organs to be very short in length
So, the correct option is 'all of the above'

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

Which of the following options correctly identifies the effect of sympathetic and parasympathetic neural system on given features or organs?

  1. Feature/organ - Salivary glandsSympathetic neural system - Stimulates secretionParasympathetic neural system - Inhibits secretion

  2. Feature/organ - Pupil of the eyeSympathetic neural system - DilatesParasympathetic neural system - Constricts

  3. Feature/organ - Heart rateSympathetic neural system - DecreasesParasympathetic neural system - Increases

  4. Feature/organ - Intestinal PeristalsisSympathetic neural system - StimulatesParasympathetic neural system - Inhibits
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The correct matches are;

1. Feature/organ - Salivary glands
Sympathetic neural system - Inhibits secretion
Parasympathetic neural system - Stimulates secretion

2. Feature/organ - Pupil of the eye
Sympathetic neural system - Dilates
Parasympathetic neural system - Constricts

3. Feature/organ - Heart rate
Sympathetic neural system - Increases
Parasympathetic neural system - Decreases

4. Feature/organ - Intestinal Peristalsis
Sympathetic neural system - Inhibits
Parasympathetic neural system - Stimulates

So the correct option is 'B'.
Multiple choice biology control and co-ordination in plants and animals nervous system in animals structure of neuron structure and function of neuron

Structure and functional unit of nervous system is

  1. Nephron

  2. Cyton

  3. Neuron

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

Neurons are the structural and functional unit of the nervous system. Each neuron consists of dendrites, axon, and soma. Dendrites are the small extension of nerve cells that receive signals from sensory receptors or other neurons. The long extension of the cell body of the nerve cell is called as axon that serves to conduct the nerve impulse away from the cell body. Cyton /soma is the metabolic center of the nerve cell where the metabolic contents are manufactured. It is not involved in nerve impulse conduction. A nephron is the anatomical and functional unit of kidney and thus is the part of the excretory system. Thus, the correct answer is option C.

Multiple choice biology structure and functions of living organisms -ii nervous system in animals structure of neuron structure and function of neuron role of receptors in the mouth types of teeth circulatory system and organs

The nervous system is formed of 

  1. Brain

  2. Spinal cord

  3. Nerves

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The nervous system is a collection of cells, tissues, and organs ( brain, spinal cord, nerves ) through which an organism receives information from its surroundings and then directs the organism to respond to the stimulus.

So, the correct answer is 'All of the above'.

Multiple choice biology sensations and responses nervous system in animals structure of neuron structure and function of neuron

Which of the following is the part of a neuron?

  1. Axon

  2. Cell body

  3. Dendrite

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The primary components of the neuron are the soma (cell body), the axon (a long slender projection that conducts electrical impulses away from the cell body), dendrites (tree-like structures that receive messages from other neurons), and synapses (specialized junctions between neurons).

Therefore, the correct answer is option D.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

The bulbous structure present at the terminal end of an axon is_______________

  1. Synaptic vesicle

  2. Synaptic knob

  3. Dendrites

  4. Schwann cell
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A. Synaptic vesicle store various neurotransmitters that are released at the synapse.

B. Synaptic knob-The bulbous structure present at the terminal end of an axon.

c. Dendrites-also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project.

D. Schwann cell -also called neurilemma cell, any of the cells in the peripheral nervous system that produce the myelin sheath around neuronal axons.

So, the correct option is 'Synaptic Knob'.

Multiple choice biology plant and animal tissues nervous system in animals structure of neuron structure and function of neuron

Name the part of the neuron, where information is acquired.

  1. Axon

  2. Dendrites

  3. Synapse

  4. Schwann cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Neuron is a structural and functional unit of neural system. It is composed of three major parts- cell body, dendrites and axon.
A. Axon is a long fibre which arises from the cell body and terminates as a bulb-like structure called the synaptic knob which participate in synapse. Hence, the axons take away the information from the cell body of the neuron to which they belong.
B. Dendrites are the short fibers which arise out from the cell body. The dendrites of one neuron receive the electrical impulses from different sources and then transmit these impulses towards the cell body of the neuron to which they belong. Hence, the information is acquired here.
C. Synapse is the nerve impulse which is transmitted from one neuron to another through the junctions. It is formed by the membranes of the pre-synaptic neuron and a post-synaptic neuron.
D. Schwann cells are enclosed in myelin sheath and are lipid rich cells.
So, the correct option is 'Dendrites'.