Tag: zoology

Questions Related to zoology

Destruction of the anterior horn cells of the spinal cord would result in loss of?

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Integrating impulses

  2. Sensory impulses

  3. Voluntary motor impulses

  4. Commissural impulses

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Correct Option: C
Explanation:
Destruction of the anterior horn cells of the spinal cord would result in loss of voluntary motor impulses. It is because the anterior horn cells (also called anterior grey column), which is the front column of grey matter in the spinal cord contains motor neurons that affect the axial muscles.
So, the correct option is 'Voluntary motor impulses'. 

Ventral root of spinal nerve has 

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Sensory fibres

  2. Motor fibres

  3. Both of the above

  4. None of the above

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Correct Option: B
Explanation:

The ventral root (motor root) of each spinal nerve consists of axons from motor neurons, whose cell bodies are found within the grey matter of the spinal cord. A ventral root and a dorsal root unite to form a spinal nerve, which passes outward from the vertebral canal through an intervertebral foramen.

Meninges are the membranes of connective tissue. What is the location of these membranes in the human body?

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Brain and spinal cord

  2. Cerebrum

  3. Mid brain

  4. Spinal cord

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Correct Option: A
Explanation:
The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system. Infection of the meninges is called Meningitis. It could be bacterial, Viral, Fungal or Protozoal in origin.

The "butterfly " like structure surrounding the central region of human's spinal cord is called as

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Funiculus

  2. Horn

  3. White matter

  4. Grey matter

Show answer
Correct Option: D
Explanation:

The grey matter, in the center of the spinal cord, is shaped like a butterfly and consists of cell bodies of interneurons and motor neurons, as well as neuroglia cells and unmyelinated axons. Projections of the grey matter (wings) are called as horns. Together, the grey horns and the grey commissure form the "grey H."

The dorsal root of spinal cord contains

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Somatic motor fibres

  2. Visceral motor fibres

  3. Somatic sensory fibres

  4. Visceral sensory fibres

Show answer
Correct Option: C
Explanation:

A posterior root ganglion (spinal ganglion) (also known as a dorsal root ganglion), is a cluster of nerve cell bodies (a ganglion) in a posterior root of a spinal nerve. The axons of posterior root ganglion neurons are known as afferents. The posterior root ganglia lie along the vertebral column by the spine. The nerve endings of posterior root ganglion neurons have a variety of sensory receptors that are activated by mechanical, thermal, chemical, and noxious stimuli.

Thus, dorsal root ganglia contain cell bodies of sensory neurons. Axons of these sensory neurons travel into the spinal cord via the dorsal roots.
Thus, the correct answer is option C.

What is found in the periphery of spinal cord?

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Grey matter

  2. Myelinated nerve

  3. White matter

  4. Notochord

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Correct Option: C
Explanation:

In cross-section, the peripheral region of the cord contains neuronal white matter tracts containing sensory and motor neurons. Internal to this peripheral region is the grey matter.

Axons of preganglionic neurons in the human sympathetic nervous system emerge from which of the following regions of the spinal cord?

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. Cranial and sacral

  2. Thoracic and lumbar

  3. Cranial and thoracic

  4. Lumbar and sacral

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Correct Option: B

Cell bodies of neurons bringing afferent information into the spinal cord are located in

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. dorsal root ganglia

  2. ventral root ganglia

  3. gray matter of the spinal cord

  4. white matter of the spinal cord

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Correct Option: A

If dorsal root of spinal cord is broken down then its effect is 

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. No effect on impulse

  2. Impulse is transmitted fast

  3. Impulse is transmitted but slowly

  4. No impulse is transmitted from receptor

Show answer
Correct Option: D
Explanation:

The dorsal root or the posterior root is the main bundle of nerve fibers that branch off from the spinal cord to enter other areas of the body. This combines with the ventral root to form the spinal nerve. and becomes the afferent sensory root and is responsible for carrying and transmitting the sensory information from the body to the brain for processing the signals by the brain. If the dorsal root is broken, then the transfer of information will not be possible. Thus, the correct answer is option D.

The location of filum terminale is

zoology neural control and coordination structure and function of spinal cord the spinal cord spinal cord

  1. In the skull

  2. In the thorax

  3. In the lumbar vertebrae

  4. In the pelvic girdle

Show answer
Correct Option: C
Explanation:

The spinal cord is the extension of the medulla oblongata that runs down through the foremen of magnum. The lowest part of the spinal cord is narrow and it is called the conus medullaris. The conus medullaris is present at the L$ _{1}$ vertebrae. The terminal part of the conus medullaris is a thread-like structure that is made up of fibrous connective tissue called the filum terminale. It is the non-nervous part of the spinal cord that can be seen in the lumbar vertebrae.

Hence, the correct answer is 'In the lumbar vertebrae'