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

Auditory nerve is formed by

  1. vestibular and trochlear nerve

  2. cochlear nerve

  3. trochlear and cochlear nerve

  4. vestibular and cochlear nerve
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because auditory nerve is formed by the union of vestibular nerve and the cochlear nerve.

Multiple choice

Unipolar neurons are present in

  1. dorsal root ganglia of spinal cord

  2. retina of eye

  3. olfactory epithelium

  4. grey matter of brain
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the region where unipolar neurons are present.

Multiple choice

Which of the following is true about the myelinated nerve fibres?

  1. They appear grey in colour.

  2. They occur in autonomic nerves.

  3. They give off collateral nerve fibres.

  4. They carry nerve impulse slowly.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is true about myelinated nerve fibres whereas collateral nerve fibres are absent in non myelinated fibres.

Multiple choice

The taste receptor molecules are found on the top of the microvilli of the taste cells. Which of the following tastes opens voltage-regulated Ca2+ gates, which ultimately helps in releasing the concern neurotransmitter?

  1. Umami

  2. Sweet

  3. Bitter

  4. Sour

  5. Salt
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

The simplest receptor found in the mouth is the salt (NaCl) receptor. An ion channel in the taste cell wall allows Na+ ions to enter the cell. This on its own depolarises the cell, and opens voltage-regulated Ca2+ gates, flooding the cell with ions and leading to neurotransmitter release.

Multiple choice

The fifth cranial nerve of a frog is called

  1. trigeminal

  2. opthalmic

  3. vagus

  4. optic

  5. -
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The trigeminal nerve is the largest and most complex of the twelve cranial nerves. It is the motor nerve for the muscles of mastication. It is the fifth cranial nerve.

Multiple choice

The transmission of nerve impulse is unidirectional because

  1. the nerve fibre is insulated by medullary sheath

  2. the sodium pump starts from cyton and proceeds towards axonal ends

  3. the neurotransmitter is released only at dendrite ends

  4. the neurotransmitter is released only at the axonal ends
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The transmission of nerve impulse is unidirectional because the neurotransmitter is released only at the axonal ends.