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 biology animal tissue types of neuron nervous tissue neural tissues

Most of the neurons of our body are

  1. Unipolar

  2. Bipolar

  3. Pseudounipolar

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

A unipolar neuron is a type of neuron, in which only one neurite or protoplasmic process extends from the cell body. Bipolar neuron is a type of neuron, which has two processes extending from the cell body. Pseudounipolar contains an axon, that has split into two branches, one branch runs to the periphery and the other to the spinal cord. A multipolar neuron is a type of neuron that possesses a single, long axon and many dendrites. The majority of the neurons are multipolar.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Show the pathway of electric impulse.

  1. $Dendrite \rightarrow Cell\ body\rightarrow Axon\rightarrow$ to its end
  2. $Cell\ body \rightarrow Dendrite\rightarrow Axon\rightarrow$ to its end
  3. $Axon\rightarrow Cell\ body\rightarrow Dendrite\rightarrow$ to its end
  4. $Dendrite\rightarrow Axon\rightarrow Cell\ body\rightarrow$ to its end
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The dendrites are the short, cytoplasmic extension which is present in the sensory organs and are responsible for the reception of the electric impulse. The dendrite passes the electric impulse to the cell body which passes the impulse to the axon. The axon is the long cytoplasmic extension of the neuron. There are telodendrons which are present at the tail of the axons. These regions can release neurotransmitters which can help in the transmission of the impulse through the synapse to the next neuron.

Thus, the correct answer is option A. 

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Afferent nerve fibres carry impulses from 

  1. Effector organs to central nervous system

  2. Receptors to central nervous system

  3. Central nervous system to muscles

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

In the nervous system, afferent neurons (otherwise known as sensory neurons), carry nerve impulses from receptors or sense organs toward the central nervous system.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Which is not part of nervous tissue?

  1. Cyton

  2. Axon

  3. Myelin

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

Cyton, axon, and myelin are all components of a neuron. Intermedin is a hormone produced by the intermediate lobe of the pituitary gland, not a part of nervous tissue.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Multipolar neuron means.

  1. With one dendron and one axon

  2. With many dendrons and one axon

  3. With one dendron and no axons

  4. With many dendrons and no axons
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The multipolar neuron is the neuron which has many dendrons and one axon.
  • Multipolar neurons are the most common type of neuron. They are located in the central nervous system (brain and spinal cord) and in autonomic ganglia.
  • Hence Multipolar neuron means The neurons which have many dendrons and one axon.
  • So, the correct answer is 'with many dendrons and one axon'.
Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Direction of nerve impulse is reversed in nerve with.

  1. Axo-axonic

  2. Axo-dendritic

  3. Both A and B

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

Answer is option A i.e. "Axo-axonic"
Axo-axonic is a type of neural structure synapse between two axons. In case case, the axon of one neuron makes synapse with axon of the other neuron (i.e both, site of neurotransmitter release and site of receptor binding, are axons). It is essential for the transmission of nerve impulses. Axoaxonic junction modulate neuronal transmission by either inhibiting or facilitating depolarization at the presynaptic membrane.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Cells of the nervous system that are specialized to provide support arid protection are known as

  1. Schwann cells

  2. Axons

  3. Neurons

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

Neurons feature many thin projecting fibres called axons, which penetrate deep into tissues. They are able to communicate with other cells by chemical or electrical means at synapses. Neuronal function is supported by neuroglia, specialized cells which provide nutrition, mechanical support, and protection.

So, the correct option is 'Neuroglia'.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Most of the human neurons are

  1. Multipolar

  2. Bipolar

  3. Unipolar

  4. Pseudo-unipolar
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

a) Multipolar neurons have more than two processes emanating from the neuron cell body. They are mainly located in central nervous system and are most common type of human neurons.

b) Bipolar neurons are relatively rare. They are sensory neurons found in olfactory epithelium, the retina of the eye, and ganglia of the vestibulocochlear nerve.
c) A unipolar neuron is a type of neuron in which only one protoplasmic process (neurite) extends from the cell body. 
d) Pseudounipolar neurons have an axon that is split into two different branches, one running into the periphery while the other running into the spinal cord. It is different from a conventional unipolar neuron because it lacks a separate dendritic process
So, the correct answer is 'Multipolar'

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Unipolar nerve cell means _______________.

  1. Nerve cell with one dendron

  2. Nerve cell with many dendrons

  3. Nerve cell without dendron

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Unipolar nerve cell means Nerve cell without dendron. They have only one structure extending from the soma(cell body).
  • Unipolar neurons are common in insects, where the cell body is often located at the periphery of the brain and is electrically inactive.
  • Hence Unipolar nerve cell means Nerve cell without dendron.
  • So, the correct answer is 'Nerve cell without dendron'.
Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Which system transmits impulses between different parts of the body?

  1. Musculoskeletal system

  2. Endocrine system

  3. Circulatory System

  4. Nervous system

  5. Reproductive system
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A complex network of nerve cells or neurons forms the nervous system. This system is responsible for transmitting electrical impulses throughout the body.

So, the correct answer is 'Nervous system'.

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

The nerves that carry the messages towards the CNS from sense organs are __________.

  1. Afferent neurons

  2. Efferent neurons

  3. Interneurons

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Neurons that receive information from our sensory organs (e,g. eye, skin) and transmit this input to the central nervous system (CNS) are called afferent neurons.
B. Neurons that send impulses from the CNS to our limbs and organs are called efferent neurons.
C. Interneurons create neural circuits, enabling communication between sensory or motor neurons and the CNS.
So, the correct answer is 'Afferent neurons'.
Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Neural proteins are mainly synthesized in__________

  1. Cell body of neuron

  2. Axon

  3. Dendrites

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

  • The human body is made up of trillions of cells. Cells of the nervous system called nerve cells or neurons, are specialized to carry "messages" through an electrochemical process. Neurons carry out basic cellular processes such as protein synthesis and energy production.
  • Protein synthesis in the extensions of nerve cells, called dendrites, Local protein synthesis in dendrites, not in the cell body of nerves, provides the ability to respond rapidly and selectively to external stimuli. 

So the answer is 'Dendrites'. 

Multiple choice biology animal tissue types of neuron nervous tissue neural tissues

Largest number of cell bodies of neuron in our body are found in the_________.

  1. Retina

  2. Spinal cord

  3. Brain

  4. Tongue
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The largest number of cell bodies of neurons in our body is found in the brain.
The human brain is the main organ of the human nervous system. It is located in the head, protected by the skull. It has the same general structure as the brains of other mammals, but with a more developed cerebral cortex.
The human brain is composed of neurons, glial cells, and blood vessels.