Tag: structure and function of neuron

Questions Related to structure and function of neuron

The area where medullary sheath is absent in the nerve fibre is

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

  1. Nissl granules

  2. Schwann cells

  3. Node of Ranvier

  4. Schwann node

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Correct Option: C
Explanation:

The medullary sheath is composed of a shinning, white, fatty substance called myelin. This sheath perhaps serves as an insulating layer, preventing loss of energy of the nerve impulse during its passage along the fibre. The medullary sheath is continuous around the fibres in the central nervous system, but in the fibres of the peripheral nerves, it is absent at certain points known as the Node of Ranvier. The part of a nerve fibre between two successive nodes is termed the internode.

So, the correct answer is 'Node of Ranvier'.

Choose the odd pair.

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

  1. Areolar connective tissue - Collagen

  2. Epithelium - Keratin

  3. Muscle fibre - Actin

  4. Neuron - Melanin

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Correct Option: D

Non-excitable variously shaped cells found between neurons are ________________.

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

  1. Glial cells

  2. Schwann cells

  3. Dendrites

  4. Nissl bodies

Show answer
Correct Option: A
Explanation:

Answer is option A i.e. "Glial cells"
Glial cells- These cells are the helper cells in the central nervous system. They surround the neurons and provide insulation between two neurons. There are variously shaped like oligodendrocytes, astrocytes (star-shaped), ependymal etc.
Dendrites- They are branched extensions of nerve cells.
Nissl bodies- It is a large granular body found in the neuron cells.
Schwann cell- They are present in the axon of a neuron. They help in supporting nerve regeneration.
Thus the correct answer is "Glial cells"

On nerve fibres, to prevent leakage of an impulse, a layer of ...... is found.

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

  1. Rod cells

  2. Neurilemma

  3. Axons

  4. Myelin sheath

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Correct Option: D
Explanation:

Myelin is an insulating layer, or sheath, that forms around nerves. It is made up of protein and fatty substances. The fat helps to insulate the axons from electrically charged atoms and molecules. The purpose of the myelin sheath is to allow electrical impulses to transmit quickly and efficiently along the nerve cells.

Some cell in our body can be over a feet long. They are

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

  1. Muscle cells

  2. Bone cells

  3. Nerve cells

  4. Gland cells

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Correct Option: C
Explanation:

Certain neurons or nerve cells may almost equal the length of body itself. The axon of a motor neuron in the spinal cord, that innervates a muscle in the foot can be about 1 meter (3 feet) in length.

Which one is absent in neurons ?

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

  1. Neurilemma

  2. Axon

  3. Sareolemma

  4. Dendrites

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Correct Option: C

The charge on the outer side of neuron is

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

  1. +ve

  2. -ve

  3. Zero

  4. Alternate -ve and +ve

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Correct Option: A

In axon of a neuron, the impulse is generated by exchange of

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

  1. Sodium and chlorine

  2. Magnesium and chlorine

  3. Calcium and potassium

  4. Sodium and potassium

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Correct Option: D

Touch on the right side stimulate neurons on

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

  1. Right somatic sensory area

  2. Right somatic motor area

  3. Left somatic sensory area

  4. Both B and C

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Correct Option: C

Myelin sheath is derived from

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

  1. Neuroglial cells

  2. Schwann cells

  3. Nerve cells

  4. All of these

Show answer
Correct Option: B
Explanation:

  • Myelin sheath is formed by oligodendrocytes in the CNS and by Schwann cells in the peripheral nervous system. 
  • These cells wrap layer upon layer of their own plasma membrane in a tight spiral around axon. 
  • The insulating layer checks the leakage of charge and lesser stoppage points (nodes of Ranvier) leading to acceleration of the conduction and conservation of the metabolic energy.
So, the correct option is 'Schwann cells'.