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

Which of the following statements is incorrect?

  1. Medulla secretes certain neurotransmitters.

  2. Adrenal medulla is a part of the nervous system.

  3. The medullary hormone bind to adregenic receptors.

  4. Adrenalin is known as tonus hormone.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Adrenalin is known as emergency hormone. Noradrenaline is the tonus hormone for the circulatory system.

Multiple choice

Clostridium tetani produces a potent toxin which causes constant constriction of muscles. Which of the following cells of the nervous system are targeted by this toxin?

  1. Pyramidal cells

  2. Renshaw cells

  3. Purkinje cells

  4. Basket cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Renshaw cells are targetted by the toxin of Clostridium tetani. When wounds are contaminated with Clostridium tetani, the toxin travels to the spinal cord where it inhibits the release of glycine, an inhibitory neurotransmitter, from Renshaw cells. As a result, alpha motor neurons become hyperactive and muscles constantly contract.

Multiple choice

Myelin sheath provides insulation to the axon that allows electrical signals to propagate more efficiently. Which of the following cells produce myelin sheath in neurons of CNS?

  1. Astrocytes

  2. Oligodendrocytes

  3. Schwann cells

  4. Enteric glial cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Oligodendrocytes are the glial cells that coat axons in the central nervous system (CNS) with their cell membrane, forming a specialised membrane differentiation called myelin, to produce the so-called myelin sheath. Myelin sheath provides insulation to neuron and allows electrical signals to propagate more efficiently.

Multiple choice

Which of the following statements is false?

  1. Slit sense organs enable spiders to detect ground vibrations produced by approaching prey.

  2. Among arthropods, the greatest visual acuity is found in the predaceous mantis shrimp.

  3. The sensory nerve endings are lodged in cuticular hair.

  4. The arthropod nervous system consists of a dorsal brain and a ventral, ganglionated longitudinal nerve cord.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is false. Slit sense organs enable spiders to detect web vibrations produced by trapped insects and they permit scorpions to detect ground vibrations produced by approaching prey.