Biology

Nervous System and Neurons

1,224 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

Spinal Cord

  1. Epithelial

  2. Connective

  3. Muscular

  4. Nervous
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The spinal cord is a major component of the central nervous system, which is composed primarily of nervous tissue.

Multiple choice

Nerves

  1. Epithelial

  2. Connective

  3. Muscular

  4. Nervous
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nerves are bundles of fibers that transmit impulses of sensation to the brain or spinal cord, and impulses from these to the muscles and organs; they are nervous tissue.

Multiple choice

Which structures are part of a neuron? (Select all that apply.)

  1. Axon

  2. Opioid

  3. Cortex

  4. Dendrite
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation

Neurons are the fundamental units of the nervous system, consisting of a cell body, dendrites, and an axon. Opioids are chemicals that interact with neurons, and the cortex is a structure made of many neurons, not a part of a single neuron.

Multiple choice biology coordination - the linking system nervous systems involved in emotions types of nervous system components of nervous system

The electrical potential difference between outside and inside of a nerve axon before excitation is known as ____________.

  1. Resting potential

  2. Action potential

  3. Spike potential

  4. Reaction potential
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The electrical potential difference between outside and inside of a nerve fibre before excitation (polarized nerve fibre) is known as resting potential whose value is $-70$ mV.

Multiple choice zoology control and co-ordination in plants and animals the reflex action reflex action and reflex arc basic reflex action and reflex arc

A reflex arc does not involve

  1. A receptor

  2. A sensory pathway

  3. A motor pathway

  4. The brain
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A reflex arc is a simple nervous pathway and consists of the sensory receptor, afferent neuron, center, efferent neuron and effector organ. 

The afferent/sensory neurons transmit the sensory information from sensory receptors to the spinal cord (sensory pathway). The interneurons of spinal cord integrate the incoming information and signal is relayed to motor/efferent neurons.  
The motor pathway transmits the signal from motor neurons to the effector organs (muscles and glands etc). Thus, reflex arc transmits the information from receptor to effector via the spinal cord. The brain is not the part of the reflex arc. 

Multiple choice zoology control and co-ordination in plants and animals the reflex action reflex action and reflex arc basic reflex action and reflex arc

Spinal reflex is located in the ________

  1. Nerves

  2. Brain

  3. Epithelial lining

  4. Spinal cord
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • Spinal reflex or withdrawal reflex protects the body from the damaging stimulus. 
  • It is located in the spinal cord. In this reflex pathway, more than one relay neuron connects the sensory and motor neuron.

Therefore, the correct answer is option D.

Multiple choice zoology control and co-ordination in plants and animals the reflex action reflex action and reflex arc basic reflex action and reflex arc

Reflex arc is a neural pathway that involves .......... nervous system. 

  1. Peripheral

  2. Autonomous

  3. Central

  4. Both A and C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • Reflex arc involves both peripheral and central nervous systems. As the route followed by nerve impulses in the production of a reflex act, is from the peripheral receptor organ, through the afferent nerve, to the central nervous system synapse, and then through the efferent nerve, to the effector organ. 

Therefore, the correct answer is option D.

Multiple choice biology transport in mammals regulation of the activity of heart drug, tobacco and alcohol consumption community health and hygiene

An Evoked Potential Studies (EPS) enables us to

  1. Evaluate different sensory functions

  2. Detect clinically silent tensions

  3. Study hearing and vision in children

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

Evoked potential studies measure electrical activity in the brain in response to stimulation of sight, sound, or touch. Stimuli delivered to the brain through each of these senses evoke minute electrical signals. These signals travel along the nerves and through the spinal cord to specific regions of the brain and are picked up by electrodes, amplified, and displayed for a doctor to interpret. Evoked potentials studies involve three major tests that measure response to visual, auditory, and electrical stimuli. Evoked potential studies may be used to assess hearing or sight, especially in infants and children, to diagnose disorders of the optic nerve, and to detect tumors or other problems affecting the brain and spinal cord. The tests may also be performed to assess brain function during a coma.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

The core component of central nervous system is 

  1. Blood

  2. Neurons

  3. Ganglia

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Neurons are the basic units of the nervous system. Every neuron is made of a cell body (also called a soma), dendrites and an axon. Dendrites and axons are nerve fibres.
  • The central nervous system consists of the brain and the spinal cord
  • The human brain contains around 100 billion neurons.
  • Hence the core component of the central nervous system is  Neuron.
  • So, the correct answer is 'Neurons'.
Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

A minute gap across which impulse pass by neurotransmitter is called as a 

  1. Cleft

  2. Synapse

  3. Nerve impulse

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

The gap between two neurons across which impulses are conducted is known as a synapse. Synapse is a structure that permits a neuron to pass an electrical or chemical signal to another cell. It is important for neuronal function. 
Thus, the correct answer is option B.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Area of coming together of two neuron ends or between a dendron and axon ends is?

  1. Junction

  2. Synapsis

  3. Synapses

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

  • In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. 
  • Synapses are stabilized in position by synaptic adhesion molecules (SAMs) projecting from both the pre- and post-synaptic neuron and sticking together where they overlap. Hence. Area of coming together of two neuron ends or between a dendron and axon ends is synapses.
So, the correct answer is 'synapses'.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

A small gap that helps neurotransmitter to pass nerve impulse is called as

  1. Neuron

  2. Synapse

  3. Ganglia

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

The gap between two neurons across which impulses are conducted is known as a synapse. The presynaptic is the region of the axonic end of one neuron and the post synaptic is the dendritic end of the other neuron. It is a structure that permits a neuron to pass an electrical or chemical signal to another cell and acts as a communication point between the neuron and the target organ. The nerve impulses are transmitted and received with the help of this regions. 
Thus, the correct answer is option A.